The large-cup (“jumbo” or “max capacity”) forceps requires a large channel, a so-called therapeutic endoscope (biopsy channel 3.6 to 3.7 mm). Some newer designs are intended to provide larger biopsy specimens with the conventional 2.8-mm channels and intermediate-sized channels such as pediatric colonoscopes.¹ Larger capacity biopsy forceps are highly desirable to optimize the diagnostic yield. Part of the reason that only a few endoscopists have used the large-cup forceps is the reluctance to use larger capacity forceps that require the larger channel. There is also a puzzling antipathy toward the use of a larger forceps that obtains superior sized specimens. Studies have been done to show that a larger forceps is unnecessary, as if the larger forceps represented a serious threat or a “ploy.”²

Larger capacity forceps biopsies yield two to three times the surface area but are not generally much deeper (Fig. 5.1).The main objective with biopsy is not to obtain more representative sampling of a whole organ but to enable the histotechnologist to see the biopsy specimens to orient them (see Fig. 5.1). Histotechnologists cannot orient small to tiny specimens. The resultant sections with larger capacity forceps are infinitely superior. Proper orientation during paraffin embedding is impossible with often delivered “fleabite”-sized specimens as part of a group of biopsies in a tissue block.

Fig. 5.1 The advantage of a larger capacity forceps is not to sample more terrain (e.g., in surveillance in Barrett’s esophagus and ulcerative colitis) but to provide larger sized biopsy specimens so that the histotechnologist can orient the specimens for embedding, on edge. That is more difficult with small specimens. With tiny biopsy specimens, it is impossible.

Orientation for embedding in paraffin is the key to maximizing the diagnostic yield from mucosal biopsies. Orientation with crypts and villi are lined up and not cross cut like a stack of doughnuts. This orientation permits assessment of the amount of lamina propria inflammation, focal lesions such as granulomas, and intraepithelial lymphocytes (especially small bowel). In the colon, oriented sections permit assessment of crypt branching (architectural distortion) for differential diagnosis regarding chronicity and assessment of lesser grades of dysplasia by being able to use crypt architectural disorganization as opposed to only cytologic change in cross-cut sections. Oriented sections are required to maximize the yield for focal lesions.

Biopsy specimens taken with larger capacity forceps usually contain very little submucosa or none at all. It is sometimes difficult to obtain specimens with sufficient submucosa when the objective is to diagnose amyloid or rule out or hunt for vasculitis in submucosal blood vessels.

Multiple Biopsy Specimen Forceps

Multibite forceps are designed to obtain multiple specimens with a single pass. They may be judged as adequate by some pathologists, but for what purposes? Biopsy specimens are generally tiny and pale compared with the quality of specimens of other forceps biopsies. The aggregate tissue is considered one advantage, but that does not guarantee any higher yield when the aggregate nets multiple tiny cross-cut sections.

Hot Biopsy Forceps

Hot biopsy forceps are insulated pinch biopsy forceps through which coagulation current is passed. They have been used for removal of diminutive colonic polyps, especially tiny ones in the rectum. They are not commonly used.

Cold Snare Biopsy

Cold snare biopsy is advocated instead of hot biopsy to remove diminutive polyps from the colon and submit them all to the pathology laboratory.³ A larger capacity biopsy forceps is just as effective for small polyps. In the absence of a cold snare, cold forceps is still preferable to hot biopsy.³ Fundic gland polyps have a characteristic appearance and location, and cold snare or any kind of snare is not generally required. However, in the case of larger fundic gland polyps, especially in the setting of familial polyposis, removing some may be done to rule out dysplastic change in them. The polyps almost always come off easily without bleeding. If the endoscopist is uncertain that a polyp is fundic gland type, a cautery forceps should be used. The endoscopist should always be prepared to apply a hemostasis technique if bleeding is excessive after a cold snare biopsy. Cold snare biopsy of gastric polyps less than 7 mm to distinguish hyperplastic from adenomatous polyps is useful in the appropriate clinical circumstances.

Suction Biopsy

Suction biopsies are rarely performed.

Grasp Biopsy

Grasp biopsies are performed through a rigid sigmoidoscope using an alligator cutting forceps. These biopsies are rarely performed in clinical gastroenterology practice, but they may be useful for indurated distal rectal tumors that are difficult to grasp with endoscopic biopsy forceps.

Laparoscopic Biopsy

Laparoscopic full-thickness gut biopsies are useful when diagnosis and type classification of intestinal pseudoobstruction is required.^4,⁵

Improving the Quality of Forceps Pinch Biopsy Specimens

Double Bites

The term double bites refers to taking two specimens with a single pass of the biopsy forceps. With conventional-sized forceps, this double-bite technique often yields a tiny second biopsy specimen, or a “macrocytology” (Fig. 5.2). However, the double-bite technique may be used successfully in the colon in ulcerative colitis biopsy surveillance and in the small bowel using a larger capacity forceps. In the esophagus, the double-bite technique is difficult because of the need for angulation and risk of loss of the first biopsy specimen obtained. In the stomach, the size of the specimens is often so generous with the first pass that there is scant room for a second biopsy.

Fig. 5.2 Double-bite inadequate-sized biopsy specimens in Barrett’s esophagus. A, Specimen at the lower left is the only one that can be oriented, and it is superficial. The others are scrapings. B, One of the fragments (inset in A enlarged) shows high-grade dysplasia.

To perform this technique, after the first biopsy specimen is obtained, the closed forceps is placed with slight pressure on the wall where the next specimen is to be taken and is opened against a bit of wall pressure. This pressure helps prevent the first specimen from falling out into the lumen. After opening the forceps poised to biopsy, a few staccato bursts of suction are applied, and then the forceps is closed quickly to obtain the second specimen. One does not always obtain two biopsy specimens. I usually obtain two specimens about once in three to five times.

Turn-in Technique

In areas where one has to perform a biopsy at an oblique angle, as in the esophagus or for gritty lesions, it helps enormously to use the turn-in technique. The opened forceps is first drawn back flush with the endoscope tip. The tip of the endoscope is then deflected 90 degrees against the wall, allowing the forceps to be advanced en face by moving the endoscope in, rather than extending the forceps. It is advanced until resistance is met, then suction is applied briefly, and the forceps is closed. It is not necessary to see what is being biopsied if any targeted areas were cleared with biopsies as in Barrett’s esophagus surveillance. In the case of a focal lesion, the endoscope is positioned right over the lesion and turned into it using the large up-down hand control knob on the endoscope. For endoscopists who want experience with the turn-in technique, the best way to obtain it is to try it in more spacious areas, such as the stomach, in the course of performing gastric biopsies.

6 O’clock Position and Biopsies of Gastroesophageal Junction (Cardia) Lesions

When areas are difficult to get at, rotation of the endoscope to the 6 o’clock position makes it infinitely easier to obtain biopsy specimens and to target more accurately (Fig. 5.3). This position is especially invaluable in biopsy surveillance of Barrett’s esophagus where the 12 o’clock position tends to be ignored for visualization and biopsy targeting. The endoscope is rotated so that what was at 12 o’clock is now at 6 o’clock.

Fig. 5.3 Value of viewing cardia lesions on retroflexion from the gastric side and positioning at 6 o’clock. A, End-on view of eccentric Z line. B, Retroflexion view in the stomach. Eccentric part is positioned at 6 o’clock. Biopsy, if indicated, is easier from this aspect. C, Small gastroesophageal junction mass as viewed from the stomach on retroflexion and rotated to the 6 o’clock position for biopsy.

For lesions at the gastroesophageal (GE) junction, it is often invaluable to visualize the area on turnaround in the stomach and target biopsy or endoscopic resection from this perspective (see Fig. 5.3C). This maneuver works only if the patient has a hiatal hernia. After the turnaround is done in the stomach, air insufflation is set on high. The endoscope is advanced by slowly withdrawing until the endoscope tip advances right to the GE junction. In this way, there is end-on visualization of a lesion. Additionally, the endoscope can often be torqued slightly to place the lesion in or near the favored 6 o’clock position (see Fig. 5.3). If torque is required for biopsy positioning, the endoscopy assistant maintains it while the biopsy forceps is targeted to the lesion. In the turnaround position from the stomach, some lesions cannot be accessed despite torquing or twisting.

Reducing the Number of Uninterpretable Biopsy Specimens

Independent of which forceps or technique is used, one key way to reduce the uninterpretability rate of biopsy is to have the endoscopy assistant indicate when a biopsy specimen is nearly invisible or when there is only blood or mucus. Such specimens should be discarded. In the process of taking biopsy specimens in our unit, the endoscopy assistant calls out whether a specimen is adequate or otherwise. Apart from size, superficial shallow specimens can be identified by the endoscopy assistant as translucent. Even the most experienced “biopsy veterans” have to go back every five or six biopsies. Unless endoscopists look at the biopsy specimens with the pathologist, they never know how many specimens of a group are interpretable. Histologic diagnoses are sometimes made by piecing together several uninterpretable fragments in the “mind’s eye.”

Minimizing Biopsy Surveillance Antipathy and Biopsy Exhaustion or Boredom

It is likely nearly impossible to reach a state of “joy of biopsy” even when the reason for the endoscopy is tissue-is-the-issue. Examples include surveillance for dysplasia and cancer in ulcerative colitis and Barrett’s esophagus. Part of the antipathy to surveillance biopsies is that the “drudgery effect” is eagerly passed on to fellows from one generation to the next by the endoscopy attending physicians.

When multiple biopsies are required, it helps enormously to have a second assistant in the room to operate the forceps and handle the tissue while the other assistant monitors the patient. For upper endoscopic procedures such as Barrett’s esophagus surveillance, a well-sedated patient who does not keep bolting upright helps. The use of an anticholinergic before the procedure may reduce saliva and gastrointestinal secretions, and is routine in some practices.

Tissue Handling

Transferring Biopsy Specimens from Forceps to Fixative

The best way to remove biopsy specimens from the forceps is to use a blunt probe to push the specimen out from the base of the opened forceps cups. If one pushes the specimen out by pressing it from the top of the opened forceps or picking at it, the specimen becomes squashed.

Shaking biopsy specimens off the forceps into a fixative bottle may traumatize the tissue and cause denudation of the epithelium, especially from the gastric body. Endoscopists who use the shake technique should alert the pathologist to look for detached epithelium in biopsy specimens from different parts of the gastrointestinal (GI) tract and give feedback. Most pathologists are so used to seeing detached epithelium that they assume it is a default feature (norm) from the trauma of the scope or the forceps.

When exudative lesions are biopsied for diagnosis, shaking specimens into the fixative may peel off the exudate that contains the evidence for the presence of organisms, especially Candida and herpes simplex. These organisms reside in the surface exudate or epithelial slough. Cytomegalovirus does not, and it requires biopsy for diagnosis.

Orientation of biopsy specimens on support materials in the endoscopy unit is not required in clinical practice and in inexperienced hands may lead to more tissue trauma. The key to having well-oriented, high-quality biopsy specimens for histologic examination rests with the pathology histotechnologist’s ability and motivation to embed the tissue “on its edge” in paraffin and obtain sections through the central core of the specimens.⁶ That depends on providing the histotechnologist with specimens of adequate size.

Number of Biopsy Specimens in a Fixative Bottle

Most histotechnologists cannot line up more than four biopsy specimens in a tissue block during embedding and section them so that all are represented in optimal orientation for interpretation (Fig. 5.4). Endoscopists claim that they put 10 or more specimens in a single bottle to reduce the costs. They do not usually get feedback, however, and if they did, they would learn that only half or less of those 10 specimens may be fully interpretable (see Fig. 5.4). In one regional community pathology laboratory, the pathologists separate the biopsy specimens themselves for embedding at four or five per cassette.

Fig. 5.4 Too many biopsy specimens placed into one fixative bottle and in one tissue block. Fragments of variable sizes cannot be positioned en bloc, and each biopsy specimen is not oriented. Dark lines represent tissue wrinkling in sectioning. The hallmark of grossly misoriented biopsy specimens is shown at the bottom as cross-sectioned circles (“doughnut effect”) with no clue as to the real architecture.

Polyps: Identifying the Stalk Region

When snare polypectomy is used for the removal of pedunculated or sessile polyps, the key part of the specimen for cancer diagnosis is in the stalk region or the base in the case of sessile polyps (Fig. 5.5). Stalks retract right after removal of the polyp and often shrink further and disappear after fixation. The best way to identify the stalk is to impale it with a short (1-inch) 25-gauge needle, right to the hub with the needle point emerging at the most convex part of the tip of the polyp (see Fig. 5.5). An alternative is to ink the polyp stalk after removal. After fixation for a few hours, the polyp is bisected with a scalpel or razor blade in the pathology laboratory. The two bisected halves are embedded facedown, and this way the first sections to come off are those that show the stalk region in its best orientation.⁶ Larger specimens should go right to the pathology laboratory to be assessed as gross specimens.

Fig. 5.5 Polypectomy, first preinked. The base of the polyp has a needle inserted through to the tip of the polyp. In the laboratory, the polyp is bisected along the needle path, and the central halves of the polyp are embedded facedown so that the base or stalk zone is represented in the first sections to be collected.

Small Polyps

Small polyps may be retrieved into a suction trap; this does not seem to damage the tissue. One key to using a suction trap without getting the polyp stuck in the suction channel is to have the polyp in a pool of liquid before suctioning. If there is no liquid, saline can be instilled first.

Shave Biopsy

Shave biopsy of larger polyps is to be shunned. The diagnosis of cancer or its exclusion requires that the muscularis mucosae and upper submucosa be visualized. If multiple fragments are submitted with no orientation, the pathologist often cannot provide reassurance that invasion is not present. If there is no choice but to submit two or three pieces of the lesion, each should be marked with ink to show the cut side. This marking permits the pathologist to know where the submucosa is located if present in the specimen. The removal of large specimens requires the same principles that surgeons use in resections.

Endoscopic Mucosal Resection and Endoscopic Resection

Endoscopists and the pathologists who handle specimens from endoscopic resection need to recognize that the specimens should be handled as are any resections for cancer or possible cancer. They are not merely larger biopsy specimens.

It is preferable not to remove the lesions in pieces for the reasons discussed previously. The lesions should be oriented in such a way that there is no doubt about how to handle them. Handling these specimens requires a protocol worked out in advance with the pathologists. The best scheme is to deliver the unfixed specimen to the pathology laboratory so that the pathologist examines it grossly and pins it out before placement in fixative. After fixation, the specimen should be cut into strips and each embedded so that the whole specimen is represented in histologic slides.⁷ In this way, the patient and the endoscopist can be reassured that the focal or early lesion was analyzed optimally with respect to maximal invasion.

Brush Cytology

Brush Cytology in the Diagnosis of Infections

Of the three major potential infections of the esophagus, cytomegalovirus, Candida albicans, and herpesvirus, the latter two are characterized by having the organisms in surface exudate and surface epithelial slough. Cytomegalovirus is embedded more deeply and is not commonly detected in smears of exudate. Smears of exudates for cytologic examination for herpesvirus may provide a rapid diagnosis. Exudate from the brush is smeared onto slides and placed in Papanicolaou fixative. The brushings may also be used for viral culture for herpesvirus, if desired. For this viral culture, a second brushing is swirled around in a culture medium, or the brush tip is cut off with wire cutters and left in the bottom of the culture medium container. For Candida, in our unit, we cut off the brush tip into a tube with several milliliters of the transport liquid and send for examination for hyphae and pseudohyphae.

One person in the unit should periodically check with the microbiologists to see whether they want to change any transport conditions. With most esophageal infections, it is unnecessary to obtain culture verification. Aspirates of duodenal fluid have been used in the past for the diagnosis of Giardia lamblia, but biopsy specimens are at least as sensitive to make the diagnosis.

Brush Cytology for Cancer or Dysplasia Diagnosis

Brush cytology is sometimes the only immediate diagnostic modality available in potentially malignant strictures with marked luminal compromise. One should exercise caution in passing the cytology brush into the lumen of a strictured area to do brushings. Cytologic examinations outside of the setting of endoscopic ultrasound are no longer performed except in the diagnosis of infections (discussed previously). The diagnosis of anal dysplasia, especially in high-risk patients such as patients with human immunodeficiency virus, can be difficult, and anal cytology may be shown to play a diagnostic role in future studies. At the present time, its utility is unknown.

Endoscopist-Pathologist and Pathologist-Endoscopist Communication to Optimize the Diagnostic Yield for Patient Care

A more detailed discussion of the pathologist-endoscopist interaction is available.⁸ Dialogue and communication with pathologists and vice versa are a weak and dysfunctional link, virtually unchanged since the advent of flexible endoscopes.⁸ The potential consequences of this dysfunctional relationship are described subsequently.

False-Positive Diagnoses

False-positive diagnoses may have grave worry consequences for the patients. Three examples follow.

Crohn’s Disease

The main question may be to rule out Crohn’s disease. That question may virtually seal the diagnosis because almost every mucosal abnormality may be compatible with Crohn’s disease. The operative question is rule out focal inflammation or granulomas or both. It is the endoscopist’s responsibility to integrate the answer to this question with the remainder of the work-up. A rush to diagnosis may be premature or erroneous.

Barrett’s Esophagus

The endoscopist asks the pathologist if there is Barrett’s esophagus in an eccentric Z line. An eccentric Z line precludes the diagnosis of Barrett’s esophagus. The first criterion for the diagnosis of Barrett’s esophagus is endoscopic. There is Barrett’s-type mucosa visible in the esophagus above the lower esophageal sphincter (LES). The second criterion is that a biopsy performed above the LES in the esophagus shows intestinal-type goblet cells. An eccentric Z line is not Barrett’s esophagus. Up to 30% of patients with gastroesophageal reflux disease (GERD) and no Barrett’s esophagus have intestinal metaplasia at the Z line.⁹ It is not considered an indication for surveillance. The pathologist may be more circumspect in this example, and instead of calling an eccentric Z line Barrett’s esophagus, the pathologist may call it intestinal metaplasia. The endoscopist may recognize the pathologist’s circumspection and tell the patient he or she has Barrett’s esophagus even if there were no endoscopic criteria for the condition. Commonly, some pathologists compound this in an “enabling” way where no landmarks are given and the biopsy report states “lower esophagus.” The enabling report includes a statement that “if the biopsies were from tubular esophagus then this is Barrett’s esophagus.” This attempt to cover the tracks of the endoscopist results in false-positive diagnoses of Barrett’s esophagus with patients worrying about cancer for life and having regular endoscopy assessments for dysplasia.

Celiac Disease

The endoscopist should not ask: Rule out celiac disease. That will guarantee that any perceived mild abnormality could be “mild celiac disease.” The consequences are predictable: lifelong gluten-free diet, worry, retesting. The operative question should be: Is there any abnormality, Marsh, or otherwise. The endoscopist then makes the differential diagnosis. A Marsh 1 lesion (mild) can be seen in numerous conditions.

What Information Should Be Provided to the Pathologist

Tables 5.1 and 5.2 summarize the information that can be incorporated into a standardized biopsy requisition form. Table 5.1 lists examples of standardized biopsy locations. The endoscopy assistant can prompt the endoscopist if a site given is not “on the list.” Table 5.2 details the other information to be provided to pathologists for them to be able to give more focused diagnoses and differential diagnoses.

Table 5.1 Standardization of Biopsy Locations for Endoscopy Reports and for Pathology Requisition

Esophagus	LES, Z line, and location of biopsy—all as centimeters from incisors. If no Barrett’s esophagus, LES region and Z line are assumed to be at the same location
Stomach	Fundus
	Body, antrum—for each, greater or lesser curvature aspect; proximal, mid, or distal antrum or body
Duodenum and jejunum	Bulb
	Second duodenum
	Beyond second duodenum—estimate only, unless enteroscopy done under fluoroscopy
Ileum	As centimeters from ileocecal valve
Colon	Cecum
	Ascending colon—cecum and ascending colon normally have more inflammatory cells, so separate them from biopsy specimens from other sites
	Hepatic flexure region
	Transverse colon—if multiple sites here, proximal, mid, and distal
	Splenic flexure region
	Descending and sigmoid colon—if colon straight, as centimeters from anorectal margin; if not straight, site descriptions as descending colon, sigmoid, and rectum
	Rectum—as such or if important focal rectal disease, as centimeters or relationship to valves of Houston

LES, Lower esophageal sphincter.

Modified from Weinstein WM: Mucosal biopsy techniques and interaction with the pathologist. Gastrointest Endosc Clin N Am 10:555–572, 2000.

Table 5.2 Information for the Pathologist to Facilitate More Precise and Relevant Diagnosis

Lesion description	If abnormal, use simple language: Thick folds instead of hypertrophic or edematous; thin instead of atrophic
	For description of lesion, give what was seen (e.g., erosions, erythema), rather than an interpretation (e.g., gastritis). Erythema is often equated with esophagitis and gastritis—a poor predictor
	Focal lesion: What does it look like? Biopsy it and the adjacent mucosa within a centimeter, and separate the specimens
Biopsy instrument	Detail type of instrument (e.g., hot biopsy forceps, electrocautery snare) if other than a pinch biopsy forceps
Polyps	Give size and whether sessile or pedunculated, and instrument used (e.g., biopsy forceps, hot biopsy forceps, electrocautery snare)
Key drugs	For all sites: Immunosuppressives, chemotherapy (if recent) or radiotherapy (current, recent, past), NSAIDs
	Stomach: Proton pump inhibitors, dose and duration; recent or current antibiotics or bismuth compounds
	Colon: Type of preparation, local or oral, and type of oral; 5-ASA compounds or other IBD drugs
History	Brief—one or two lines usually suffices
Questions for the pathologist	Be as specific as possible: If biopsy specimens taken from different sites for different questions, indicate the site and the questions associated with it
	What is it? Asking “what is it?” is perfect when the endoscopist does not have any concrete idea

5-ASA, 5-Aminosalicylic acid; IBD, inflammatory bowel disease; NSAIDs, nonsteroidal antiinflammatory drugs.

Modified from Weinstein WM: Mucosal biopsy techniques and interaction with the pathologist. Gastrointest Endosc Clin N Am 10:555–572, 2000.

Endoscopy Report and History

The endoscopy report is often useless in regard to knowing what was seen. This situation coupled with a lack of any relevant clinical information and a question for the pathologist ensures that the pathologist has to perform a blind review of the biopsies. This was discussed previously. The endoscopy report so often tells what the endoscopist believes, not what he or she saw. For example, in an esophagogastroduodenoscopy report, there frequently are two or three diagnoses substituting for what was seen—esophagitis, gastritis, and duodenitis. The history may be brief but relevant. For example, if a patient has diarrhea and has received chemotherapy recently, that should be stated. If radiotherapy has been given, the dates should be indicated so that the pathologist can look out for the acute mucosal changes that occur soon after radiotherapy is begun or the long-term effects that may occur months or years later. Is the diarrhea bloody or nonbloody? Marked nonbloody diarrhea rules out ulcerative colitis.

Questions for the Pathologist

The Chaucerian attitude of bygone days was to hold back information so it would not “prejudice” the pathologist. This is equivalent to asking a clinician to do a physical examination and make a diagnosis without any history to help guide the examination. So much of modern GI pathology diagnosis is correlative.

Many, if not most, pathologists continue to accept biopsy specimens for examination provided with no history and no questions. Asking the right question presupposes knowledge on the part of the endoscopist regarding what biopsy can do in a given setting and what it cannot accomplish. Frequently, the appropriate question can simply be “what is this lesion?” Endoscopists need to have realistic expectations and not force pathologists to be apologists. Biopsy of polyps is a good example. Endoscopists biopsy polyps, and the mucosa is frequently normal. Rather than just saying normal, the histologic diagnosis is frequently collaborationist: (1) polypoid fold, (2) redundant fold, or (3) mucosal tag. These are meaningless terms. Equating the finding of normal mucosa as a polypoid fold may cause worry for patients who see the report and lead to questions every time the individual applies for health, life, and disability insurance. Some pathologists have told me that they are berated or questioned in a hostile manner by endoscopists when a polyp biopsy is signed out as normal. Also, some pathologists have been led to believe that the endoscopist will “get into trouble” if there are too many normal biopsies. That is false. The quality assurance issue with biopsies is whether they are taken according to published guidelines (e.g., American Society for Gastrointestinal Endoscopy) for the indications for biopsy.

The questions for the pathologist may lead the pathologist astray. For example, the question for sessile polyps that are removed during biopsy should simply be “rule out adenoma,” not rule out complete excision. In a sessile polyp biopsy, ruling out total excision requires sectioning and examining the whole dome-shaped biopsy specimen from one end to the other.

When an apparent colon cancer mass or large polyp is found, the dialogue should be: surgical resection is planned; rule out adenomatous change. Asking to rule out cancer may lead to a diagnosis of adenoma but can’t rule out cancer, recommend rebiopsy (see Fig. 5.6 to illustrate this point). By alerting the pathologist that surgery is necessary and asking to rule out adenomatous change, the endoscopist may avoid needless repeat biopsy or having the pathologist examine endless numbers of recuts.

Fig. 5.6 Large tumor of transverse colon seen for the first time. The endoscopist’s biopsy specimens were accompanied by the question of “rule out cancer.” The pathologist’s diagnosis was “adenomatous change, cannot rule out cancer, and recommend rebiopsy.” The endoscopist’s question should have been “large mass, scheduled for resection, rule out adenomatous change.”

Drugs may be responsible for various pathologies that were not imagined previously.¹⁰^–¹² Table 5.2 outlines the information regarding drugs or other therapies that can impact any part of the gut and some that are site-specific. Nonsteroidal antiinflammatory drugs should be in the differential diagnosis of unusual lesions anywhere in the gut, although cause and effect in such instances is often difficult to prove. In lymphocytic or collagenous colitis, drugs may trigger symptoms, and the symptoms may be reversed when the offending drugs are removed.¹³^–¹⁶ The importance of some drugs a patient takes may become apparent only after review of the biopsy results. In ischemic colitis in younger people without generalized atherosclerotic disease, the possibility of a wider range of culpable drugs becomes important, including cocaine and oral contraceptives. These can be sought post hoc after the biopsy results are interpreted.

What Pathologists and Endoscopists Can Do to Improve Communication and Biopsy Diagnoses

Feedback

Poor communication between endoscopists and pathologists was discussed previously. For more than 40 years in the flexible endoscopy era, endoscopists have not asked about the quality of their biopsy specimens or the information pathologists need. Pathologists have complied by never spontaneously bringing up these issues. Endoscopists assume that whatever they have submitted is “adequate” and that none of the biopsy specimens in a group defy interpretation because of small size, superficial scrapings, crush to the villi, or crush of the whole specimen. Endoscopists continue taking rapid-fire biopsy specimens and putting 10 or 12 specimens into a bottle for a given site, and virtually all pathologists go along and embed all the specimens into one tissue block (see Fig. 5.4).

Radiologists ask in requisitions for a brief overview (two lines), and then what should endoscopists rule out? On many pathology requisitions, there may only be a section for clinical history. That may be irritable bowel syndrome or fever of unknown origin. The question on the pathology requisition should be what does the endoscopist want to rule out. Without such information, the pathologist may be left with a rote approach to pathologic diagnosis as opposed to being able to use correlative skills maximally. An example of this inertia is that for some years one of the short courses at the annual meeting of the American Society for Clinical Pathology was “How to Sign out GI Biopsies without Any Clinical Information.” This is quintessential surrender and collaboration of the pathologists to the apathy of endoscopists. This apathy and inertia may compromise patient care.

Modern GI biopsy diagnoses require that the pathologist know the consequences of the diagnoses (e.g., lifelong gluten-free diet for celiac disease; difficulty with life insurance and worry about cancer with ulcerative colitis and Barrett’s esophagus). Differential diagnoses should be focused and not just a standard favored group of differential diagnoses.

Improvements in the Quality of Pathology Reporting

The two most needed improvements in the quality of GI pathology reporting are the following:

1 Avoid calling everything “mild chronic inflammation.” This is a pandemic problem. The pandemic affects nearly all gastric biopsies being signed out as “mild chronic gastritis.” The duodenum and colon are also commonly affected by this widespread pandemic in biopsies that are actually normal.

2 Improve biopsy-processing quality. Biopsy-processing quality is still lacking in many pathology laboratories with regular production of cross-sectioned specimens. Tearing of tissue and poor staining also compromise the ability to make an accurate diagnosis.

Chromoendoscopy

These are exciting times in GI endoscopy. Novel imaging techniques are being tested.¹⁷^–²⁰ They are discussed elsewhere in this book. Optical methods either alone or in combination with chromoendoscopy are likely to hold the key to more targeted biopsies in the search for dysplastic or cancerous mucosa and other mucosal abnormalities. As the technology develops and becomes widely available, chromoendoscopy will become an adjunctive rather than primary tool.

Most endoscopists in the United States do not have access to or use the novel imaging technology. Many do have and use narrow band imaging. In some clinical scenarios, chromoendoscopy with conventional endoscopy may be very useful. With chromoendoscopy, the initial challenge is to learn the difference between normal mucosal variants and the changes that point to the finding of abnormalities such as polyps, cancer in inflammatory bowel disease, early tumors of the stomach and esophagus, and squamous-type or Barrett’s-associated esophageal dysplasia.

A Cochrane Collaboration analysis,²¹ addressed the question of chromoendoscopy versus conventional endoscopy for detection of polyps in the colon and rectum. Five studies were included. There was strong evidence that chromocolonoscopy increased the yield of polyp detection. However, the discussion of the implications for practice correctly cited that the quality of the examination was dependent on complete and careful examination on withdrawal and that training should still focus on this aspect. Speedy withdrawal times have been shown to be one factor contributing to a higher “miss rate.”^22,²³ There is residual debate about this because of varied study designs and because there are no prospective data from the “fast withdrawal era” (<7 minutes). Some clinicians suggest that “less than 7 minutes” is a factor contributing to a greater miss rate of polyp detection.

Some studies of novel imaging or chromoendoscopy end with enthusiastic conclusions that the studies are ready for routine clinical practice. Chromoendoscopy has never caught on widely in the United States. Spraying a whole colon for a polyp hunt or dysplasia is not a simple undertaking for clinicians who have never done it or plan to do it selectively. The learning curve is related to learning which appearances are normal and which are suspect and, for dysplasia, learning to recognize the patterns. There has been a nearly universal reluctance in the United States to employ even the most useful and simple techniques, such as Lugol’s iodine staining of the esophagus to look for dysplastic lesions of the squamous mucosa. Most endoscopy units do not even stock the handful of dyes that can be easily used.

Table 5.3 lists the staining agents and an overview of their staining characteristics and potential utility. There has been a renaissance of research interest in chromoendoscopy worldwide, occurring long after it was developed and first used primarily in Japan. Dyes can help give a landscape view of an area for changes in contour (elevated, depressed) and to define the margins of sessile lesions.

Table 5.3 Stains for Chromoendoscopy and Most Common Current Uses

Dyes That Are Most Useful with Conventional Endoscopy

The three dyes that are most useful with conventional endoscopy are discussed subsequently. Following is an overview.

1 Lugol’s iodine: Lugol’s iodine is an important stain in the search for early squamous esophageal cancer or squamous dysplasia, either in isolation or in association with squamous cancer. Other potential uses are described subsequently in relation to Barrett’s esophagus.

2 Indigo carmine: Indigo carmine is the most widely used dye to highlight subtle changes in terrain, bumpiness, elevations, and depressions. It is a versatile highlighter that can be used throughout the GI tract to give a three-dimensional appearance to visible or suspect lesions and to lesions before endoscopic removal.

3 Methylene blue(MB): MB for duodenal polyps in familial adenomatous polyposis (FAP) is discussed subsequently. MB gives a “terrain view” of the duodenum that makes it much easier to see the sizes and numbers of smaller lesions that are often nearly or totally invisible. This application is also discussed subsequently.

Safety of Dyes

Patients who are to receive Lugol’s iodine should be questioned regarding iodine sensitivity. Application of the dye to iodine-allergic patients may cause a frightening reaction. In Lugol’s staining of the proximal esophagus, it is prudent to have patients intubated so that they do not aspirate the Lugol’s irritant. See the section on MB for a discussion of the controversy concerning safety.

Preparation of the Patient and the Mucosa for Chromoendoscopy

As mentioned, if the use of Lugol’s iodine is contemplated, it should be ascertained that the patient is not allergic to iodine. For MB staining, the patient should be told that the urine and stool might adopt a blue color for 1 or 2 days.

The enemy of good chromoendoscopy is surface mucus, blood, or retained food material. The surface to be examined after application of dye should be washed. For the vital/absorptive dyes (e.g., Lugol’s, MB), it is especially useful to wash with 20 mL or more of 10% N-acetylcysteine. An alternative is to have the patient take a 20,000-U pronase drink before the procedure. This is followed by another wash with water or saline after 1 to 2 minutes, using 100 mL or more of tap water to remove nonabsorbed stain. The washes may also contain a small amount of antifoam solution. Washes may be done using a 60-mL syringe with forceful pressure through the spray catheter or through a syringe without the spray catheter.

The use of an anticholinergic such as glycopyrrolate 0.2 mg intravenously is effective in reducing secretions, and the addition of glucagon (0.25 to 0.50 mg) just before or during the procedure helps to reduce peristalsis and spasm. When taking biopsy specimens from multiple polyps in FAP, after the first few biopsies (e.g., in the third or fourth duodenum), there is often a marked increase in peristalsis. Glucagon (0.25 mg intravenously) stops peristalsis and permits quicker and more biopsy sampling.

Contrast Stains

Contrast stains help most in the delineation of superficial neoplastic lesions, such as in the stomach and of all lesions before endoscopic resection.⁷ In the latter instance, the often irregular margins of the lesion to be excised are better defined. One disadvantage of contrast stains is that it requires some experience to recognize what is normal mucosa and what is not if there are no obviously elevated areas. In the stomach, pit openings and areae gastricae may make the field look abnormal.

The most popular dye stain is indigo carmine used as a contrast stain (see Table 5.3). Although many experts indicate that it should not be washed off after application, some washing off after application leaves the innate color of the lesion in question still preserved (Fig. 5.7). Often all one needs are thin lines of stain in grooves or edges of lesions to define borders and provide a three-dimensional effect (see Fig. 5.7).

Fig. 5.7 A and B, Cluster of confluent colonic bumps. With indigo carmine top right (much of it intentionally washed off), the margins of the lesion are crisp. C, Adenomatous change. This “spreading lesion” needs to be endoscopically removed en bloc.

Other stains can be used for contrast staining. MB is one such dye, provided that there is no intestinal absorptive epithelium because it binds the dye. With ordinary endoscopy, MB as a contrast stain has no advantages over indigo carmine. MB can be used as a contrast stain in a different sense. When saline is being injected before endoscopic resection, a few drops of MB into a 30-mL syringe filled with saline provides a sky blue color to the injected submucosa and provides a better contrast between the lesion to be removed and the uninvolved part of the submucosa below.

Esophagus

Squamous Carcinoma and Dysplasia of the Esophagus

One of the most important potential applications of chromoendoscopy in the clinical arena is in the delineation of squamous carcinoma and dysplasia with Lugol’s solution. The iodine in the solution stains the glycogen in normal squamous epithelium. Negative staining indicates a mucosal disorder that also includes inflammatory change and reactive changes with surface glycogen depletion.

The esophagus is sprayed with 10 to 30 mL of the solution (see Table 5.3). The esophagus can be sprayed efficiently by beginning at the GE junction and applying the spray as the endoscope is moved cephalad. The lumen can be partially collapsed, and when the upper extent of the sprayed area is reached, it can be totally collapsed to permit apposition of the stained walls for more uniform staining. After 1 to 2 minutes, the lumen is insufflated, and any pale-staining areas can be resprayed. The color ranges from dark green to brown to black in normal squamous epithelium. After 10 to 15 minutes, the stain intensity starts to fade, sometimes dramatically.

Areas of dysplasia and carcinoma are glycogen-depleted, so negative staining occurs; this is also true for areas of eroded mucosa, or mucosa markedly thinned by injury or regeneration.²⁴ Examples of mucosa thinned by regeneration are after healing of erosive esophagitis and after restoration of neosquamous epithelium following ablation of Barrett’s esophagus.

With negative staining, Lugol’s highlights areas of dysplasia or early carcinoma that can be missed or poorly visualized in terms of margins (Fig. 5.8A and B). In a study in Linxian, China, which has among the highest rates of esophageal cancer, the rate of dysplasia and cancer detection increased from 62% to 96% with a specificity of 63% with the use of Lugol’s stain.²⁵ The technique is very useful to detect recurrent or metachronous squamous cell esophageal carcinoma.²⁶ It is also useful in patients with head and neck cancers where there is an increased risk of squamous cell esophageal cancer.²⁴

Fig. 5.8 A and B, Comparison of the appearance of squamous cancer before (A) and after (B) Lugol’s staining. Lugol’s-stained mucosa provides crisp definition of the margins of the lesion and its extent. C and D, Two small nonstaining areas after ablation for Barrett’s esophagus. At this stage, they do not require biopsy, just “touchup” ablation.

Residual Islands of Nonsquamous Mucosa after Ablation of Barrett’s Esophagus

Lugol’s makes it simple to do “final checks” for nonsquamous islands after ablation. These islands may be invisible in the unstained state (Fig. 5.8C and D). Neosquamous postablation mucosa is thinner initially, with less glycogen. It may be paler than usual with Lugol’s staining but not completely negative. I use Lugol’s iodine as the final “gold standard” for complete return of neosquamous epithelium after ablation of Barrett’s esophagus.

Methylene Blue

Sprayed MB induces oxidative damage of DNA when it is photosensitized by white light.²⁷^–²⁹ The concern in Barrett’s esophagus is that the stain may further the promutagenic DNA damage that may already exist, and this raises the question about increased rate of carcinogenesis. This situation is controversial with vigorous arguments²⁸ that the studies of cellular damage used higher doses for longer than the conventional spray at endoscopy and other variables. To resolve this controversy, cellular damage or lack of it needs to be studied in a fashion that is comparable in dose and duration to MB as used in chromoendoscopy.

MB staining is and will be used even more as an adjunct to novel imaging techniques. It has been used alone in research studies of Barrett’s esophagus with conventional endoscopy (Fig. 5.9). Canto and colleagues³⁰ did much of the seminal work with MB. MB binds to intestinal absorptive epithelium, be it normal small intestine or the intestinal metaplasia that is characteristic of Barrett’s esophagus and intestinal metaplasia of the stomach.

Fig. 5.9 A and B, Long-segment Barrett’s esophagus before and after methylene blue staining. Staining intensity is dark and uniform. C and D, Short-segment Barrett’s esophagus before and after methylene blue staining. Staining intensity is lighter and more patchily distributed.

Methylene Blue Procedure

First, a mucolytic is given (N-acetylcysteine or pronase, the latter more commonly in Japan). Next, 0.5% MB is sprayed with a spray catheter, and 2 minutes later the mucosa is washed off. One should avoid staining clothing, and patients should be told not to be concerned by the passage of blue or green urine in the next 1 or 2 days. There is an acknowledged learning curve, and the staining procedure adds 2 to 12 minutes to the procedure and on the order of 10 to 15 minutes if one includes setup and postprocedure cleanup times and learning curves. Canto advised that beginners in chromoendoscopy take multiple photographs and compare staining characteristics with pathologic diagnoses of biopsy specimens of stained areas.³⁴

In Barrett’s esophagus, there are two areas of interest in studies with MB. One is to identify intestinal epithelium (positive staining) in apparent or possible short-segment Barrett’s esophagus, and the second is to detect dysplasia by negative staining. With conventional endoscopy, a meta-analysis failed to show superiority of MB (to provide targeting of areas for biopsy) over random four-quadrant biopsy.³¹ In a prospective randomized crossover trial, the dysplasia detection rate was similar with MB versus four-quadrant biopsy.³² The miss fraction for dysplasia was 5/21 with MB and 3/21 with four-quadrant random biopsy. Fewer biopsy specimens were taken in the MB group (for targeting), however. MB may be useful in trying to define the region around the LES to determine whether there are short tongues of Barrett’s esophagus above a normally positioned Z line.

Short-Segment Barrett’s Esophagus and Intestinal Metaplasia of the Cardia

If biopsy specimens of apparent 2-cm tongues of Barrett’s esophagus at endoscopy are found histologically to have intestinal-type goblet cells, the diagnosis of short-segment Barrett’s esophagus is made. If intestinal-type goblet cells are absent, Barrett’s esophagus should not be diagnosed. Staining with MB in suspected short-segment Barrett’s esophagus is intended to help increase the yield in biopsies of areas with intestinal metaplasia (blue staining) to clinch the diagnosis.

When used for the detection of short-segment Barrett’s esophagus (≤3 cm in length), the staining pattern is less diffuse and patchier than cephalad than in longer segments of Barrett’s esophagus (see Fig. 5.9). The reason is that in short-segment Barrett’s esophagus there is a greater mix of intestinal and nonintestinal columnar cells present than in the more diffuse intestinal change of long-segment Barrett’s esophagus.^33,³⁴ In the final analysis, the finding rate of intestinal-type goblet cells in short-segment Barrett’s esophagus of the tongue variety is no greater than targeted biopsies without chromoendoscopy. Fewer biopsies may be needed, so the main value is for clinicians who like it because it is a “biopsy aversion technique.”

MB staining has also been used to identify intestinal metaplasia of the cardia right at the GE junction in patients without endoscopically visible Barrett’s esophagus. In practice, there is no reason to biopsy a normal-appearing Z line. Intestinal metaplasia may occur in 30% of individuals with GERD and no Barrett’s esophagus. It is also common in individuals with no GERD.⁹ Its presence is not an indication for biopsy surveillance.

High-Grade Dysplasia and Endoscopically Invisible Adenocarcinoma

Studies with MB (with or without acetic acid) for detecting dysplasia or early cancer in Barrett’s esophagus generally have an adjunctive role coupled with novel imaging methods.³⁵^–³⁸ Acetic acid (1.5%) blanches the esophagus white and leaves Barrett’s esophagus and gastric mucosa looking red. The objective is to target the areas most likely to contain neoplastic change and to reduce the numbers of random biopsies. Well-designed larger prospective studies are needed to settle whether these dyes with novel imaging have any advantage over dyes with conventional endoscopy.

Summary: Dye Staining in Barrett’s Esophagus

Given the available data and the extra time involved, MB or other dye techniques for detecting intestinal metaplasia and dysplasia are not likely to be incorporated into routine clinical practice in the United States.

Stomach

Apart from the use of contrast stains to detect subtle lesions or to define the margins of lesions ³⁹ with or without novel imaging, there is no type of chromoendoscopy that has widespread applications in the stomach. MB stains intestinal metaplasia of the stomach a dark blue, and it has been combined with magnification endoscopy to examine its utility in more precise characterization of intestinal metaplasia and gastric dysplasia.^40,⁴¹

Small Intestine

Celiac Disease

The endoscopic signs of celiac disease include decreased numbers of valvulae, scalloped valvulae, a mosaic pattern, and visualization of underlying blood vessels. A host of new imaging technologies are being examined in celiac disease, including some with dyes such as MB or a contrast stain.⁴²

If the objective is to rule out celiac disease, biopsy specimens from three sites in the duodenum should be taken to rule out patchy involvement with lesions of lesser severity: mid–second duodenum, third duodenum, and fourth duodenum or proximal jejunum. Dye stains are generally not helpful nor worth the extra time. Biopsy specimens should be taken even if the mucosa looks normal.

Other Small Bowel Lesions

Nowhere is MB more useful than in the assessment of the duodenal sweep in patients with FAP or more atypical polyposis syndromes. Some lesions are easily visible; however, most duodenal adenomas in FAP are flat, often along valvulae, and barely raised if at all. MB stains the nondysplastic mucosa deep blue and leaves dysplastic areas unstained. Spraying of the whole duodenum permits a sweeping view of the terrain for targeting biopsy (Fig. 5.10). This stain or a contrast stain, such as indigo carmine, may be very useful before endoscopic resection of one or more of these lesions.

Fig. 5.10 Small intestinal chromoendoscopy. A and B, Typical flat to minimally raised adenomas in duodenum typical of adenomas seen in familial polyposis coli. They are easily highlighted and more readily recognized with methylene blue staining. Methylene blue stains intestinal mucosa and leaves adenomas negatively stained.

Colon

Polyps of the Colon

Chromoendoscopy has been directed toward two aspects of polyps of the colon. One is to determine the difference between hyperplastic and adenomatous polyps on gross examination. The second is to increase the detection rate, especially of adenomas. The favorite stain has been indigo carmine spray, with or without magnifying endoscopy or high-resolution endoscopy. Other creative approaches to dye staining have put the dye into the electrolyte purging solution or into capsules.^43,⁴⁴

Hyperplastic Versus Adenomatous Polyps

A pit or pitted pattern denotes a hyperplastic polyp, and a grooved or sulcus appearance denotes adenoma. Most of the pioneering work in this area was done in Japan.⁴⁵ Among numerous studies examining the potential of chromoendoscopy has been a U.S. prospective multicenter study, in which 92.3% of the polyps could be classified according to the dye staining pattern. For adenomatous polyps, the sensitivity, specificity, and negative predictive values were 82%, 82%, and 88%.⁴⁶

Increased Detection Rate of Adenomas

Flat and depressed adenomas refer to adenomas that are raised but pancakelike (with or without depressed centers) and not generally dome-shaped. One endoscopic definition that has been used is that they are either flat or depressed lesions with a height less than half of the diameter of the lesion.⁴⁷ To prove that they were not just a Japanese phenomenon, a Japanese endoscopist, Saitoh, who was experienced in the detection of these lesions, was recruited to the United States to perform a study using indigo carmine and conventional endoscopy. He did left-sided colonic indigo carmine staining from splenic flexure to rectum for colonoscopies in 211 patients.⁴⁷ Flat and depressed lesions were found in 22.7%. These were more likely adenomas than hyperplastic polyps (87% vs. 67%), and the advanced lesions with high-grade dysplasia or cancer were significantly smaller than comparable conventional polypoid lesions (10.75 mm vs. 20 mm). In a randomized controlled trial of 259 patients using total colonic dye spray, more diminutive adenomas were detected proximal to the sigmoid colon, and more patients were identified with three or more adenomas.⁴⁸ Increased detection rates with indigo carmine staining were also found in a study in Korea, a country with a lower incidence of colorectal neoplasia compared with Western countries.⁴⁹

Application in Practice

The distinction of hyperplastic from adenomatous polyps holds some appeal, especially proximal to the rectum and distal sigmoid colon. In the latter distal locations, hyperplastic polyps may be numerous and easy to identify as such because of their whitish or neutral appearance. Colon dye spray adds time to the colonoscopy procedure; it requires a motivated endoscopist and gaining of a certain amount of experience. It remains to be seen whether their use in prospective studies will find carcinomas at an earlier stage or whether optical techniques alone that can scan the mucosa will be the answer for easier detection (e.g., narrow band imaging). The greatest theoretical potential for any optical aid is in finding flat adenomas in the 8- to 10-mm range that contain carcinoma. It is unknown how many of these would be missed by experienced endoscopists with conventional colonoscopy; also, the temporal biologic behavior of these lesions is unknown.

Chromoendoscopy and Inflammatory Bowel Disease

Chromoendoscopy was studied in a randomized controlled trial of 174 patients with long-standing ulcerative colitis comparing conventional surveillance biopsy with total spray of the colon with MB.⁵⁰ Investigators compared 32 lesions with intraepithelial neoplasia (24 of 32 low grade; 24 of 32 in flat mucosa) in the dye group with 10 lesions (8 of 10 low grade; 4 of 10 in flat mucosa) in the conventional endoscopy group. The dye spray group also predicted the degree of histologic inflammation better than the conventional group, but that is not the primary message.⁵¹

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