Simple cysts and polycystic liver disease: Surgical and nonsurgical management

Published on 10/04/2015 by admin

Filed under Surgery

Last modified 10/04/2015

Print this page

rate 1 star rate 2 star rate 3 star rate 4 star rate 5 star
Your rating: none, Average: 0 (0 votes)

This article have been viewed 1982 times

Chapter 69B Simple cysts and polycystic liver disease

Surgical and nonsurgical management

Single Cysts

Asymptomatic liver cysts, even when large, need no treatment and do not require surveillance. A small percentage of patients have symptoms related to an increase in the size of cysts (see Chapter 69A). Caution must be exercised when considering whether a simple cyst is symptomatic when it is smaller than 8 cm or when it does not protrude outside of the liver surface. If this is not the case, or if symptoms are vague, ultrasound-guided aspiration of the cyst may be attempted as a therapeutic test. If this does not result in improvement of symptoms, further treatment is not required. When aspiration is effective at relieving symptoms, the cyst is symptomatic. Improvement, however, is transient, as the cyst inevitably recurs after simple aspiration (Saini et al, 1983), and more radical treatment, such as sclerotherapy or fenestration, can be considered.

It is unclear whether treatment is indicated in patients who are asymptomatic but nevertheless have evidence on imaging of compression of the bile ducts, or of portal or hepatic veins, by the cysts. If these anomalies are unilateral—that is, at least one hemiliver has normal biliary drainage and normal inflow and outflow—our opinion is that treatment is not required, as the stenosis is not always reversible (Fig. 69B.1).

Treatment of symptomatic cysts relies on the destruction of the epithelial lining (sclerotherapy) or on the creation of a communication between the cyst and the peritoneal cavity (unroofing, also known as fenestration). Sclerotherapy is performed under ultrasound (US) guidance, whereas unroofing is currently mostly performed by laparoscopy. Hence symptomatic patients today are most likely to undergo a minimally invasive procedure. This should not lead to an extension of the indications because complications, occasionally severe ones, may occur. It is also important to warn patients early on that these treatments aim at transforming a large, symptomatic cyst into a small, asymptomatic one, and that they should not worry if some anomalies persist on imaging after the procedure.

Sclerotherapy

Method

Sclerotherapy aims at destroying the epithelium lining the inner surface of the wall to stop intracystic fluid secretion (see Chapter 28). Under US guidance, the cyst is located and punctured, and a small drainage catheter is introduced by the Seldinger technique. Injection of water-soluble contrast media ensures that no communication with the bile duct exists and that no leak into the peritoneal cavity is present, both of which are contraindications (Tikkakoski et al, 1996).

The most frequently used sclerosing agent is 95% ethanol, as for renal cysts. Minocycline hydrochloride, otherwise used for pleurodesis or, more recently, ethanolamine oleate (Miyamoto et al, 2006; Nakaoka et al, 2009) have been proposed as alternatives. Radiofrequency ablation (RFA) has also been performed, although reports are only anecdotal.

The amount of ethanol injected should be limited because alcohol sclerotherapy is associated with an increase in blood alcohol concentration, peaking 3 to 4 hours after treatment (Yang et al, 2006). As massive ethanol intoxication leading to coma has been reported after injection of 240 mL in a 3500 mL cyst (Wernet et al, 2008), the volume of alcohol should not exceed 100 to 120 mL. To ensure that the sclerosant comes in contact with the entire surface, the patient is rolled in different positions. Alcohol is then aspirated and the catheter removed. The procedure is performed with the patient under light general anesthesia because it is painful.

Several protocols have been designed that differ in the duration of alcohol retention in the cyst (from 10 to 240 minutes) and in the number of sessions (single or multiple) (Larssen et al, 2003; Simonetti et al, 1993; Tikkakoski et al, 1996; Yang et al, 2006). Comparative studies are lacking, but a single study showed that 120- and 240-minute retention times yield comparable results (Yang et al, 2006).

Recently, prolonged catheter drainage with negative pressure of the cyst without sclerotherapy has been shown to be as effective as alcohol injection in a randomized study (Zerem, 2009). This result mainly shows that an important aspect of percutaneous treatments in general is to achieve collapse of the cystic cavity.

Fenestration

Method

The surgical treatment of choice for a single, large, symptomatic cyst is fenestration that consists of an excision of the roof of the cyst to establish a large communication between the cyst and the peritoneal cavity. Fluid continues to be produced by the epithelial lining, but it is reabsorbed by the peritoneum and the cyst cavity collapses. This treatment is extremely simple because symptomatic cysts are virtually always large and have a protrusion of part of their wall outside the liver. Only the protruding part of the cyst wall should be excised; there is no need to enter the liver parenchyma, which is the main cause of intraoperative and postoperative bleeding of biliary leaks, nor is there a need to remove the cyst completely.

The procedure has been described by laparotomy but is currently most often performed by laparoscopy, which offers the advantage of being less invasive and ensuring a quicker recovery. A pneumoperitoneum is established, the cyst is punctured and incised with either scissors or electrocautery, and the cyst wall is widely excised. If transection is performed along a thin part of adjacent parenchyma to ensure a wider opening—that is, if the protruding part of the cyst is small—endovascular staplers may occasionally be used to secure vasculobiliary structures that are compressed at the periphery of the cyst wall. The internal lining of the cyst is examined, and if a biliary communication is suspected, intraoperative cholangiography should be performed. Some investigators have advocated treating the remnant cyst epithelium by argon laser beam coagulation or electrocoagulation to destroy the epithelium. In any case, the excised portion of the cyst is sent for pathologic analysis. Suction drainage is optional.

Complications

The most severe intraoperative complication is bleeding, and transfusion has occasionally been required (Loehe et al, 2010). This occurs when the liver parenchyma, not the cyst wall, is opened. Conversion, the most frequent indication for which is bleeding, is required in less than 5% of patients.

Postoperative complications are rare, and patients are usually discharged after 1 to 3 days. No deaths have been reported, and morbidity ranges between 0% and 15% (Gall et al, 2009; Loehe et al, 2010). The most severe complications include biliary leak and hemorrhage, which result from reexpansion of biliary and vascular structures that were compressed at the interface between the cyst wall and the parenchyma and that were inadequately secured. If the periphery of the opened cyst is thick, it should be closed with running sutures; an alternative is to use an endovascular stapler on these portions of the cyst wall because it allows wide fenestration while maintaining hemostasis. Ascites is very rare after fenestration of simple cysts, unlike PCLD (see below).

Polycystic Liver Disease

Symptoms in PCLD are related mainly to the volume of the entire liver rather than to the volume of a specific cyst. Although palliation with percutaneous alcohol sclerotherapy or laparoscopic fenestration has been reported, neither proves effective in the long term in the most frequent forms of PCLD (Robinson et al, 2005). The aim of treatment is instead to decompress and reduce the size of the entire liver or to remove as many cysts as possible. In highly symptomatic patients, these objectives can be achieved by open fenestration, liver resection, or liver transplantation. Patients should be carefully informed of the limitations and risks of these procedures. Medical alternatives have been recently introduced, although larger studies are required to confirm their clinical impact.

Nonsurgical Treatments

Medical Treatment

Somatostatin Analogues

Cyclic adenosine monophosphate (cAMP) is a potent mediator of cholangiocyte proliferation and secretion of fluid into cysts (see Chapter 69A). Somatostatin receptors are expressed on cholangiocytes; when triggered, this activates a signaling cascade that suppresses cAMP. Somatostatin blunts hepatic cyst expansion by blocking secretin-induced cAMP generation (Masyuk et al, 2007). It also suppresses the expression of insulin-like growth factor 1 (IGF-1), vascular endothelial growth factor (VEGF), and other cystogenic growth factors and downstream signaling from their receptors (Pyronnet et al, 2008). Two randomized controlled trials have recently demonstrated that 6 or 12 months of treatment with lanreotide, a long-acting somatostatin analogue, was associated with a significant reduction of liver volume in patients with PCLD, with or without autosomal dominant polycystic kidney disease (ADPKD), compared with placebo-treated controls (Hogan et al, 2010; van Keimpema et al, 2009

Buy Membership for Surgery Category to continue reading. Learn more here