Cancer of the Rectum

Published on 04/03/2015 by admin

Filed under Hematology, Oncology and Palliative Medicine

Last modified 04/03/2015

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 1029 times

Chapter 78

Cancer of the Rectum

Summary of Key Points

Staging and Assessment

• Careful rectal examination yields 67% to 84% accuracy in staging (superficial, mobile, tethered, fixed) and should include pelvic examination for women and prostate examination in men.

• Rigid proctosigmoidoscopy provides the most accurate assessment of distance, size, and position, as well as tethering to surrounding structures.

• Colonoscopy, colonography, or double-contrast barium enema is used to assess for synchronous colon tumors.

• Endorectal ultrasound can assess the depth of invasion and nodal status. Nodal assessment is less reliable.

• Magnetic resonance imaging (MRI) with endorectal coil and ultrasound are useful to stage rectal cancer and are more sensitive and specific than computed tomography (CT) alone. MRI is used to assess locally advanced or recurrent local disease. CT should be performed on all patients to assess intraabdominal spread. CT or chest x-ray is required to evaluate for synchronous lung metastases.

• The liver is the most frequent site of distant spread, followed by lung, retroperitoneum, ovary, and peritoneal cavity.

• Baseline carcinoembryonic antigen (CEA) levels are assessed and followed postoperatively, even if initially normal.

Treatment

• Goals of treatment are cure, local control, and quality of life.

• All retrorectal tumors should be resected, and preoperative biopsy must be avoided.

• Full-thickness local excision is feasible for highly selected patients with T1 mucosal, submucosal, and early invasive cancer, particularly in patients with high-risk comorbidities.

• For T1 to T3 rectal adenocarcinomas, surgical procedures are total mesorectal excision, low anterior resection, low colorectal or coloanal anastomosis with J pouch, and abdominoperineal resection, leaving at least a 2-cm distal margin and clear lateral margins. With surgery, mortality rates are 1% to 7% and morbidity rates are 13% to 46%. The survival rate at 5 years is 74% to 87%.

• Combined therapy cures 50% of N1 patients; 25% of tethered or fixed rectal cancers treated by neoadjuvant chemoradiotherapy are subsequently resected and cured.

• Of patients who die of rectal cancer, 25% fail with pelvic disease only.