EXPERT ANALYSIS AT THE ASCRS ANNUAL MEETING

LOS ANGELES (FRONTLINE MEDICAL NEWS) – In the clinical experience of Dr. Ian C. Lavery, prevention efforts are the best defense against local recurrence of rectal cancer.

“This means adjuvant treatment, if necessary, neoadjuvant treatment, and a meticulous surgical operation,” Dr. Lavery of the department of colorectal surgery at the Cleveland Clinic said at the annual meeting of the American Society of Colon and Rectal Surgeons. “If the circumferential resection margin is negative, the local recurrence rate is 10% or less. If it’s positive, local recurrence goes up to 78%. Even when we attempt to do the perfect total mesorectal excision, local recurrence is in the order of 4%.”

Selective use of radiotherapy in the neoadjuvant setting appears to be reducing the incidence of local recurrence, “certainly in the short term,” he added. “In the long term, I’m not sure we know the true answer to that yet. Using other techniques like washing the rectal stump out, the use of stapling, and en-bloc resection if necessary [can help prevention efforts].”

The incidence of local rectal cancer recurrence is reported to be between 3% and 50%, but neither curative nor palliative treatment is standardized. “When you get local recurrence after a rectal cancer operation, it’s a disaster,” Dr. Lavery said. “It may cause intractable pain, bleeding, perforation, obstruction, and sepsis – all incredibly difficult things to manage.”

Patients who develop a local recurrence of rectal cancer are often asymptomatic. A digital rectal exam (DRE) may or may not identify a recurrence and carcinoembryonic antigen levels are helpful on some occasions. According to Dr. Lavery, optimal surveillance consists of a clinical examination including DRE, endoscopy, blood tests, CT scans, MRI, and PET scans. “If they were all to be done routinely it would increase the detection earlier rather than later,” he said.

CT and MRI appear to be about 85% accurate but both modalities are “very poor at detecting peritoneal disease,” he said. PET scans for recurrent carcinoma have been shown to change the management in 20%-56% of cases ( Ann Surg Oncol. 1997 Dec; 4:613-20 ).

While follow-up of patients who have undergone surgery for local rectal cancer is generally favored, there is no consensus on what the ideal follow-up timeline should be. “In my opinion, the more intensive follow-up is going to be better than the cursory conventional follow-up examination,” Dr. Lavery said. “One of the big reasons for that is the vast majority of recurrences are extraluminal so they may be difficult to feel. Doing endoscopy, you can’t see them if they’re extraluminal.”

The goal in treating recurrent rectal cancer is to improve quality of life, he continued, as the common symptoms include obstruction, pain, bleeding, bowel discharge, or perforation/abscess. Optimal treatment involves striving for tumor-free margins after the operation. “This may require en bloc resection of an adjacent prostate, bladder, lateral pelvic wall,” he said. “But clinically and radiologically, it’s very difficult to identify those patients that have a potentially R0 resection.”

Curative treatment is possible if the recurrence is locally resectable and the patient has minimal comorbidities. “The potential morbidity after the surgery has to be acceptable, considering the severity of the problem that we’re dealing with,” Dr. Lavery noted. “Distant disease also complicates the issue.”

Reasons to avoid resection include rigid tumor fixation, leg lymphedema, major vessel encasement, bilateral ureteric involvement, extensive para-aortic lymph node involvement, and radicular pain. “If you embark on one of these cases, you want to make it at least the first if not the only case of the day,” Dr. Lavery advised. “Anticipate the need for assistance during the operation, but above all, make sure you have optimal exposure to do the surgery.” He reported having no financial disclosures.

dbrunk@frontlinemedcom.com

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