Timing of colonoscopy after resection for colorectal cancer: are we looking too soon?

BACKGROUND: Based on current National Comprehensive Cancer Network guidelines, colonoscopic surveillance after colorectal cancer resection should begin at 1 year. OBJECTIVE: The aim of this study was to determine whether the incidence of cancer or advanced polyp detection rate was high enough to justify colonoscopy at 1 year. DESIGN: The Ochsner Clinic Tumor Registry Database was queried for patients who underwent a segmental colectomy or proctectomy between 2002 and 2010. Patients who had a preoperative colonoscopy and at least 1 documented postoperative colonoscopy were included. We considered new cancer or polyps of ≥1 cm as missed on the preoperative colonoscopy. Patients with an identified genetic trait causing a predisposition to colorectal cancer were excluded. RESULTS: Five hundred twelve patients underwent resection, and 155 met our inclusion criteria. The average age was 64 years, and 53% patients were male. There were 32.9% with stage I disease, 35% with stage II disease, 27.1% with stage III disease, and 5.2% with stage IV disease. Of these patients, 52.2% had a right colectomy, 7.1% had a left colectomy, 16.8% had a sigmoid colectomy, 22% had a low anterior resection, and 1.3% had a transanal resection. The average time to first postoperative colonoscopy was 478 days (SD ±283 days). Twenty-four patients had adenomatous polyps detected on their first surveillance colonoscopy, but only 5 (3.2%) polyps were ≥1 cm, and there was no correlation between stage of cancer and finding a polyp. No new cancers were detected, but 3 (1.9%) had an anastomotic recurrence. CONCLUSIONS: The performance of surveillance colonoscopy at 1 year resulted in the detection of only 5 missed polyps ≥1 cm and no metachronous cancers. Anastomotic recurrences were rare, and the majority were in patients who had rectal cancer that could be evaluated by in-office flexible sigmoidoscopy. Extending the time to first colonoscopy appears to be safe and would help conserve valuable resources, including physician and facility time, which is imperative in the current health care climate.

The effects of perfusion on an amputated extremity.

The amputated hindquarters of adult female rats were infused with solutions of lactated Ringer's, Collins hypertonic renal perfusate, and dextran-dextrose on a washout and continuous basis. The perfusate was analyzed for energy compounds and breakdown products and the muscle tissue examined histologically. Intermittent perfusion or injection under pressure led to marked edema in a 4-hour period and was abandoned in favor of a system that perfused the part at 120 to 150 cm H2O. The model perfused with Collins gained an average of 1.35 gm, that with lactated Ringer's 2.35 gm, and that with dextran-dextrose lost 2.35 gm. Pressure graphs of the various solutions indicated that the vascular bed reacts more physiologically to Collins solution and dextran-dextrose than to lactated Ringer's. Histologic sections of the muscle biopsies confirmed this. The release of ATP and hypoxanthine with lactated Ringer's suggests that it is the most damaging of the perfusates. These findings support the results of the pressure graphs and histologic studies. A potential for replantation of amputated limbs that contain muscle when the cold ischemia time may exceed 6 hours is suggested by the data presented.