LONG-TERM SURVIVAL AFTER TREATMENT OF MALIGNANT COLONIC POLYPS

PURPOSE: This study was designed to evaluate the longterm outcome and survival of patients treated for malignant colonic polyps. METHODS: A retrospective review of 15,975 cases of colonoscopies with 8,685 endos copic polypectomies performed between 1972 and 1990 was undertaken. In 65 patients, the polypectomy specimens contained invasive carcinoma. Six patients were excluded (follow-up, <6 months). Polyp data, operati ve findings, and follow-up on the remaining 59 patients were recorded. RESULTS: Malignant polyps were found in 35 males and 24 females who h ad an average age of 64 (range, 39-81) years. Follow-up ranged from 12 to 202 (mean, 90) months. Tumor differentiation was poor in one and w ell or moderately differentiated in 58 patients. Positive or indetermi nate margins were found in 13 patients. Thirty-seven (63 percent) pati ents were managed with polypectomy and surveillance. Four of these (wi th rectal tumors) also had an additional local excision for questionab le margins. One recurrence was noted in a patient who refused surgery, which was recommended because of indeterminate margins. Twenty-two pa tients (37 percent) underwent colectomy. Indications included Haggitt Level 3 or 4 invasion (19), inadequate margins (7), patient preference (1), and poor differentiation (1). Residual disease was found in cole ctomy specimens of three patients (14 percent). There were no cancer-r elated deaths in either treatment group. Life table analysis demonstra ted a five-year survival of 82 percent for the colectomy group and 95 percent for the polypectomy group (P = 0.15). CONCLUSION: Treatment of patients with malignant polyps must be individualized based on evolvi ng criteria. Patients in whom polypectomy margins are inadequate shoul d undergo colectomy. With appropriate selection criteria, patients sel ected for colectomy had a five-year survival rate similar to the rate of those treated by polypectomy alone.