Adequacy of "hot biopsy" for the treatment of diminutive polyps: a prospective randomized trial.

Patients with diminutive polyps in the rectum or sigmoid colon were randomized to "hot biopsy" treatment for either 1) electrocautery for 2 s (fixed duration cautery) or 2) cautery until visible necrosis of the polyp base was evident (variable duration cautery). Sigmoidoscopy was performed 4 wk after treatment to determine the adequacy of polyp eradication. In the fixed duration cautery group, 11 of 21 polyps (52%) were eradicated, compared with 12 of 14 polyps (86%) in the variable duration cautery group (p = 0.04). When analyzed according to whether or not visible necrosis was achieved (some of the polyps in the fixed duration cautery group showed necrosis with 2 s cautery), 19 of 23 polyps (83%) were eradicated when necrosis was evident, compared to 5 of 12 (42%) without necrosis (p = 0.004). We conclude that hot biopsy treatment for diminutive polyps is significantly more effective when visible necrosis is achieved during cautery. Furthermore, even with visible necrosis, there is a 17% failure rate of polyp eradication.