To the Editor.
—In his paper "Resection of Rectosigmoid for Small Tumors" (Arch Surg92:943 [June] 1966), Dr. Bjorn Thorbjarnarson has described a method to identify the level of a nonpalpable tumor of the rectum or rectosigmoid from within the abdomen. This is done by having an assistant introduce a proctoscope through the anus to the level of the lesion, palpating the instrument from within the abdomen, and marking the appropriate level with a suture in the bowel wall.An alternative method is one which I have used successfully for several years. After anesthesia has been induced and before the abdomen is prepared or draped, the proctoscope is introduced through the anus and the distance between the anal verge and the lowed level of the lesion is determined from the calibrated marking on the instrument. The proctoscope is then removed. This distance is then measured on a large caliber,