The relationship between the extent of distal clearance and survival and local recurrence rates after curative anterior resection for carcinoma of the rectum.

With increasing use of low anterior resection, the length of rectum removed below the tumor is often less than the recommended 2 to 5 cm. It is important to know if this decreases the chance of cure. Between 1963 and 1975, 334 patients survived radical restorative operations for single rectal adenocarcinoma. The length of rectum below the tumor measured on fixed pinned-out pathologic specimens was 2 cm or less in 55 patients (group 1), 2 to 5 cm in 177 (group 2), and 5 cm or more in 102 (group 3). The Dukes' classification, histologic grade, and extent of local spread of the tumors were similar in the three groups. Overall crude 5-year survival rates for groups 1, 2, and 3 were 69.1%, 68.4%, and 69.6%, respectively. Corresponding cancer-specific death rates were 25.5%, 23.2%, and 21.6%. These rates were also similar in matching pathologic subgroups of the three main groups. Of 23 observed or suspected local recurrences, there were four recurrences in group 1 (7.3%), 11 in group 2 (6.2%), and eight in group 3 (7.8%). These results suggest that a margin less than 2 cm below a rectal carcinoma does not affect survival or local recurrence adversely.