Villous adenomas of the colorectum.

During a ten-year period 258 patients with villous adenomas were seen at the Massachusetts General Hospital: seventy-four of these patients (29%) had invasive cancer that developed in adenomas. The operative mortality ascribed to removal of benign adenomas was zero, but for cancer arising in villous adenomas it was 3 per cent. Therapy often is difficult because of the size and location of the tumors. Methods of removal have been considered in detail.