<prompt> In rectal cancer, the distal clearance margin should be at least2 cm3cm4 cm5 cm  <response>: Tumor margin for curative resection IN GI malignancies Stomach, small intestine, colon and proximal rectum, tumor margin for curative excision is 5 cm except Esophagus : 10 cm Distal rectum : 2 cm Ref: Sabiston 20th edition Pgno : 1378 