ABSTRACT
The general mechanisms of spread for carcinoma of the rectum are similar to those of the colon, but because of the rectum’s location within the pelvis, it is appropriate to elaborate on these mechanisms, especially as they may pertain to treatment. Many carcinomas of the rectum produce no symptoms initially and are discovered only as part of a routine proctosigmoidoscopy. An intravenous pyelogram is still advised by some surgeons in patients with carcinoma of the rectum to outline the anatomy of the ureters, evaluate renal function, and reveal obstructive uropathy. Ultrasonographic images of the normal colon and rectum identify five distinct layers: mucosa, mucosa and muscularis mucosae, submucosa plus interface between submucosa and muscularis propria, muscularis propria minus the interface between the submucosa and muscularis propria, and serosa and perirectal fascia. The operation, which entails removal of the sigmoid colon and anastomosis of the proximal sigmoid or descending colon to the proximal rectum, is probably better-called a sigmoid resection.
