Incidence and therapeutic implications of synchronous colonic pathology in colorectal adenocarcinoma

The presence of synchronous benign and malignant colonic pathology may influence the magnitude of surgery for colorectal adenocarcinoma. The aim of this prospective study was to quantitate the need for a more extensive surgical procedure because of synchronous pathology in colorectal cancer patients.

Between 1984 and 1996, 235 consecutive patients were treated for colorectal adenocarcinoma. Preoperative survey of the colon in 228 patients included colonoscopy (91%) and double contrast barium enema (35.7%). Seven patients were excluded for incomplete preoperative survey because of perforating or obstructing colon carcinoma or acute ulcerative colitis.

One hundred four patients (45.6%) had the following synchronous colonic lesions: benign polyps (68 patients, 29.8%), diverticular disease (30, 13.1%), ulcerative colitis (10, 4.4%), synchronous adenocarcinoma (8, 3.5%), and Crohn's colitis (3, 1.3%). Pathologic examination demonstrated three additional synchronous adenocarcinomas for a total of 11 patients (4.9%). Twenty-five (11%) required more extensive surgery than dictated by the primary cancer. Of these 25 patients, 17 had a benign or premalignant condition associated with their carcinoma and 8 had a synchronous carcinoma. Seventeen patients underwent a sphincter-saving procedure. Of the remaining eight patients requiring sphincter ablation, seven were needed because of a synchronous nonmalignant lesion, rather than because of the primary tumor.

In our patient population, the incidence of synchronous colorectal lesions was 45.6%. Synchronous colorectal cancer occurred in 4.9%. In 11%, the presence of synchronous colorectal lesions made the surgical procedure more extensive than that dictated by the primary cancer, and in 3%, the need for a sphincter ablating procedure was dictated by a synchronous nonmalignant lesion.