Rare synchronous colorectal carcinoma with three pathological subtypes: A case report and review of the literature.

backgroundSynchronous colorectal carcinomas (SCRC) are two or more primary colorectal carcinomas identified simultaneously or within 6 mo of the initial presentation in a single patient. Their incidence is low and the number of pathological types of SCRC is usually no more than two. It is very unusual that the pathological findings of a patient with SCRC show more than two different pathological subtypes. Here, we report a rare case of SCRC with three pathological subtypes. CASE SUMMARY: A 75-year-old woman who had no previous medical history or family history was admitted to the hospital because of intermittent hematochezia for more than a month. Colonoscopy displayed an irregularly shaped neoplasm of the rectum, a tumor-like lesion causing intestinal stenosis in the descending colon, and a polypoidal neoplasm in the ileocecum. Subsequently, she underwent total colectomy, abdominoperineal resection for rectal cancer, and ileostomy. After operation, the pathological report showed three pathological subtypes including well-differentiated adenocarcinoma of the ascending colon, moderately differentiated adenocarcinoma of the descending colon, and mucinous adenocarcinoma of the rectum. She is now recovering well and continues to be closely monitored during follow-up.

conclusionPreoperative colonoscopy examination, imaging examination, and extensive intraoperative exploration play important roles in reducing the number of missed lesions.