Multiple colorectal carcinomas and colorectal carcinoma associated with extracolonic malignancies.

In this study, we analyzed 149 surgical cases of colorectal cancer between January 1983 and August 1989. Thirteen cases (8.7 percent) of colorectal primary cancer associated with extracolonic primary malignancy of 14 lesions and 10 cases (6.7 percent) of multiple primary colorectal cancers were included. Among the 14 lesions of extracolonic primary malignancy, there were 6 gastric carcinomas, 2 endometrial carcinomas, 2 urinary bladder carcinomas, and one each in the esophagus, liver, bile duct and jejunum. The second tumor was not detected preoperatively in 3 of 4 cases of synchronous multiple primary colorectal carcinoma. A curative resection was done in 10 (77 percent) out of 13 cases of colorectal cancer associated with extracolonic malignancy, while 7 (88 percent) out of 8 cases of multiple colorectal cancers had a curative resection. Nine patients (69 percent) with colorectal cancer associated with extracolonic malignancy were disease-free for 2 months to 14 years. Seven patients (88 percent) with multiple colorectal cancers were disease-free for one to 22 years. We recommend, therefore, that in any patient with colorectal cancer, the entire large bowel should be thoroughly searched for any other primary tumors, by taking the existence of extracolonic tumors into account. A curative resection should be performed, and the follow-up period should be life-long.