PURPOSE: Stomach cancer is the most prevalent extracolonic malignancy of the many primary cancers that occur together with colorectal cancer in Koreans. The purpose of this study was to evaluate the characteristics of patients who present with double primary cancer of the stomach and colorectum. METHODS: From Sep. 1994 to Dec. 2004, in 4,305 patients were diagnosed with colorectal cancer. Among these patients, 51 patients were diagnosed synchronously or metachronously as also having stomach cancer. The mean age these patients was 60.8 years and the median follow up duration was 31.0 months. RESULTS: The incidence of double primary cancer of the stomach and colorectum was 1.2% of the total colorecal cancer patients and they were 0.6% of the total stomach cancer patients. There were 17 (33.3%) metachronous cases and 34 (66.7%) synchronous cases. For the metachronous cases, the mean interval was 15 months (12~98) and detection methods were postoperative CT, symptom of second a cancer, and routine endoscopic examination. In synchronous cases, second cancer was detected by routine endoscopic examination, preoperative radiologic evaluation, and intraoperative exploration. Intraoperatively the detected cancers were all colorectal cancer during the operation for stomach cancer. The stage of the colorectal cancer was higher than that of the stomach cancer in 30 cases. Local or systemic recurrences were seen in 9 cases (17.6%), and 7 cases were recurrence of colorectal cancer. The 5-year disease free survival rates was 55.8%. CONCLUSION: The incidence of cancer arising from colorectum and stomach has been reported to be increasing. Careful attention should always be paid to the possible presence of a second cancer in preoperative or postoperative evaluation of cancer patients.
Colonic Neoplasms ; Colorectal Neoplasms ; Disease-Free Survival ; Follow-Up Studies ; Humans ; Incidence ; Neoplasms, Second Primary ; Recurrence ; Stomach Neoplasms ; Stomach*