RESUMEN
PURPOSE: The incidence of multiple primary malignant neoplasm has increased in recent decades. The etiologies and epidemiologies of multiple primary malignant neoplasm are still remained to be verified. A group of patients with multiple primary malignant neoplasms accompanied by colorectal cancer was analyzed to determine the relationship between certain cancers and colorectal cancer. MATERIALS AND METHODS: From Jan. 1989 to Jun 1997, there were 56 patients with colorectal cancers accompanied by cancers of another organs. The retrospective analysis was done on the basis of cancer origin and intervals between the cancers. RESULTS: The male-to-female ratio was 25 to 31. The characteristics of colorectal cancers in multiple primary malignant neoplasm were similar to the colorectal cancers without other cancers. Among 56 patients, 50 patients had the double primaries and 6 had the triple primaries. In the patients with double primaries, extracolonic cancers were found in the stomach(16), hepatobiliary system(12), urologic system(6), gynecologic organ(6) and others. In the patients with triple primaries, extracolic cancers were found in the stomach(5), uterus(2), lung(2) and others. The patients with family history of malignancy were 10 cases and the rate in the triple primaries seemed to be higher than double primaries. CONCLUSION: It could be desirable to follow-up and work-up the patients with colorectal cancer keeping in mind that the malignancy in other organs especially stomach might be present.