Characteristics of multiple primary malignancies in renal cell carcinoma

Purpose: This study aimed to evaluate the incidence, nature and prognosis of multiple primary malignancies in renal cell carcinoma. Materials and methods: From June 1995 to April 2004, we retrospectively reviewed the records of 578 patients who underwent an operation for renal cell carcinoma at Yonsei University. The incidence of other primary malignancies, in addition to the renal cell carcinoma, was determined and classified as antecedent, synchronous or metachronous. We analyzed the influence of the other primary malignancies on the prognosis, and the overall survival rates of the patients with multiple primary malignancies were compared to the remaining patients. Results: Of the 578 patients, 62 patients (10.7%) had at least one malignancy beside renal cell carcinoma. In these cases, renal cell carcinoma was commonly incidental, small or low stage (75.8%). 22 patients (35.4%) had gastrointestinal cancer and 11 patients (17.7%) had hepatobiliary cancer. The malignancies were antecedent in 25 (40.3%), synchronous in 24 (38.1%), and metachronous in 14 patients (22.2%). On the analysis of overall survival with using the log rank test, there was no statistically significant factor for the presence of other antecedent or synchronous malignancies. Conclusions: Primary malignancy associated with renal cell carcinoma in the Korean population shows a different pattern from that of Western countries. The expected survival rate of patients suffering from renal cell carcinoma with tumor involvement of other organs, if surgically treated, is similar to that of renal cell carcinoma alone, so aggressive surgical treatment of renal cell carcinoma should be performed.