Second malignancies following pure seminoma

Purpose: Second malignancies in patients with pure testicular seminoma were studied in order to look for adverse late effects of treatment and to stud y the significance of second malignancies during follow-up. Patients, Metho ds: In a multicentric investigation, 839 consecutive patients with pure tes ticular seminoma were observed for a median follow-up of 3.9 years. Thirty- seven patients had been excluded from the study because they already had ha d either a contralateral testicular germ cell tumor or another malignancy. 758 patients received radiotherapy, 76 underwent chemotherapy, 5 had survei llance only. The expected rate of second cancers was calculated according t o the data of the cancer registry of Saarland, Germany. Results: Twenty-two second cancers (13 contralateral testicular tumors, 9 extratesticular mali gnancies) were recorded. The overall risk of having a second cancer was RR = 4.8 (95% CI 3.0-7.3). The risk of having a subsequent testicular tumor is RR = 44.8 (95% CI 23.9-76.7). 1.1% of the patients developed a nontesticul ar second tumor. The risk of having a nontesticular second cancer is RR = 2 .1 (95% CI 1.0-4.0). A significantly increased risk was observed for renal cell cancer as well (RR = 12.5; 95% CI: 1.5-45.1). Increased RR without rea ching statistical significance were found for rectal cancer (RR = 5.0; 95% CI: 0.1-27.9) and non-Hodgkin lymphoma (RR = 6.7; 95% CI 0.2-37.1). None of the second cancers were directly located within the radiation field; 5 neo plasms arose at the border of the radiation field. Conclusions: This study confirmed the increased risk of having a second testicular germ cell cancer . There is also a small but definitely increased overall risk of having a n ontesticular second cancer. Treatment-unrelated factors - possibly genetic predisposition - must be considered for a substantial number of these secon d tumors, since in the present study the follow-up was rather short and mos t of the second cancers were located outside of the radiation fields. In pa rticular, the association of renal cancer with testicular cancer appears to be a more than chance occurrence. Second cancer is a real hazard following treatment of testicular cancers and should always be considered during fol low-up. Copyright (C) 2000 S. Karger AG, Basel.