Surveillance in stage I testicular seminoma - risk of late relapse.

Introduction: Surveillance is an alternative to adjuvant radiotherapy for stage I testicular seminoma. We present the long-term results of seminoma surveillance, with emphasis on quantifying the risk of late relapse beyond 5 years.
Methods: From 1981 to 1993, of 431 men with stage I testicular seminoma, 203 were managed by surveillance following radical orchidectomy. The surveillance protocol comprised a combination of clinical examination, CT scans of abdomen and pelvis, chest x-rays and serum markers, at defined intervals.
Results: At a median follow-up of 9.2 years, 35 men have relapsed. Five of the relapses occurred more than 5 years after orchidectomy (at 5.1, 6.9, 7.3, 7.3, and 9.0 years). The actuarial risk of relapse at 5 and 10 years was 15% (standard error [SE] 1.1%) and 18% (SE 1.8%) respectively. One hundred sixty one men were free of relapse at 5 years, and have been followed beyond this point for a median of 4.3 years. The actuarial risk of relapse between 5 and 10 years was 4% (SE 0.5%).
Conclusions: These results demonstrate that there is a small but clinically significant risk of relapse more than 5 years after orchidectomy for stage I seminoma. These data support the need for long term surveillance.