Twelve-year experience with two courses of adjuvant single-agent carboplatin therapy for clinical stage I seminoma

During the past 30 years, radiation therapy with 28 to 30 Gy for para-aortic and ipsilateral iliac node areas was the standard adjuvant treatment for clinical stage I seminoma after orchiectomy. However, late effects of radiotherapy prompted a search for alternative adjuvant treatment approaches, including surveillance and application of carboplatin. In this retrospective analysis, we evaluated the efficacy and toxicity of two adjuvant single-agent carboplatin courses in 107 patients who were diagnosed with clinical stage I seminoma at our study centers between 1988 and 1999.

All 107 patients (median age, 39 years; range, 24 to 63 years) received two postoperative adjuvant cycles of carboplatin (400 mg/m(2)). The pathologic tumor stage was pT1 in 84 patients, pT2 in 18 patients, and pT3 in five patients. Whole blood count and serum chemistry were evaluated weekly during treatment to assess hematologic and nonhematologic toxicity.

Six patients died from tumor-unrelated causes. The remaining 101 patients are currently alive and free of disease after a median follow-up of 74 months (range, 5 to 145 months). A detailed analysis of hematologic toxicity showed only World Health Organization (WHO) grade 1 leukocytopenia in 10.7% of all cycles and WHO grade 2 leukocytopenia in 2.1% of all cycles.

Regarding the absence of tumor recurrences in our retrospective analysis and the favorable toxicity profile with no episodes of long-term toxicity, we suggest that two adjuvant courses of single-agent carboplatin for clinical stage I seminoma patients might be equivalent to radiotherapy.