Objectives: To evaluate the long-term oncologic efficacy and morbidity of carboplatin monotherapy, which was introduced at our department 11 years ago for the treatment of Stage I seminoma. Radiotherapy is the standard treatment of patients with clinical Stage I seminoma. Carboplatin has been advocated as a treatment alternative to avoid the late side effects of radiotherapy and the high recurrence rate of surveillance strategies.
Methods: From February 1990 until August 2001, 108 patients received two adjuvant cycles of single-agent carboplatin (400 mg/m2 body surface on days 1 and 22) 2 weeks after high inguinal orchiectomy. To assess for myelosuppression, complete blood counts were performed at least once a week until the nadir occurred after the second treatment cycle.
Results: During a mean follow-up period of 59.8 months (range 6 to 134), 2 patients (1.85%) developed a recurrence (retroperitoneal tumor) within the first year. Both patients received cisplatin-based salvage chemotherapy. At last follow-up, all patients were alive without any evidence of disease. Carboplatin treatment was well tolerated by all patients and was associated with only mild gastrointestinal side effects. Leukopenia was noted in 32 patients (29.6%); 21 (19.4%) of these patients had World Health Organization (WHO) grade 1, 8 (7.4%) had grade 2, 3 (2.8%) had grade 3, and none had grade 4. No patient developed neutropenic fever. Thrombocytopenia was observed in 48 patients (44.4%); of these patients, 38 (35.2%) had WHO grade 1, 5 (4.6%) had grade 2, 2 (1.9%) had grade 3, and 3 (2.8%) had grade 4.
Conclusions: From an oncologic standpoint, two cycles of carboplatin monotherapy was highly effective and very well tolerated by all patients.