Adjuvant carboplatin treatment for seminoma clinical stage I.

The traditional adjuvant therapy for seminoma stage I is abdominal radiotherapy. Although the relapse rate ranges below 5% this treatment is challenged because concerns about adverse late effects are accumulating. Carboplatin is effective in metastatic seminoma and two pilot studies have indicated effectivity in the adjuvant setting also. As this drug is almost non-toxic in moderate doses it could be an ideal adjuvant treatment for seminoma stage I. A group of 82 patients, mean age 37.5 years (range 22-73 years), with histologically pure seminoma stage I, were given carboplatin 400 mg/m2 after orchiectomy; 60 patients received only one course of carboplatin, and 22 patients received two courses. The median time of observation is 24 months, ranging from 2 to 48 months, and 66 patients have a minimum follow-up of 1 year. There is one relapse so far. Toxicity is rather mild with no severe nausea/emesis. Mean platelet counts were 164/nl after 3 weeks and 208/nl after 4 weeks; thus, myelotoxicity was negligible. Gonadal toxicity was measured by serial follicle-stimulating hormone levels. The mean level was 11.4 U/l before treatment, and 16.2 U/l after 5 weeks, 17.3 U/l after 4 months, 14.5 U/l after 8 months and 13.5 U/l after 12 months. Thus, gonadal toxicity also appeared to be mild. In summary, the efficacies of adjuvant carboplatin and of abdominal radiotherapy seem to be identical. As carboplatin, in the dosage used, involves no severe acute side-effects and probably few late adverse effects, this regimen constitutes a promising new treatment option in seminoma patients stage I that deserves to be studied in randomized trials.