Retrospective multicentre study of carboplatin monotherapy for clinical stage I seminoma

Study Type – Therapy (prospective cohort) Level of Evidence 2a What’s known on the subject? and What does the study add? The debate concerning standard treatment following unilateral inguinal orchiectomy for patients with clinical stage I seminoma is ongoing. The MRC TE19/EORTC 30982 trial has proven the non-inferiority of carboplatin to radiotherapy, representing a strong argument for the potential use of carboplatin especially with respect to a good long-term side-effect profile. More data and a longer follow-up for carboplatin are required. Different guidelines state that ‘two courses of adjuvant carboplatin seem to further reduce the relapse rate. . . . but further experience and long-term observations are needed’. The present study retrospectively evaluated the long-term oncological efficacy and morbidity of this approach in a multicentre setting to add further long-term data to this topic. OBJECTIVE • To evaluate, in a retrospective multicentre study, the long-term oncological efficacy and morbidity of using carboplatin as an alternative treatment for patients with clinical stage I seminoma. PATIENTS AND METHODS • Patients with clinical stage I seminoma treated with two cycles of adjuvant single-agent carboplatin (400 mg/m2 body surface) from February 1990 until September 2008 were retrospectively identified. • A database was created (including information on patient characteristics, initial tumour staging, tumour marker levels, follow-up, oncological outcome, treatment side effects and long-term side effects), descriptive analyses were performed and the data were compared with those available in the literature. RESULTS • Of 282 stage I seminomas identified in 276 patients, risk factors for progression (pT2/3, vessel invasion or tumour diameter ≥4 cm) were detected in 48.2% of tumours. • Chemotherapy was well tolerated, with patients experiencing only mild nausea. Bone marrow suppression was common (leucopaenia in 36.7% and thrombocytopaenia in 50.5% of patients, mainly grade 1/2). Neither neutropenic fever, nor any bleeding complication occurred. • During a mean follow-up of 75 months, three patients (1.06%) developed a retroperitoneal recurrence within the first 2 years after receiving adjuvant treatment and were salvaged by cisplatin-based chemotherapy. A contralateral second testicular germ cell tumour was diagnosed in five patients. CONCLUSIONS • Two cycles of carboplatin monotherapy are highly effective and very well tolerated by all patients. The frequency of contralateral tumours appears to be reduced. • Despite the lack of a randomized trial, the available data in the literature suggest that the administration of two cycles instead of one cycle could lead to a reduction in recurrence rates of ≈50%.