Background
Phase III randomized non-inferiority trial (MRC TE19/EORTC 30982). 1,477 patients with stage I seminoma after orchidectomy randomized to adjuvant single-dose carboplatin (AUC 7) vs radiotherapy (20 Gy para-aortic ± ipsilateral iliac). Designed to establish carboplatin as a less toxic alternative to RT. Initial results in Lancet 2005; this JCO 2011 report provides extended follow-up with contralateral testicular GCT data.
Interventions and follow up
Arm A: Carboplatin single dose AUC 7 IV (n=573)
Arm B: Radiotherapy 20 Gy in 10 fractions to para-aortic ± ipsilateral iliac nodes (n=904)
Primary endpoint: Relapse-free survival (non-inferiority)
Median follow up: ~6.5 years (extended follow-up analysis)
Arm B: Radiotherapy 20 Gy in 10 fractions to para-aortic ± ipsilateral iliac nodes (n=904)
Primary endpoint: Relapse-free survival (non-inferiority)
Median follow up: ~6.5 years (extended follow-up analysis)
Results
5-yr relapse-free survival: 94.7% (carboplatin) vs 96.0% (RT) — non-inferiority met (upper CI bound <3%)
Contralateral testicular GCT: Lower with carboplatin (2 cases) vs RT (15 cases), P=.03
Late relapse (after 5 years): More frequent with carboplatin, justifying extended surveillance after carboplatin
Contralateral testicular GCT: Lower with carboplatin (2 cases) vs RT (15 cases), P=.03
Late relapse (after 5 years): More frequent with carboplatin, justifying extended surveillance after carboplatin
Adverse events
Carboplatin: Less nausea and fewer radiation-associated bowel/gonadal effects; no long-term myelosuppression; lower contralateral testicular cancer risk
Radiotherapy: More acute GI symptoms and higher metachronous contralateral testicular tumor risk
Radiotherapy: More acute GI symptoms and higher metachronous contralateral testicular tumor risk
Conclusions
Single-dose carboplatin is non-inferior to radiotherapy for stage I seminoma relapse-free survival and is associated with significantly fewer metachronous contralateral testicular tumors. Carboplatin is an established adjuvant alternative to RT for stage I seminoma.
Key Limitations
Subsequent analyses suggest two cycles of carboplatin (AUC 7 ×2) achieve lower relapse rates than the single dose used here, raising dosing questions. Late relapses with carboplatin occur beyond 5 years, requiring longer surveillance than typical RT follow-up. No direct comparison with active surveillance was performed.
Clinical Context
MRC TE19/EORTC 30982 established single-dose carboplatin as a standard adjuvant option for stage I seminoma, reflected in EAU and ESMO guidance. Two-dose carboplatin (AUC 7 ×2) is now often preferred for superior relapse prevention, though active surveillance remains the preferred approach for compliant patients in most guidelines.