What is the role of consolidation radiotherapy (RT) in stage 3 seminoma?

Role of Consolidation Radiotherapy in Stage 3 Seminoma

Consolidation radiotherapy is not recommended for stage III seminoma patients, as chemotherapy alone is the standard treatment with patients achieving complete response requiring no further therapy. 1

Standard Treatment Approach for Stage III Seminoma

First-Line Treatment

• Chemotherapy with PEB (cisplatin, etoposide, bleomycin) is the standard treatment for stage III seminoma: three cycles for good prognosis patients and four cycles for intermediate prognosis patients 1
• For patients with contraindications to bleomycin, four cycles of PE (cisplatin, etoposide) can be used as an alternative 1
• For intermediate prognosis patients, four cycles of VIP (etoposide, ifosfamide, cisplatin) with G-CSF support can be considered if bleomycin is contraindicated 1

Post-Chemotherapy Management

• Patients with complete response after chemotherapy do not require further treatment, including consolidation radiotherapy 1
• For patients with residual masses after chemotherapy, management depends on the size of the residual mass:
  • Residual masses <3 cm: follow-up only is recommended without additional therapy 1
  • Residual masses ≥3 cm: FDG-PET scan is recommended at least 6 weeks after completion of chemotherapy 1

Management of Residual Masses

PET-Guided Approach

• If PET scan is negative: follow-up only is recommended without consolidation radiotherapy 1
• If PET scan is positive: surgical resection should be considered rather than consolidation radiotherapy 1

Recent Evidence for Radiotherapy in Residual Masses

• A recent study suggests that radiotherapy might benefit patients with post-chemotherapy residual masses with SUVmax ≥3 on PET-CT 2
• In this study, locoregional failures were 5.8% in the radiotherapy group versus 29.4% in the observation group for high-risk patients (SUVmax ≥3), though this did not translate to overall survival benefit 2
• Despite these findings, current guidelines still do not recommend routine consolidation radiotherapy for stage III seminoma 1

Historical Context

• Historically, radiation therapy was considered for stage III seminoma patients, but this approach has been replaced by chemotherapy as the primary treatment modality 3
• The shift from radiotherapy to chemotherapy occurred due to the excellent response rates and survival outcomes with platinum-based chemotherapy regimens 1

Salvage Treatment Options

• For patients who relapse after complete response to chemotherapy:
  • Standard salvage chemotherapy is recommended 1
  • For small localized relapses, radiotherapy may be considered as part of the salvage strategy 1
  • Surgery should be an integral part of the salvage strategy, particularly for patients with localized or late relapse 1

Follow-up Recommendations

• After complete response to chemotherapy for stage III seminoma:
  • Physical examination and tumor markers: every 2 months in year 1, every 3 months in year 2, every 4 months in year 3, and every 6 months in years 4-5 1
  • Chest X-ray: every 4 months in year 1, every 6 months in year 2, and annually in years 3-5 1
  • CT abdomen/pelvis: as needed until complete response, then according to chest X-ray schedule 1

Conclusion

The current standard of care for stage III seminoma is chemotherapy alone, with no role for routine consolidation radiotherapy. Residual masses should be evaluated with PET-CT if ≥3 cm, with observation recommended for PET-negative residuals. While recent research suggests potential benefit of radiotherapy for specific high-risk residual masses, this approach is not yet incorporated into current guidelines and should be considered only in selected cases at expert centers.