Clinical outcomes of stage IIA/IIB seminoma treated with radiotherapy and chemotherapy: should regional therapy be considered the preferred treatment approach?

Purpose: The optimal management of patients with de novo clinical stage IIA/B (CSIIA/B) or relapsed CSIIA/B (Rel-CSIIA/B) seminoma remains debated due to a lack of randomized evidence. Herein, we sought to evaluate outcomes following radiotherapy and chemotherapy in this setting.

Materials and methods: A prospectively maintained single-institutional database was retrospectively queried for patients diagnosed between 1995-2016 with de novo or Rel-CSIIA/B. Patients with Rel-CSIIA/B were managed similarly to de novo CSIIA/B. All patients were reviewed by the multidisciplinary team. While the preferred management policy was radiotherapy, the treatment decision was individualized at the physician/patient level.

Results: There were 153 patients: 67 had de novo CSIIA/B (IIA-32, IIB-35) and 86 patients had Rel-CSIIA/B seminoma (IIA-51, IIB-35). Of the total, 120 patients (78%) received radiotherapy (IIA-78, IIB-42) and 33 (22%) received platinum-based chemotherapy (IIA-5, IIB-28). Median follow-up was 7.1 years (IQR 4.3-9.9). Eleven patients (IIA- 9/78, IIB- 2/42) relapsed following radiotherapy and 1 patient (IIB) relapsed following chemotherapy, corresponding to 5-year relapse rates of 10% (95% CI 6-18%) for radiotherapy and 3% (95% CI 0-23%) for chemotherapy. All 12 patients who relapsed were treated with subsequent chemotherapy.

Conclusion: Radiotherapy and chemotherapy result in excellent oncologic outcomes for patients with de novo or Rel-CSIIA/B seminoma. All patients should be informed about both management options. However, radiotherapy with its favourable acute toxicity profile, could be considered the treatment of choice in most patients.