Background: Radiotherapy is accepted as standard adjuvant treatment for low-stage seminoma and results in excellent survival rates. The optimal radiation field for stage I seminoma, however, is still being discussed.
Patients and methods: In a retrospective study we evaluated long-term results concerning survival, relapse-pattern, and acute and chronic toxicity in patients receiving adjuvant radiotherapy of the paraaortic and ipsilateral iliac lymph nodes (hockey-stick, HS) versus radiotherapy of the paraaortic lymph nodes only (PA). From 1979-1997, 129 patients (median age 32 years) in clinical stage I received adjuvant radiotherapy. Eighty-seven patients were treated with 36 Gy to the HS field and 42 patients were treated with a median of 28 Gy to the PA field.
Results: With a median follow-up of 7.7 years (HS) and 5.2 years (PA) the relapse rate was 3.4% and 2.4%, respectively. There was no abdominal or pelvic recurrence in either group. Radiotherapy was well tolerated in both groups. No significant difference in acute or chronic toxicity was noted. However, lower gastrointestinal tract toxicities and myelotoxicities appeared less frequent in the PA group. Second malignancies only occurred in the HS group. Overall survival in the HS and PA group was 96.6% and 100%, respectively. No patient died of seminoma.
Conclusion: With paraaortic radiotherapy only, long-term disease-specific survival was excellent. Decreased risk of acute toxicity and of second malignancies are potential benefits of the reduced radiation field.