Omission of the pelvic irradiation in stage I testicular seminoma: a study of postorchiectomy paraaortic radiotherapy.

PURPOSE: To review the survival, cure rate, and pattern of relapse or progression of patients with histologically confirmed Stage I testicular seminoma who underwent orchiectomy and radiation therapy to paraaortic lymphatics only. The pelvic ipsilateral lymph nodes were not irradiated. METHODS AND MATERIALS: Between 1978 and 1992, 150 patients with Stages I or II testicular seminoma received treatment at the Department of Radiation Oncology of the University of Wuerzburg. The distribution by stage was Stage I, 117 patients of which 93 were pT1 N0 M0 and 24 were pT2 N0 M0. Four patients were staged as Stage II (pT3 N0 M0), and in 29 patients the T Stage was not specified. Eighty-six patients from the 117 Stage I (pT1-pT2, N0 M0 according to the TNM classification) seminoma received postorchiectomy irradiation, and are analyzed for outcome in this article. The distribution of the Stage I patients by pT Stage was 71 pT1 and 15 pT2 patients. All these 86 patients had their paraaortic nodes (the biological target volume extending from top of L1 to the bottom of L5) irradiated with four field technique. Tumor dose was specified at normalization point along the central axis. The median tumor dose was 30 Gy given in 1.8-2.0 Gy fractions. Elective irradiation to the ipsilateral hemipelvis (iliac nodes) was totally abandoned. RESULTS: The 10-year disease-free survival and overall survival were 95.3 and 100%. No recurrence in the irradiated field was noted. Four patients (4.7%) experienced relapse of disease outside the treated volume. The most common site of solitary failure was the ipsilateral hemipelvis (one iliacal and one inguinal). One patient developed metastatic disease to the lung. One patient developed a mediastinal recurrence with superior vena cava syndrome and was successfully salvaged by mediastinal irradiation and chemotherapy. CONCLUSIONS: Recommendation for the future management of Stage I seminoma include: reduced biological target volume to the paraaortal lymph nodes (from lumbar vertebra L1 to L5). Complete elimination of irradiation to the pelvic nodes is warranted. Radiation dose should not exceed 30 Gy.