The value of postoperative radiotherapy in renal cell carcinoma: a single-institution experience.

Aim: To evaluate the efficacy of postoperative irradiation in renal cell carcinoma. Patients and methods: Forty patients with localized renal cell carcinoma admitted to our hospital between 1986 and 1999 were evaluated. All patients were initially treated with radical nephrectomy. Postoperative radiotherapy was given to 26 of 40 patients (65%). Fourteen patients (35%) received no adjuvant therapy. Median age was 55 years (range, 20-70 years). Twenty-four patients (60%) were men and 16 patients (40%) were women. Histopathological diagnosis was renal cell carcinoma in all of the patients. N+ disease was present in 3 patients (7%). Stage I and II disease was present in 25 patients (63%) and stage III and IV disease in 15 patients (37%). Two patients (5%) had T1a disease, 11 patients (27%) had T1b, 15 patients (38%) had T2, 11 patients (27%) had T3a and 1 (3%) patient had T3b. In the radiotherapy group, renal bed and regional lymphatic fields were irradiated with daily fractions of 180-200 cGy/fraction to a total dose of 46-50 Gy, using parallel opposing fields. Results: The 5-year overall survival rates were 70% in the postoperative radiotherapy group and 20% in the no adjuvant treatment group, showing no significant difference (P = 0.1). The 5-year disease-free survival rates were 66% in the radiotherapy group and 16% in the no treatment group, with a significant difference in both univariate and multivariate analyses (P = 0.045 and P = 0.0007, respectively). Stage III and IV disease, tumor size ≥7 cm, presence of distant metastasis and lactate dehydrogenase level >450 U/L were found to be adverse prognostic factors for overall survival in both univariate and multivariate analyses. Analyzing the factors affecting disease-free survival, absence of postoperative radiotherapy and tumor size ≥7 cm were found to be adverse prognostic factors in univariate and multivariate analyses. Conclusion: Multi-institutional prospective randomized trials using modern radiotherapy techniques such as conformal radiotherapy and intensity-modulated radiotherapy are necessary to evaluate the real role of radiotherapy and its effect on survival in renal cell carcinoma, especially in selected patients with a high risk of local or regional failure.