Radiotherapy timing in the treatment of limited-stage small cell lung cancer: the impact of thoracic and brain irradiation on survival

Aims and background. Small cell lung cancer is an aggressive histologic subtype of lung cancer in which the role of chemotherapy and radiotherapy has been well established in limited-stage disease. We retrospectively reviewed a series of limited-stage small cell lung cancers treated with chemotherapy and thoracic and brain radiotherapy. Methods and study design. A total of 124 patients affected by limited-stage small cell lung cancer has been treated over 10 years in our Institute. Fifty-three patients (42.8%) had concomitant radio-chemotherapy treatment and 71 patients (57.2%) a sequential treatment. Eighty-eight patients (70.9%) underwent an association of a platinum-derived drug (cisplatinum or carboplatinum) and etoposide. Prophylactic cranial irradiation was planned in all patients with histologically proven complete response to primary radio-chemotherapy. Results. With a mean follow-up of 2.2 years, complete response was obtained in 50.8% of cases. We found a significant difference between different radio-chemotherapy association approaches (P = 0.007): percentages of overall survival were respectively 10.0%, 12.9% and 5.6% in early, late concomitant and sequential radio-chemotherapy timing. Cranial prophylaxis did not seem to influence overall survival (P = 0.21) or disease-free survival for local relapse (P = 0.34). Conclusions. Concomitant radio-chemotherapy is the best approach according to our experience. Our results show a benefit of prophylactic cranial irradiation in distant metastasis-free survival.