Irradiation of brain metastases from lung cancer: a retrospective study

A total of 94 patients with brain metastases from lung carcinomas were treated with irradiation of their brain metastases. Two fractionation schedules were applied, a non-conventional one (76 patients) mixing hypofractionation and accelerated hyperfractionation to a total dose of 47 Gy and a conventional one (18 patients), with 3 Gy once a day to a total dose of 30 or 36 Gy. No benefit was found for the non-conventional treatment schedule over the conventional one. A difference in survival was demonstrated between patients whose brain metastases originated from adenocarcinoma or squamous cell carcinoma of the lung with a median survival of 3.5 and 1.9 months, respectively (P = 0.006). Median survival of patients with brain metastases from small cell lung cancer (SCLC) was 2.8 months, and when compared with the squamous cell carcinoma group, there was no statistically improved survival (P = 0.12). There were indications of a better palliative effect in adenocarcinomas compared with squamous or large cell carcinomas. In a few patients (1/22 adenocarcinoma and 7/32 SCLC), the patients were free from malignant cells in the brain at autopsy, demonstrating that irradiation of brain metastases might be efficient in certain patients.