Efficacy of synchronous stereotactic radiotherapy with temozolomide combined with whole brain radiotherapy in treating brain metastases originating from non-small cell lung cancer.

PURPOSE To investigate the efficacy and safety of synchronous stereotactic radiotherapy (SRT) with temozolomide (TMZ) combined with whole brain radiotherapy (WBRT) in treating brain metastases originating from non-small cell lung cancer (NSCLC). METHODS The clinical data of 128 patients with brain metastases originating from NSCLC treated in the hospital from August 2015 to August 2017 were retrospectively analyzed. Among these patients, 64 received synchronous SRT with TMZ+WBRT (TMZ group), and 64 underwent SRT+WBRT (radiotherapy group). The clinical data of all patients were collected, and the short-term responses and adverse reactions after treatment were compared between the two groups. Additionally, the patients were followed up to record the overall survival (OS) and progression-free survival (PFS), and the factors probably affecting the prognosis of patients were analyzed. RESULTS The incidence rate of nausea & vomiting was overtly higher in the TMZ group than that in the radiotherapy group (67.2% vs. 43.8%, p=0.008), while the incidence rate of other treatment-related adverse reactions showed no remarkable difference between the two groups (p>0.05). The follow-up results revealed that the median OS and PFS were (13.1±4.6) and (11.2±4.2) months in the TMZ group and (10.6±3.8) and (8.3±3.4) months in the radiotherapy group, respectively. According to log-rank test, the OS and PFS of patients in the TMZ group were evidently better than those in the radiotherapy group (p=0.041, p=0.025). Univariate and multivariate regression analyses suggested that the absence of extracranial metastasis, recursive partitioning analysis (RPA) class I, mini mental status examination (MMSE) score ≥27 points before radiotherapy, and treatment with TMZ were protective factors affecting the prognosis of patients. CONCLUSIONS Synchronous SRT with TMZ combined with WBRT is effective in treating patients with brain metastases originating from NSCLC, which can effectively improve the survival of patients and has tolerable adverse reactions. The absence of extracranial metastases, RPA class I, MMSE score ≥27 points before radiotherapy and treatment with TMZ are protective factors affecting the prognosis of patients.