Comparison of efficacy of different fractionation schedules in radiotherapy for extensive-stage small cell lung cancer / 中华放射肿瘤学杂志

ABSTRACT

Objective To evaluate the correlation of different fractionation schedules in radiotherapy with the local control ( LC) and overall survival ( OS) rates in patients with extensive?stage small cell lung cancer ( ES?SCLC ) , and to figure out the relationship between different fractionation schedules in radiotherapy and the prognosis of ES?SCLC. Methods One hundred and ten patients newly diagnosed with ES?SCLC from February 2010 to March 2015 received chemoradiotherapy. According to the radiation dose, all patients were divided into hypo?fractionation group ( 30?45 Gy/3 Gy/10?15 f, n=31) and conventional fractionation group ( 54?60 Gy/1?8?2?0 Gy/27?30 f, n=79) . In all patients, 90?9% had stageⅣSCLC;21 patients had brain metastasis;39 patients were treated with prophylactic cranial irradiation ( PCI ) . The Kaplan?Meier method was used to calculate the survival time and log?rank test was used for between?group comparison. Between?group comparison of categorical data was made by χ2 test. Results The number of patients followed?up were 85 at 2?years. In all patients, the 2?year OS, progression?free survival ( PFS) , and LC rates were 27?7%, 17?5%, and 38?9%, respectively. The hypo?fractionation group had similar prognosis to the conventional fractionation group. There were no significant differences in the 2?year OS, PFS, and LC rates between the two groups ( 35% vs. 26%, P=0?886;18% vs. 16%, P=0?560;67% vs. 36%, P=0?159) . There was also no significant difference in the 2?year OS rate between patients treated with and without PCI (44% vs. 18%, P=0?044). In 84 patients with treatment failure, 11 had local recurrence, 41 had distant metastasis, and 32 had local recurrence plus distant metastasis. Conclusions The hypofractionated radiotherapy has similar efficacy but substantially shortened radiation time compared with conventionally fractionated radiotherapy. The palliative hypofractionated radiotherapy requires further study for ES?SCLC.