Therapeutic value of thoracic radiotherapy in elderly patients with extensive-stage small cell lung cancer

Objective: To evaluate the effect of thoracic radiotherapy (TRT) on the prognosis of elderly patients with extensive-stage small cell lung cancer (ES-SCLC). Methods: Clinical data of 83 patients aged ≥ 65 years diagnosed with metastatic ES-SCLC admitted to our hospital from 2010 to 2016 were retrospectively analyzed. All enrolled patients received etoposide plus cisplatin or carboplatin as the standard regimen for chemotherapy. After the propensity score matching (PSM), 70 cases were either assigned into the TRT (n = 35) or non-TRT groups (n = 35). Among them, 56 patients were male and 14 female. The median age was 69 years (range: 65-85 years). The median chemotherapy cycle was 4 cycles (range: 1-11 cycles). The median chest irradiation dose was 50 Gy (range: 30-60 Gy). Overall survival (OS), progression-free survival (PFS) and local recurrence-free survival (LRFS) were regarded as end-point of observation. The survival rate was calculated by using Kaplan-Meier method and statistically compared between two groups by using Log-rank test. Multivariate prognostic analysis was performed using Cox regression model. Results: For all patients, the 1- year OS, PFS and LRFS rates were 40%, 16% and 21%, respectively. Patients undergoing TRT obtained better survival outcomes than their counterparts without TRT: the 1- year OS, PFS and LRFS were 52% vs. 29% (P = 0.005), 30% vs. 3% (P < 0.001), 38% vs. 6% (P < 0.001), respectively. Furthermore, TRT did not increase the incidence of adverse reactions in elderly patients (P = 0.690). Conclusion: The addition of TRT for elder ES-SCLC patients can significantly improve the rate of chest tumor control and prolong the survival time, which is worthy of further validation by prospective studies with large sample size. (authors)