The initiation of radiotherapy (RT) 2 months or longer after induction chemotherapy vs initiation within 2 months of induction chemotherapy was found to be associated with shorter disease-free survival (DFS), but not overall survival (OS), among patients with locally advanced non-small cell lung cancer (NSCLC).1 These findings from a retrospective study were presented at the 2020 World Conference on Lung Cancer in Singapore.
Although concurrent RT and chemotherapy has demonstrated superior outcomes compared with sequential administration or chemotherapy alone for locally advanced NSCLC, more than 50% of patients are considered ineligible for concurrent regimens. The aim of this study was to evaluate the effect of timing of sequential RT after chemotherapy on the outcomes of patients with locally advanced NSCLC.
The retrospective study included data from 80 patients with stage 3 NSCLC who received definitive RT between 2010 and 2015. The majority (71%) of patients received RT after induction chemotherapy, 15% received RT concurrent with chemotherapy, and 13.7% received RT only. The chemotherapy regimens were platinum-based doublets, with a median of 4 cycles (range, 3-6). The median dose of RT administered was 60 Gy.
The researchers found that 2-year DFS was significantly shorter among patients who underwent initiation of RT more than 2 months after chemotherapy compared with patients who began RT within 2 months after chemotherapy (11% vs 25%; P =.0013). Outcomes related to OS were similar, with 2-year rates of 19% and 26% among patients who received RT after or within 2 months of chemotherapy, respectively.
Patients who received concurrent RT and chemotherapy had similar DFS as patients who received sequential RT, but OS was found to be significantly longer with concurrent treatment (P=.009). The worst outcomes were reported in patients who received RT alone, according to the investigators.
The authors concluded that the findings “suggest that DFS may be significantly inferior in patients with locally advanced NSCLC who undergo definitive RT later than 2 months after induction chemotherapy.” They added that the timing of RT did not affect OS.
Scepanovic D, Dzongov M, Hanicova M, et al. Impact of radiotherapy timing after induction chemotherapy on survival of patients with locally advanced non small cell lung cancer. Presented at: 2020 World Conference on Lung Cancer Singapore; January 28-31, 2020.