Current status and progress of concurrent chemoradiotherapy in patients with locally advanced non-small cell lung cancer prior to the approval of durvalumab

Background The standard treatment for patients with unresectable locally advanced (LA) non-small cell lung cancer (NSCLC) is chemoradiotherapy (CRT). Consolidation therapy with durvalumab after CRT demonstrated survival benefits and was approved in Japan in July 2018. The use of immune checkpoint inhibitors (ICIs) is entering routine oncological practice, and here we investigate the feasibility of concurrent CRT for LA-NSCLC patients based on the PACIFIC criteria. Methods We performed a retrospective study to evaluate the feasibility and efficacy of concurrent CRT prior to the approval of durvalumab. We assessed consecutive patients with LA-NSCLC treated with CRT between January 2012 and June 2018. Results We analyzed a total of 108 consecutive patients who received radical thoracic radiotherapy and concurrent platinum-based chemotherapy. Of those patients, 105 (97%) completed the planned radiotherapy. Radiation pneumonitis was observed in 93 patients (85%), with a median of 130 days (range: 41-317 days) from the initiation of radiation to the onset of the complication. Among the patients, 74 (69%) were considered eligible for consolidation therapy with durvalumab. The overall response rate was 64%, and the two-year survival rate was 63%. Patients who received an ICI after relapse were associated with significantly better survival than those who did not receive an ICI (two-year survival rate: 87% vs. 41%, respectively; P = 0.001). Conclusions Prior to the approval of durvalumab, the clinical application of ICIs improved the outcome of patients with relapsed NSCLC after CRT for LA-NSCLC. The management of radiation pneumonitis remains a challenge following the approval of durvalumab.