Real-world Prognostic Data on Unresectable Stage III Non-small-cell Lung Cancer Treated with Concurrent Chemoradiation Therapy by Histological Type.

Objective The current standard treatment for locally advanced, unresectable stage III non-small-cell lung cancer (NSCLC) is concurrent chemoradiation therapy (CCRT) and durvalumab administration. Although reports have indicated that the prognosis of squamous cell carcinoma is poorer than that of adenocarcinoma, real-world data are currently inadequate. Methods The present study analyzed patients with stage III NSCLC who received CCRT at the study center between April 2018 and February 2022. These patients were retrospectively classified into adenocarcinoma and squamous cell carcinoma groups for an analysis of the progression-free survival (PFS), overall survival (OS), and patient background factors, including the age, performance status, smoking history, and pre-CCRT laboratory data. Results A total of 109 patients were included for the analysis; 25 were excluded, and 44 and 40 patients were classified into the adenocarcinoma and squamous cell carcinoma groups, respectively. The median PFS was significantly longer in the adenocarcinoma group than in the squamous cell carcinoma group [27.9 (95% confidence interval {CI}: 15.2-not achieved) vs. 9.63 (95% CI: 5.88-13.9) months; p<0.01]. Similarly, the median OS was significantly longer in the adenocarcinoma group than in the squamous cell carcinoma group [not achieved (95% CI: 48.1-not achieved) vs. 23.8 (95% CI; 14.6-not achieved) months; p<0.01]. In the multivariate Cox proportional hazard analysis, the histological type was the only prognostic factor for the PFS (p<0.05) and OS (p<0.05). Conclusion The median PFS and OS were poorer in patients with squamous cell carcinoma than in those with stage III NSCLC treated with CCRT and durvalumab. The histological type was an independent factor affecting the PFS and OS.