Comparative Evaluation of Concurrent Carboplatin-Paclitaxel Versus Cisplatin-Etoposide Chemoradiotherapy in Unresectable Non-small Cell Lung Cancer: A Prospective Randomized Study

Abstract

Background: Concurrent chemoradiotherapy (CCRT) is the standard treatment for patients with unresectable non-small cell lung cancer (NSCLC). Cisplatin-etoposide (EP) and weekly carboplatin-paclitaxel (PC) are commonly used concurrent regimens, but comparative data on efficacy and toxicity remain limited. This study compared acute treatment-related toxicities and tumor response between these regimens, with six- and 12-month progression-free survival (PFS) and overall survival (OS) evaluated as pre-specified exploratory secondary outcomes. Materials and methods: This prospective randomized study included 34 patients with histologically confirmed unresectable NSCLC treated between April 2021 and June 2022. Patients received either EP (n=16) or PC (n=18) concurrently with definitive radiotherapy (60 Gy in 30 fractions). Acute toxicities and three-month tumor response were evaluated. Kaplan-Meier PFS and OS were estimated separately through six and 12 months in 31 evaluable patients, with horizon-specific log-rank and Cox analyses. Results: EP produced significantly more severe anemia, thrombocytopenia, and esophagitis, whereas pneumonitis was numerically more frequent with PC. The tumor-response distribution favored EP (p=0.029). Six-month PFS was 66.7% with EP and 56.3% with PC (p=0.499), and 12-month PFS was 40.0% and 25.0%, respectively (p=0.206). Six-month OS was 93.3% with EP and 81.3% with PC (p=0.317), and 12-month OS was 80.0% and 56.3%, respectively (p=0.144). Conclusions: EP was associated with a more favorable tumor-response distribution and numerically better one-year PFS and OS than PC, but the survival differences were not statistically significant. These potential efficacy benefits were accompanied by greater hematological and esophageal toxicity.