Does histology predict survival of advanced non-small cell lung cancer patients treated with platin-based chemotherapy? An analysis of the Eastern Cooperative Oncology Group Study E1594

Introduction: We conducted this analysis to determine whether survival of advanced NSCLC patients treated with platin-based chemotherapy doublets involving paclitaxel, docetaxel or gemcitabine was dependent on histological subtypes and treatment regimen. Methods: We retrospectively analyzed data from E1594, a front-line phase III study in which advanced NSCLC patients were randomized to receive one of four regimens: cisplatin-paclitaxel, cisplatin-gemcitabine, cisplatin-docetaxel, and carboplatin-paclitaxel. Patients were classified into four histology groups: squamous cell (SCC), adeno- (AC), large cell (LCC) and others including not otherwise specified (O/NOS) carcinoma. Logrank test was performed to compare overall survival (OS) and progression free survival (PFS) distributions according to histology as well as treatment. Results: Of 1139 patients including 716 men and 423 women, AC was the most common subtype (56.8%), followed by SCC (19.7%), O/NOS (17.0%) and LCC (6.5%). Men were more likely to have SCC and women were more likely to have AC (p= 0.002). Among the four histology groups, there was no imbalance in regard to race, performance status, weight loss, brain metastasis or treatment. In each histology group, we found no significant difference in OS and PFS between the four chemotherapy regimens. Conversely, in each treatment arm, the survival outcome was similar between the four histology subtypes. Conclusions: Our analysis suggests that histology does not predict survival benefit in advanced NSCLC patients treated with first-line platin-based doublets involving paclitaxel, docetaxel or gemcitabine.