Patients Treated With Platinum-Doublet Chemotherapy for Advanced Non-Small-Cell Lung Cancer Have Inferior Outcomes If Previously Treated With Platinum-based Chemoradiation

We performed a retrospective study of NSCLC patients treated with carboplatin and gemcitabine chemotherapy for either de-novo metastatic disease or recurrent disease after platinum-based chemo-radiation and determined that outcomes are inferior in patients previously exposed to platinum during chemo-radiation. These results suggest that non platinum-based agents or targeted therapies should be considered in this group. Introduction: The standard of care for locoregionally advanced non-small-cell lung cancer is concurrent platinum-based chemoradiation. Many patients relapse, and subsequent systemic treatment may involve platinum-doublet chemotherapy. It is not known if prior platinum-based chemoradiation influences the response to platinum-based chemotherapy given subsequently for relapse. Therefore, we compared outcomes in these patients with those in patients without prior treatment. Methods: A retrospective study of patients who had been treated with carboplatin and gemcitabine chemotherapy for de novo metastatic disease or recurrent non-small-cell lung cancer after receiving platinum-based chemoradiation. The primary outcome was progression-free survival (PFS). Results: A total of 104 patients were analyzed. The median age was 63 years (range, 35-81 years), with 63 (61%) patients with newly diagnosed disease and with 41 (39%) who were previously treated. The response rate was significantly lower for those previously exposed to chemoradiation (10% vs. 29%: P=.001), as was the median PFS (3.6 months vs. 5.7 months; P=.002), and median overall survival (OS) (8.6 months vs. 12.1 months; P=.007). Only the treatment group was a significant predictor (P=.032) of PFS by univariate analysis. In univariate analysis; sex (men; P=.04), histology (squamous cell; P=.04), Eastern Cooperative Oncology Group Performance Status Scale (P=.002), and treatment group (P=.023) predicted significantly inferior OS. Multivariate analysis showed that performance status was the only significant predictor of inferior OS. Conclusion: Outcomes were inferior in patients previously exposed to platinum-based chemoradiation. An approach of stratifying such patients in future trials of chemotherapy should be adopted. Alternative options such as non-platinum-based agents or targeted therapies should be considered in this group.