Survival Outcomes of Metastatic Non-small Cell Lung Cancer Patients With Limited Access to Immunotherapy and Targeted Therapy in a Cancer Center of a Low- and Middle-Income Country.

Abstract

To describe the survival outcomes of metastatic non-small cell lung cancer patients with limited access to immunotherapy and targeted therapy in a cancer reference center in Colombia. A retrospective analysis of metastatic non-small cell lung cancer patients treated between 2013 and 2018 was performed, majority diagnosed with adenocarcinoma. It was carried out in a public cancer reference center that provides care to patients of low and middle socioeconomic status. Overall survival and progression-free survival were evaluated by Kaplan-Meier analysis and log-rank test. A Cox regression model was performed for univariate and multivariate analysis. 209 patients were included with majority of adenocarcinoma (79.5%). First-line treatment was cytotoxic chemotherapy (50.2%), EGFR-targeted therapy (14.8%), chemoimmunotherapy (1.9%), and ALK-targeted therapy (1.4%). 31.6% received best supportive care. Median time of follow-up was 13 months, median overall survival was 11.2 months (95% CI, 7.9-14.4), 13 months for adenocarcinoma (95% CI, 8.1-17.9), and 2.5 months for squamous cell carcinoma (95% CI, 0.6-4.4) (P < .001). Median progression-free survival was 9.3 months (95% CI, 7.9-10.7) without differences according to the type of first-line therapy. Median time-to-treatment was 55 days and only 54% of patients with a tested actionable mutation in EGFR received an EGFR-targeted therapy as the first-line treatment. Multivariate analysis showed that squamous cell carcinoma histology and receiving best supportive care were independent factors for worse overall survival ((HR:1.8, 95% CI, 1.076-3.082, P=.026) and (HR:14.6, 95% CI, 8.921-24.049, P < .001), respectively). Meanwhile, squamous cell carcinoma histology was an independent factor for worse progression-free survival (HR:3.4, 95% CI, 1.540-7.464, P=.002). Despite advances in precision medicine, during the study period, cytotoxic chemotherapy was the most used treatment in our patients. Furthermore, about a third of them received best supportive care. The use of targeted therapies has been restricted by access to molecular diagnosis and remained low until 2018. Access to immunotherapy should be prioritized.