Real-World Treatment Patterns and Outcomes in Patients Receiving Second-Line Therapy for Advanced/Metastatic Esophageal Squamous Cell Carcinoma

Introduction Currently available second-line (2L) therapies for advanced/metastatic esophageal squamous cell carcinoma (adv/met ESCC) include the taxanes paclitaxel and docetaxel. In clinical trials, such therapies have provided only modest improvements in survival. Few studies have assessed outcomes in routine clinical practice in the USA. We compared real-world clinical outcomes in the US for patients receiving taxane or non-taxane 2L therapy for adv/met ESCC. Methods The Flatiron Health database was used to identify patients diagnosed with adv/met ESCC (1 January 2011-31 January 2019) who received 2L therapy; index date was date of adv/met diagnosis. Baseline variables and treatment regimens received were identified. Overall survival (OS; 2L start until death or last recorded medical activity) and duration of therapy (DoT; start of 2L therapy until last administration date of 2L therapy) in patients receiving taxane vs. non-taxane-based therapies in the 2L setting were estimated by Kaplan-Meier method. Results There were no clear differences in baseline characteristics between patients who received 2L taxane therapy (n = 37) and 2L non-taxane therapy (n = 49). Median (95% CI) 2L OS was significantly longer with 2L taxanes (7.3 [5.9-11.5] months) vs. 2L non-taxanes (5.1 [2.9-7.6] months); median (95% CI) 2L DoT was 2.1 (1.8-3.0) months vs. 3.3 (2.6-6.7) months, respectively. Conclusion Survival was generally poor in patients receiving 2L therapy for adv/met ESCC and was longer in patients receiving 2L taxanes than 2L non-taxane therapy. Efficacious, tolerable therapies for ESCC in the 2L setting are urgently needed.