Assessing direct costs of treating metastatic triple-negative breast cancer in the USA.

Evaluation of monthly cost during metastatic triple-negative breast cancer (mTNBC) treatment. Retrospective electronic medical record review of US females aged ≥18 years diagnosed with mTNBC between 1 January 2010 and 31 January 2016. Mean monthly costs per patient were evaluated from start of mTNBC treatment until transfer to hospice, end of record or 3 months prior to death. The mean monthly cost of first line was $21,908 for 505 treated patients; 50.2% of cost was attributable to hospitalization and emergency department visits, and 32.7% to anticancer therapy. Similar patterns were observed for subsequent lines of therapy. The majority of costs were attributable to hospitalization and emergency department services, suggesting a need for effective interventions to reduce utilization of costly services.