BACKGROUND: Hormone receptor positive (HR+)/HER2– tumors are the most common subtype among patients with metastatic breast cancer (MBC). Several newer therapeutic options have become available over the last decade, but little is known about the real-world treatment patterns and health care resource use (HCRU) in privately insured women with HR+/HER2– MBC.
METHODS: An analysis of Truven MarketScan databases containing medical and drug utilization and productivity data from nearly 350 United States payers was conducted. Patients aged 18-64 years with an ICD-9 diagnosis code of breast cancer along with ≥2 claims for secondary malignancy between 2007 and 2013 were selected. HR+/HER2– patients were identified based on receipt of endocrine therapy (ET) and absence of HER2-targeted therapies. Use of cancer-directed treatments following MBC diagnosis was analyzed. Treatment characteristics were examined by line of therapy (LOT). Average monthly all-cause and MBC-related HCRU were descriptively assessed.
RESULTS: A total of 5,563 women with HR+/HER2– MBC (mean [SD] age, 54 [7.8] yrs) met the selection criteria. Overall, 97% of the total sample received ≥1 cancer-directed treatment. The most common treatment was ET (85%), followed by chemotherapy (CT) (70%), radiation (62%), and surgery (11%). Treatment patterns for CT alone and ET alone, including the top regimens by LOT, are presented in Table 1. Among those receiving a second LOT, nearly 44% switched to CT in the second line after having received ET alone in the first line. During the study follow-up, 56% of patients had ≥1 all-cause inpatient admission, 49% had ≥1 all-cause emergency department visit, and 9% had a hospice admission.
CONCLUSIONS: A substantial decrease in the use of ET, with simultaneous increase in the use of CT, was observed as patients progressed to subsequent LOTs. Nearly half of those receiving ET alone in the first LOT switched to CT in the second LOT, suggesting a need for more effective non-CT treatments to bridge unmet therapeutic needs in this patient population.
