Health care utilization and costs among HER2-negative, HR-positive, elderly women with metastatic breast cancer in the United States.

e11571 Background: Limited data exist on the cost burden of elderly women with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2) negative metastatic breast cancer (MBC). We therefore assessed this cost burden in a retrospective analysis of the Surveillance, Epidemiology and End Results-Medicare database (2000-2009). Methods: Women aged ≥65 years diagnosed with MBC or early-stage breast cancer who progressed to MBC with HER2 negative, HR positive status were selected. MBC diagnosis date or date of progression to MBC was the index date. The study included non-HMO patients who had continuous Medicare (Part A and B) enrollment for ≥12 months before index date to death or end of database (2009). All-cause and MBC-related (claims for MBC diagnoses or MBC-related treatments) healthcare utilization and costs were assessed descriptively and then annualized based on follow-up duration. Results: In total, 13,170 women met the inclusion criteria (mean [SD] age 76.7 [7.0] years, 88% white, 77% both ER and PR positive). Mean [SD] post-index follow-up duration was 38.5 [28.1] months. On average, patients had 2.5 hospitalizations (mean length-of-stay: 16 days) and 3 emergency department (ED) visits. Mean [SD] annual all-cause costs (in 2011 $) per patient were $34,264 [$33,429], half of which $16,397 [$18,284] were attributable to MBC. Hospitalizations, hospital outpatient visits, and physician office visits accounted for over three-quarters of total all-cause costs (mean [SD]: $13,804 [$22,589] $4,171 [$6,509], and $8,676 [$11,065], respectively) and 75% of MBC-related costs (mean [SD]: $4,449 [$9,436], $2,844 [$5,383], and $5,799 [$9,945], respectively). Within MBC-related costs, mean [SD] annual costs of chemotherapy, radiation, and hormone therapy were $1,442 [$4,095], $1,872 [$4,086], and $579 [$1,197], respectively. Conclusions: Our findings indicate that HR positive, HER2 negative elderly women with MBC have a substantial economic burden on the Medicare system with primary costs drivers being inpatient, hospital outpatient and physician office visit costs.