Abstract P1-16-04: First-line chemotherapy for breast cancer patients by site of care (SOC): Treatment patterns, cost and quality indicators
Authors: Masaquel A , Hopson S , Casebeer A , Drzayich-Jankus D , Tao Z , Stemkowski S , Howe A , Patton J , Small A , Barnett B 
Published: May 2016

Background: Previous studies found differences in treatment patterns and costs by SOC for first-line chemotherapy treatment for both early stage and metastatic breast cancer (esBC and mBC) in commercial populations. This study extends the research to a predominantly Medicare population comparing chemotherapy treatment patterns, cost and quality of care in physician office (PO) and hospital outpatient (HO) centers.

Methods: First-line chemotherapy or biologic therapy for esBC and mBC patients was compared by SOC. Patients initiating infusion therapy in 2008–2012 were identified in Humana medical claims data. First-line length of therapy (LOT) in days and number of infusions (NI) were calculated. SOC cohort (HO vs PO) was based on where the patient received ≥90% of their infusions. Total healthcare costs based on medical and pharmacy claims were assessed. Differences in quality indicators, use of infusions or hospitalizations 30 days prior to death were evaluated. SOC differences were assessed using X2, T-tests and Wilcoxon Rank Sum (Wil) tests. P-values are for X2 and Wil tests. Cost-related results are from generalized linear models adjusted for age, sex, comorbidity and geographic region. LOT and NI are presented as median (IQR).

Results: A total of 2,784 esBC patients (73% PO and 27% HO) and 1,602 mBC patients (64% PO and 36% HO) were identified. Most patients (67%) were Medicare beneficiaries. Mean comorbidity index was similar by SOC for esBC patients (PO 4.2, HO 4.1, p=0.3308) but higher in HO for mBC patients (PO 7.5, HO 7.9, p=0.0003). LOT in days for esBC was greater in the PO for anthracycline-based therapy, PO 64(43-72), HO 47(43-64), p=0.0420 and taxane-based therapy, PO 64(64-106), HO 64(64-76), p=0.0005. NI for esBC was greater in the PO for patients on biologic and cytotoxic therapy, PO 21(17-29), HO 18(16-25), p=0.038 and taxane–based therapy PO 4(4-6), HO 4(4-4), p=0.0005.

No difference in LOT by SOC was seen for mBC patients; however, patients on taxane-based therapy had a greater NI at the PO 6(4-12) vs HO 5.5(4-9), p=0.0225.

Total healthcare costs were higher in the HO vs PO setting for esBC and mBC patients. Costs were 22% higher in the HO $51,191 vs PO $41,943, p&lt;0.0001 for esBC patients and 17% higher in the HO $58,105 vs PO $49,591, p&lt;0.0001 for mBC patients.

There were no statistically significant differences in use of infusions or hospitalizations 30 days prior to death among Medicare patients. Among 223 esBC and 369 mBC Medicare patients who died, use of infusions prior to death was 24% for HO and 16% for PO among esBC, p=0.2357 and 23% for HO and 26% for PO among mBC, p=0.5319. Hospitalizations prior to death were 59% for HO and 59% for PO for esBC, p=0.9940 and 60% for HO and 55% for PO for mBC, p=0.3105.

Conclusion: Differences by site of care, particularly in healthcare costs, were found in a mostly Medicare population of esBC and mBC patients. Patients in the HO setting had shorter length of therapy and fewer infusions, but had higher total healthcare costs than those in the PO setting. Quality indicators, infusions and hospitalizations prior to death were similar by site of care. Future research will focus on other quality indicators and patient satisfaction.

Citation Format: Masaquel A, Hopson S, Casebeer A, Drzayich-Jankus D, Tao Z, Stemkowski S, Howe A, Patton J, Small A, Barnett B. First-line chemotherapy for breast cancer patients by site of care (SOC): Treatment patterns, cost and quality indicators. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-16-04.