Income disparities in needle biopsy patients prior to breast cancer surgery across physician peer groups.

OBJECTIVE: Evaluate income disparities in receipt of needle biopsy among Medicare beneficiaries and describe the magnitude of this variation across physician peer groups. METHODS: The Surveillance, Epidemiology and End Results (SEER)-Medicare database was queried from 2007-2009. Physician peer groups were constructed. The magnitude of income disparities and the patient-level and physician peer group-level effects were assessed. RESULTS: Among 9770 patients, 65.4% received needle biopsy. Patients with low income (median area-level household income < $33K) were less likely to receive needle biopsy (58.5%) compared to patients with high income (≥ $50K) (68.6%; adjusted odds ratio 0.77; 95% confidence interval (CI) 0.65-0.91). Needle biopsy varied substantially across physician peer groups (interquartile range 43.4-81.9%). The magnitude of the disparity ranged from an odds ratio (OR) of 0.50 (95% CI 0.23-1.07) for low vs. high income patients to 1.27 (95% CI 0.60-2.68). The effect of being treated by a physician peer group that treated mostly low-income patients on receipt of needle biopsy was nearly three times the effect of being a low-income patient. CONCLUSIONS: Needle biopsy continues to be underused and disparities by income exist. The magnitude of this disparity varies substantially across physician peer groups, suggesting that further work is needed to improve quality and reduce inequities.

Surgeon peer network characteristics and adoption of new imaging techniques in breast cancer: A study of perioperative MRI.

BACKGROUND: Perioperative MRI has disseminated into breast cancer practice despite equivocal evidence. We used a novel social network approach to assess the relationship between the characteristics of surgeons' patient-sharing networks and subsequent use of MRI. METHODS: We identified a cohort of female patients with stage 0-III breast cancer from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. We used claims data from these patients and non-cancer patients from the 5% Medicare sample to identify peer groups of physicians who shared patients during 2004-2006 (T1). We used a multivariable hierarchical model to identify peer group characteristics associated with uptake of MRI in T2 (2007-2009) by surgeons who had not used MRI in T1. RESULTS: Our T1 sample included 15 149 patients with breast cancer, treated by 2439 surgeons in 390 physician groups. During T1, 9.1% of patients received an MRI; the use of MRI varied from 0% to 100% (IQR 0%, 8.5%) across peer groups. After adjusting for clinical characteristics, patients treated by surgeons in groups with a higher proportion of primary care physicians (PCPs) in T1 were less likely to receive MRI in T2 (OR = 0.81 for 10% increase in PCPs, 95% CI = 0.71, 0.93). Surgeon transitivity (ie, clustering of surgeons) was significantly associated with MRI receipt (P = 0.013); patients whose surgeons were in groups with higher transitivity in T1 were more likely to receive MRI in T2 (OR = 1.29 for 10% increase in clustering, 95% CI = 1.06, 1.58). CONCLUSION: The characteristics of a surgeon's peer network are associated with their patients' subsequent receipt of perioperative MRI.

Regional Medicare Expenditures and Survival Among Older Women With Localized Breast Cancer.

BACKGROUND: Despite evidence on large variation in breast cancer expenditures across geographic regions, there is little understanding about the association between expenditures and patient outcomes. OBJECTIVES: To examine whether Medicare beneficiaries with nonmetastatic breast cancer living in regions with higher cancer-related expenditures had better survival. RESEARCH DESIGN: A retrospective cohort study of women with localized breast cancer from the Surveillance, Epidemiology, and End Results-Medicare linked database. Hospital referral regions (HRR) were categorized into quintiles based on risk-standardized per patient Medicare expenditures on initial phase of breast cancer care. Hierarchical generalized linear models were estimated to examine the association between patients' HRR quintile and survival. SUBJECTS: In total, 12,610 Medicare beneficiaries diagnosed with stage II-III breast cancer during 2005-2008 who underwent surgery. MEASURES: Outcome measures for our analysis were 3- and 5-year overall survival. RESULTS: Risk-standardized per patient Medicare expenditures on initial phase of breast cancer care ranged from $13,338 to $26,831 across the HRRs. Unadjusted 3- and 5-year survival varied from 66.7% to 92.2% and 50.0% to 84.0%, respectively, across the HRRs, but there was no significant association between HRR quintile and survival in bivariate analysis (P=0.08 and 0.28, respectively). After adjustment for sociodemographic and clinical characteristics, quintiles of regional cancer expenditures remained unassociated with patients' 3-year (P=0.35) and 5-year survival (P=0.20). Further analysis adjusting for treatment factors (surgery type and receipt of radiation and systemic therapy) and stratifying by cancer stage showed similar results. CONCLUSIONS: For Medicare beneficiaries with nonmetastatic breast cancer, residence in regions with higher breast cancer-related expenditures was not associated with better survival. More attention to value in breast cancer care is warranted.