Patterns of Evidence-Based Care for the Diagnosis, Staging, and First-line Treatment of Breast Cancer by Race-Ethnicity: A SEER-Medicare Study

BACKGROUND

Racial and ethnic disparities in guideline-recommended breast cancer treatment are well documented, however studies including diagnostic and staging procedures necessary to determine treatment indications are lacking. The purpose of this study was to characterize patterns in delivery of evidence-based services for the diagnosis, clinical workup, and first-line treatment of breast cancer by race-ethnicity.

METHODS

SEER-Medicare data were used to identify women diagnosed with invasive breast cancer between 2000 and 2017 at age 66 or older (n = 2,15,605). Evidence-based services included diagnostic procedures (diagnostic mammography and breast biopsy), clinical workup (stage and grade determination, lymph node biopsy, and HR and HER2 status determination), and treatment initiation (surgery, radiation, chemotherapy, hormone therapy, and HER2-targeted therapy). Poisson regression was used to estimate rate ratios (RR) and 95% confidence intervals (CI) for each service.

RESULTS

Black and American Indian/Alaska Native (AIAN) women had significantly lower rates of evidence-based care across the continuum from diagnostics through first-line treatment compared to non-Hispanic White (NHW) women. AIAN women had the lowest rates of HER2-targeted therapy and hormone therapy initiation. While Black women also had lower initiation of HER2-targeted therapy than NHW, differences in hormone therapy were not observed.

CONCLUSIONS

Our findings suggest patterns along the continuum of care from diagnostic procedures to treatment initiation may differ across race-ethnicity groups.

IMPACT

Efforts to improve delivery of guideline-concordant treatment and mitigate racial-ethnic disparities in healthcare and survival should include procedures performed as part of the diagnosis, clinical workup, and staging processes.

Adjuvant treatment of surgically treated bone metastasis patients: association with hospital characteristics and trends over time

Patients with metastatic disease of the bone (MDB) often require surgical stabilization; however, there is not widespread consensus on subsequent adjuvant management. This study aimed to characterize utilization of perioperative adjuvant treatment among MDB patients. We identified 9413 surgically treated MDB patients with primary (breast, kidney, lung, prostate, or multiple myeloma) cancer from Surveillance, Epidemiology, and End Results (SEER)-Medicare data. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for receipt of chemotherapy, radiation, and bisphosphonates, respectively, in the adjuvant setting (90 days before or after surgery) by hospital characteristics-medical school affiliation, surgery volume, and Commission on Cancer (CoC) accreditation. Trends in treatment utilization by year of surgery were assessed via bar charts and Chi-square tests for trend. Patients surgically treated at major medical schools or high-volume facilities (compared to no medical school affiliation and low volume) had significantly higher odds of receiving radiation and chemotherapy, independent of patient and tumor characteristics (OR (95% CI); medical school: radiation 1.33 (1.19-1.49), chemotherapy 1.15 (1.02-1.30); and high volume: radiation 1.22 (1.11-1.34), chemotherapy 1.11 (1.02-1.22)). Patients surgically treated at CoC-accredited institutions, compared to non-accredited, had significantly higher odds of receiving radiation and bisphosphonates [radiation 1.24 (1.13-1.36); bisphosphonates 1.15 (1.04-1.28)]. Use of chemotherapy and bisphosphonates increased while radiation use declined over the study period from 1991 to 2014. Medical school affiliation, hospital volume, and CoC accreditation are associated with receipt of adjuvant treatment to prevent or manage pathologic fractures in MDB patients. Further investigation is needed to determine whether these associations reflect delivery of optimal care.

The Influence of Hospital Characteristics on Patient Survival in Surgically Managed Metastatic Disease of Bone: An Analysis of the SEER-Medicare Linked Database

OBJECTIVES

We investigated whether patients receiving surgical treatment for metastatic disease of bone (MDB) at hospitals with higher volume, medical school affiliation, or Commission on Cancer accreditation have superior outcomes.

MATERIALS AND METHODS

Using the Surveillance, Epidemiology, and End Results-Medicare database, we identified 9413 patients surgically treated for extremity MDB between 1992 and 2014 at the age of 66 years or older. Cox proportional hazards models were used to calculate the hazards ratios (HR) for 90-day and 1-year mortality and 30-day readmission according to the characteristics of the hospital where bone surgery was performed.

RESULTS

We observed no notable differences in 90-day mortality, 1-year mortality, or 30-day readmission associated with hospital volume. Major medical school affiliation was associated with lower 90-day (HR: 0.88, 95% confidence interval [CI]: 0.80-0.96) and 1-year (HR: 0.92, 95% CI: 0.87-0.99) mortality after adjustments for demographic and tumor characteristics. Surgical treatment at Commission on Cancer accredited hospitals was associated with significantly higher risk of death at 90 days and 1 year after the surgery. This effect appeared to be driven by lung cancer patients (1-year HR: 1.17, 95% CI: 1.07-1.27).

CONCLUSIONS

Our findings suggest surgical management of MDB at lower-volume hospitals does not compromise survival or readmissions. There may be benefit to referral or consultation with an academic medical center in some tumor types or clinical scenarios.

Disparities in breast cancer stage at diagnosis between immigrant and native-born women: A meta-analysis

PURPOSE

To synthesize existing observational evidence to identify disparities in stage at breast cancer diagnosis between foreign- and native-born women. We hypothesized immigrant women would be less likely than natives to be diagnosed at a localized stage.

METHODS

Systematic searches for studies detailing stage at breast cancer diagnosis by birthplace in PubMed, Embase, and Web of Science yielded 11 relevant cohort studies from six countries. Odds ratios were pooled using random effects models.

RESULTS

Foreign-born women were 12% less likely to be diagnosed with breast cancer at a localized stage than natives (OR 0.88, 95% CI 0.82-0.95). A similar disadvantage was observed in immigrants from Asia, Eastern Europe, Latin America and the Caribbean, and developing or in transition nations; immigrants from developed countries experienced the least disparity.

CONCLUSIONS

This meta-analysis confirmed the presence of significant differences in breast cancer stage at diagnosis as per nativity. Across diverse immigrant groups and host countries, foreign-born women were significantly less likely to be diagnosed with localized breast cancer than native women; the magnitude of the disparity varied by region and economic condition of immigrants' birthplace.