422P - Disparities in treatment delays among metastatic breast cancer patients: Insights from nationwide electronic health records, 2011-2022

Background

Despite previous research highlighting treatment delay inequities in early-stage breast cancer specifically in historically marginalized groups, there is limited research on disparities in Metastatic Breast Cancer (MBC) treatment delays. This study explores treatment delay disparities in MBC treatment initiation aiming to identify contributing factors crucial for improving timely access to care for all.

Methods

Nationwide Flatiron Health electronic health records-derived deidentified database, including females aged 18+ diagnosed with MBC in the U.S. between 2011 and 2022. Treatment delay, defined as a binary variable (1 for delays >60 days between diagnosis and first-line treatment), was assessed. Statistical tests (t-tests and chi-squared) were used to analyze patient characteristics (age, race, health insurance, stage at diagnosis, site of metastasis, phenotypes, etc.) among groups with and without treatment delays. Logistic regression was employed to evaluate the association between clinical and non-clinical factors and treatment delays.

Results

Among 20,617 patients with MBC, nearly 28% had treatment delays. Patients with treatment delays were younger, uninsured, historically marginalized patients, and newly diagnosed as compared to patients without treatment delays. Logistic regression revealed higher age was associated with lower odds of treatment delays (2%, p=0.01). Patients without health insurance coverage had higher delay odds (OR: 3.16 p=0.001) as compared with those with commercial health insurance. Historically marginalized patients showed a higher likelihood of delays, ranging from 6% for Black patients to 38% for Hispanic patients (p=0.03) compared to White patients.

Conclusions

Our study highlights concerning disparities in MBC treatment delays. Patients from historically marginalized groups, and those without health insurance coverage are more likely to experience delays in MBC treatment initiation. Identifying and addressing these disparities is essential to ensure equitable healthcare and enhance overall outcomes.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

American Cancer Society.

Disclosure

G. Kimmick: Financial Interests, Advisory Board, 5/31/2018: Eisai ; Financial Interests, Advisory Board, 3/22/2018-3/23/2018: Boehringer Ingelheim 2018 ; Financial Interests, Advisory Board, 10/1/2020: Immunomedics; Financial Interests, Advisory Board, 3/23/2021: Biotheranostics; Financial Interests, Advisory Board, 7/12/2023: Novartis; Other, Personal, Advisory Role, 2019: Genomic Health 2019, Agendia; Other, Personal, Speaker’s Bureau, Interview with Niel Love 11/19/2021: Research-to-Practice; Financial Interests, Royalties: UpToDate, Springer; Other, Personal and Institutional, Research Funding: Abbott Laboratories, AbbVie, Abraxis BioScience, Alphavax, AstraZeneca, Bionovo, BiPar Sciences, Bristol Meyers Squibb, Celldex Therapeutics, Celsion, EMD Serono, Exelixis, Genentech, GSK (CARG Trial), Incyte Corporation. All other authors have declared no conflicts of interest.