3180 - Effect of Ethnic Concordance in Post-Treatment Follow-Up and Surveillance of Korean American Breast Cancer Patients Treated with Adjuvant Radiotherapy

H. R. Han¹, I. Kang², J. C. Ye³, D. C. Ling³, S. X. Bian¹, N. Lee⁴, G. K. In⁴, S. H. Ahn⁴, and S. K. Yoo¹; ¹Department of Radiation Oncology, Los Angeles General Medical Center, Los Angeles, CA, ²Keck School of Medicine, University of Southern California, Los Angeles, CA, ³Department of Radiation Oncology, University of Southern California Keck School of Medicine, Los Angeles, CA, ⁴Department of Medical Oncology, Keck School of Medicine, University of Southern California, Los Angeles, CA

Purpose/Objective(s): Ethnic concordance in patient-physician relationships helps patients navigate unique population challenges, improving follow-up compliance, health literacy, and treatment outcomes in various medical settings. Dense breasts have increased prevalence in Korean females compared to general female populations of the United States (50-60% versus 40-50%) and pose distinctive challenges to routine post-treatment screening recommendations as small masses may be obscured with standard mammography (MMG) alone, warranting additional imaging techniques. Here, we investigate ethnic concordance effects on Korean American breast cancer patients who undergo radiotherapy (RT). We aim to investigate the effect of ethnic concordance on post-RT follow-up and breast cancer imaging in Korean American breast cancer patients treated with adjuvant RT. Materials/

Methods: Institutional databases at XXXX were retrospectively reviewed for Korean American patients with Stage 0-III breast cancers who underwent surgery and adjuvant RT between 2013-2023. Patients were categorized into two cohorts, those with ethnic concordance with their physicians vs those with ethnic discordance. Post-RT breast cancer screening modalities were reviewed for whether patients with baseline heterogeneously or extremely dense breasts received routine MMG with additional imaging, including ultrasounds or MRI. Time to first post-RT and second post-RT follow-up visits were recorded. Two sample Z tests were used to compare cohort proportions for ordering additional breast imaging beyond MMG. Two-tailed Mann-Whitney U test was used to compare follow-up times.
Results: A total of 102 patients were identified with a median age of 62.8 (range 33.0-89.1). Most patients (88.2%) had hormone receptor-positive disease; 15.7%, 48.0%, 29.4%, and 6.9% had stage 0, I, II, and III disease, respectively. Lumpectomy and mastectomy were performed in 90.2% and 19.8% of patients, respectively. Of all patients, 70.6% (n=72) had ethnic concordance with their providers and 29.4% (n=30) had ethnic discordance. Of all patients, 73.5% (n=75) had heterogeneously or extremely dense breasts, of which patients in ethnic concordance with their providers were more likely to receive additional breast imaging beyond MMG in post-RT yearly screening, 75% vs 52% (z=-5.1; p=0.03). Median time was 2 weeks vs 7 weeks (p<0.01) to first follow-up visit post-RT and 1 month vs 6 months (p<0.01) to second follow-up visit post-RT in ethnic concordance vs discordance groups, respectively.
Conclusion: Korean American patients who had patient-provider ethnic concordance were significantly more likely to receive additional imaging evaluation beyond routine MMG screening alone and have statistically significant shorter interval times for post-RT follow-up visits.