Abstract 6113: Racial disparity in HER2-positive breast cancer: A single cancer center registry review
Authors: Hodges Alan , Rosenbaum Cornelius , Santana Claudia , Niravath Polly A. , Mai Hanh , Jain Dharamvir , Chang Jenny C. , Xu Jiaqiong , Sun Kai 
Published: March 2024

Background: Racial disparity outcomes in HER2-positive breast cancer have been previously described but the literature is limited. We examined data from our cancer center registry to investigate racial disparity in HER2-positive breast cancer.

Method: We retrospectively queried patients diagnosed with HER2-positive breast cancer from Houston Methodist Cancer Center registry from 2016 to 2022. Patients’ demographics, cancer staging, treatment and outcomes including recurrence and survival were recorded and analyzed. We used the distressed communities index (DCI), a composite metric of multiple socioeconomic factors based on the patient’s zip code at diagnosis, as a surrogate of socioeconomic status. Multivariable logistic regression and Cox proportional hazards analysis were used. A p value &lt;0.05 is considered statistically significant.

Results: From 2016 to 2022, 992 patients were retrieved. 58.4% (579/992) patients were White, 17.3% (172/992) black, 16.2% (161/992) Hispanic and 8.1% (80/992) Asian. Although Black and Hispanic patients lived in more distressed communities, Black and Asian patients were diagnosed with more advanced disease. There were no statistically significant differences in neoadjuvant treatment received and pathologic complete response (pCR) rate among racial groups (table 1). Patients with higher stages are more likely to receive neoadjuvant treatment (OR: 5.49 [CI: 3.61-8.49] and 5.59 [CI: 3.15-10.2] for Stage 2 and 3 respectively). ER-HER2+ subtype was the only predictor of achieving pCR (OR: 0.47, CI: 0.29-0.79). Younger age, receiving neoadjuvant treatment and earlier stages were associated with improved all-cause mortality. There were no differences in receiving neoadjuvant treatment between racial groups, DCI; race and DCI are not associated with pCR or all-cause mortality.

Conclusion: Our retrospective study from a single institution revealed no significant racial disparities in the treatment and outcome of HER2-positive breast cancers.

Table 1. Characteristics of HER2-positive breast cancer in different racial groups Variables Asian, N = 80 Black, N = 172 Spanish, N = 161 White, N = 579 p-value Age (at diagnosis), mean (SD) 54 (13) 54 (12) 53 (13) 57 (13) &lt;0.001 Distressed communities index, mean (SD) 28 (28) 49 (31) 49 (31) 35 (29) &lt;0.001 HER2 subtype 0.7 ER-HER2+ 33/80 (41%) 64/169 (38%) 55/161 (34%) 204/576 (35%) ER+HER2+ 47/80 (59%) 105/169 (62%) 106/161 (66%) 372/576 (65%) Cancer stage 0.010 0 4/80 (5.0%) 4/172 (2.3%) 8/161 (5.0%) 31/579 (5.4%) 1 34/80 (43%) 51/172 (30%) 52/161 (32%) 227/579 (39%) 2 14/80 (18%) 44/172 (26%) 49/161 (30%) 172/579 (30%) 3 12/80 (15%) 30/172 (17%) 23/161 (14%) 52/579 (9.0%) 4 13/80 (16%) 30/172 (17%) 16/161 (9.9%) 63/579 (11%) Unknown 3/80 (3.8%) 13/172 (7.6%) 13/161 (8.1%) 34/579 (5.9%) Received neoadjuvant 0.074 No 31/66 (47%) 68/136 (50%) 54/134 (40%) 263/497 (53%) Yes 35/66 (53%) 68/136 (50%) 80/134 (60%) 234/497 (47%) Complete pathological response 0.9 No 17/35 (49%) 34/70 (49%) 40/75 (53%) 111/230 (48%) Yes 18/35 (51%) 36/70 (51%) 35/75 (47%) 119/230 (52%) Mortality (all cause) 0.052 Alive 76/80 (95%) 150/172 (87%) 147/161 (91%) 540/579 (93%) Dead 4/80 (5.0%) 22/172 (13%) 14/161 (8.7%) 39/579 (6.7%)

Citation Format: Alan Hodges, Cornelius Rosenbaum, Claudia Santana, Polly A. Niravath, Hanh Mai, Dharamvir Jain, Jenny C. Chang, Jiaqiong Xu, Kai Sun. Racial disparity in HER2-positive breast cancer: A single cancer center registry review [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6113.