A single institution study on the demographics and response rates of Hispanic women with HER2+ disease.

Abstract

e19069 Background: Hispanics have 20% lower incidence of breast cancer than the general US population. Despite this, breast cancer is the leading neoplasm seen in Hispanics and is a significant cause of their mortality. Our study reports the incidence and outcome of HER2 breast cancer, use of a neoadjuvant regimen, and surgery type in the Hispanic population at our urban institution. Methods: This study reports on 37 women that were diagnosed with HER2+, non-metastatic breast cancer from 2015-2019. We report this as a single institution, community program that provides equal access healthcare and delivery. Our data was investigated and compiled using our facility’s cancer registry. The patient sample included 20(54%) Hispanics, 13(35%) African Americans, 3(8.0%) Caucasians and 1(3%) Asian. Of the 20 Hispanic women, 85% were Estrogen Receptor (ER) positive and 48% were Progesterone Receptor (PR) positive. Eleven (55%) of the 20 Hispanic patients(pts) received neoadjuvant chemotherapy (NAC), which included regimens containing Trastuzamab (H) with or without Pertuzumab(P). Our remaining 9 pts receiving adjuvant therapy were investigated for response as well. Results: Our Hispanic pts receiving NAC had an overall complete response rate of 45% and a partial response rate of 55%. There appeared to be no significant difference in response rate in Hispanic women between the HP group versus H. NAC pts had fewer partial mastectomies performed than those not receiving NAC. Hispanic NAC patients were found to have significantly more sentinel lymph node dissections (SLND) 7(88%) versus axillary lymph node dissections 1(16%) compared to other ethnicities receiving NAC. Non NAC Hispanic patients had 56% sentinel lymph node dissections, compared to 44% complete axillary dissections. Conclusions: The results indicate that there is a significant Hispanic population at our facility that harbor the HER2 oncogene. These pts seem to have a promising response to the NAC regimen in regards to SLND. We hope to have a larger patient sample through a multi-institution study, with statistical analysis to support our current findings. More studies should be performed on Hispanic women with HER2 disease, as data with this subset of population is lacking. The NAC regimen should be greatly considered and implemented in the treatment in those looking to downstage axillary disease. We hope to further investigate treatment options for Hispanic pts to gain greater pathological responses, leading to improved progression free and disease free survival that match that of other ethnic groups.