Abstract Background: Patients at increased risk of breast (BC) and/or ovarian (OC) cancer can opt for risk-reducing surgeries (RRS). However, there are disparities in access to genomic cancer risk assessment (GCRA) and cancer prevention interventions related to geography, socioeconomic status, and limited public health support. We studied factors that affect the uptake of risk-reducing mastectomy (RRM) and salpingo-oophorectomy (RRSO) in Hispanic patients of Latin America (LatAm) and the United States (US). Methods: Hispanic women enrolled in the Clinical Cancer Genomics Community Research Network registry between 1997-2019 who underwent genetic testing, had a personal or family history (FHX) of BC or OC, and had ≥6 months of follow-up data were considered eligible. Demographic and clinical factors associated with risk-appropriate uptake of RRS were considered. Data were analyzed using Fisher’s exact tests and logistic regression models. Results: 1818 patients with a median follow-up of 43 months were studied. Most were from the US (65%), followed by Mexico (21%), Peru (10%), Colombia (2%), and Puerto Rico (2%). Median age at enrollment was 44 years; 81% had a personal history of BC and 5% of OC. Cancer-associated pathogenic variants (PVs) were identified in 459 patients (25%); 409 were in BRCA, 36 had other BC-susceptibility PVs (ATM, CHEK2, PALB2, PTEN, or TP53), and 14 had other OC-susceptibility PVs (BRIP1, MSH2, MSH6, MLH1, or RAD51C). Overall, 449/1715 (26.2%) patients underwent RRM, with a higher rate among patients in the US than those in LatAm (31% vs. 17%, p<0.01); 377/1517 (25%) patients underwent RRSO, with no regional differences observed (24% vs. 27%, p=0.22). The factors associated with undergoing RRM were US residence (OR 2.2; 95% CI 1.7-2.8), age ≤50 (OR 2.2; 95% CI 1.7-2.8), carrying a BC-predisposing PV (OR 3.5; 95% CI 2.8-4.4), positive FHX for BC (OR 1.5; 95% CI 1.2-1.9), and personal history of cancer (OR 3.6; 95% CI 2.4-5.6). In a multivariate model, US residence, age, and previous BC diagnosis remained independent predictors for RRM in BC-susceptibility gene PV carriers, while age was not a significant factor in non-carriers. The factors associated with undergoing RRSO included being a carrier of an OC-predisposing PV (OR 6.3; 95% CI 4.8-8.1), positive FHX for OC (OR 2.1; 95% CI 1.5-2.8), and previous cancer diagnosis (OR 1.7; 95% CI 1.2-2.5). In carriers of OC-susceptibility gene PVs, residing in US and previous cancer diagnosis were independently associated with RRSO, while positive FHX for OC and previous cancer diagnosis were identified as independent factors in non-carriers. Conclusion: There are disparities in the uptake of RRS outside the US. Beyond limitations in resources, understanding the factors associated with undergoing RRS could be key to developing targeted interventions to improve the uptake of risk-appropriate measures in hereditary cancer syndrome patients. Citation Format: Jeffrey N. Weitzel, Yanin Chavarri-Guerra, Ana Ferrigno, Pamela Mora-Alférez, Annette Campbell-Fontaine, Cynthia Villarreal-Garza, Alejandro Mohar-Betancourt, Gubidxa Gutierrez-Seymour, Gary W. Unzeitig, Sandra Brown, Bita Nehoray, Azucena del Toro-Valero, Pamela Ganschow, Ian Komenaka, Yenni Rodriguez, Francisco Gutierrez-Delgado, Kathleen R. Blazer. Disparity in the uptake of risk-reducing surgery after GCRA in Hispanic patients in Latin America and in the United States [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2214.