Abstract PS8-25: Genetic cancer risk assessment and its impact on the uptake of cancer risk reduction strategies: The experience of a Mexican center
Authors: Aguilar Dione , Aranda-Gutierrez Alejandro , Ferrigno Ana S , Weitzel Jeffrey N , Blazer Kathleen N , Castillo Danielle , Herzog Josef , Mejia Rosa , Sada-Villarreal Nancy L , Cardona Servando , Canavati-Marcos Mauricio , Garza-Montemayor Margarita , Villarreal-Garza Cynthia 
Published: February 2021

Background: The implementation of genetic cancer risk assessment (GCRA) in resource-constrained settings is limited due to multiple factors, including insufficient access to preventive strategies. In our center, GCRA was formally established in 2014, and access to genetic testing is provided to underserved patients through a research collaboration with City of Hope's CCGCRN. The aim of this study is to determine the proportion of patients with germline mutations that underwent risk-reducing surgeries (RRS) and followed recommended breast cancer (BC) screening strategies.

Methods: Patients that received GCRA in a center located in Monterrey, Mexico who met NCCN criteria for testing for BC predisposition genes were eligible. Information on mutation status, performance of RRS and BC screening strategies was prospectively collected. The patients were grouped by type of healthcare (i.e. private vs public), with differences explored using Fisher's exact or Mann Whitney U tests, as appropriate.

Results: Between 2014 and 2019, a total of 437 probands and 139 of their relatives underwent GCRA. Of these, 23% and 37% were identified as mutation carriers, respectively: BRCA1/2 (72.5%), PALB2 (6.4%), CHEK2 (6.4%) and others (14.7%). The median time elapsed from disclosure of genetic test results to collection of data was 16 months. The median age was 41 years, with no statistical difference according to type of healthcare. Based on NCCN guidelines, 151 RRS were recommended according to mutational status and age, of which 52 (34%) were performed: 28 risk-reducing mastectomies (RRM) and 24 risk-reducing salpingo-oophorectomies (RRSO). A substantial proportion of these were funded by non-governmental organizations, while the rest were covered by public health insurance (as adjuvant treatment), private health insurance or the patient herself. Regarding BC screening, after excluding 78 patients because of active BC treatment, bilateral mastectomy or male sex, 92% of eligible patients followed NCCN recommendations. No differences in the performance of RRS or BC screening strategies were found according to type of healthcare delivery.

Conclusion: In this cohort, an adequate adherence to recommended screening strategies was observed but only one-third of recommended RRS were performed. Notably, type of healthcare was not a determining factor for the adherence to NCCN's recommended prevention strategies, suggesting that economical barriers might not be the main limiting factor. Efforts to elucidate if sociocultural barriers limit adherence to RRS are being conducted in order to enhance standard of care at Mexican centers with GCRA programs.

Characteristics according to healthcare coverage.Private insurancePublic insurancep valueMutational status- Probands: carriers/tested32/117 (27%)67/320 (21%)NS- Relatives: carriers/tested10/42 (24%)42/97 (43%)0.036RRS- RRM performed/recommended9/24 (38%)19/65 (29%)NS- RRSO performed/recommended6/18 (33%)18/44 (41%)NS- RRS covered by NGOs0 (0%)11/37 (30%)0.022Current BC screening modality- Mammogram (MMG) ± US9 (41%)33 (65%)0.033- MRI ± MMG ± US9 (41%)6 (12%)- None3 (14%)1 (2%)- Unknown1 (5%)11 (22%)Follow BC screening recommendations- Yes19 (90%)37 (93%)NS- No2 (10%)3 (8%)

Citation Format: Dione Aguilar, Alejandro Aranda-Gutierrez, Ana S Ferrigno, Jeffrey N Weitzel, Kathleen N Blazer, Danielle Castillo, Josef Herzog, Rosa Mejia, Nancy L Sada-Villarreal, Servando Cardona, Mauricio Canavati-Marcos, Margarita Garza-Montemayor, Cynthia Villarreal-Garza. Genetic cancer risk assessment and its impact on the uptake of cancer risk reduction strategies: The experience of a Mexican center [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS8-25.