Abstract 6133: Genetic profiling landscape among gynecological and breast cancer patients in the borde city of Tijuana, Mexico: A comprehensive study
Authors: Guadarrama-Orozco Jorge Alberto , Leal-Anaya Paula , Guerrero-Santillan Eva 
Published: March 2024

Background: Individuals in Tijuana have been identified as having multicultural and racial diversity. In Baja, California, Mexico, the prevalence and composition of cancer-predisposing germline variants in gynecologic cancers in Tijuana patients have not been evaluated.

Aim and Methods: We aimed to evaluate the prevalence of pathogenic variants (PV) using a panel of 84 cancer-predisposing genes in breast, endometrial, and ovarian cancer from the General Hospital of Tijuana during the period of October 2021-October 2023, who were contacted and invited to participate in the evaluation. Pre- and post-test genetic counseling was given, and a questionnaire on personal, gyneco-obstetric, demographic, and lifestyle variables was conducted. Peripheral blood samples were obtained from all patients, and Next-generation sequencing (NGS) was performed on the Illumina commercial platform (Illumina, SD, USA). Variants were classified according to the American College of Medical Genetics and Genomics (ACMG). Data was collected and descriptive statistics was applied to describe the characteristics of the population.

Results: A total of 51 patients were included in our cohort; 98.0% (50/51) were females and 2% (1/51) were males. Among study participants (mean age ±standard deviation: 46.1 ± 10.9), 49% reported a personal history of cancer (25/51). Diagnosis of breast cancer was present in 80.3% of the patients (41/51), 9% (5/51) with ovarian cancer, and 3.9% (2/51) with endometrial cancer. Twenty-five percent of participants (13/51) harbor a PV or likely pathogenic (LP) variant distributed among four cancer-risk genes (BRCA1, BRCA2, ATM, and TP53). The distribution by gene in the patients with a PV was: BRCA1 in 61% (8/13), BRCA2 in 23% (3/13), TP53 in 8% (1/13), and ATM in 8% (1/13). Whereas 39.2% (20/51) had variants of uncertain clinical significance in genes with ambiguous or non-well-established risk association for cancer (BARD1, AXIN2, GPC3, NF2, CEBPA, MSH3, ALK, DIS3L2, CDC73, BAP1, RAD51D, NF1, MSH2, BLM, NBN, BRCA2, BARD1, RUNX1, RECQL4, EGFR, PALB2, CASR, and POLD1), and 35.2% (18/51) had negative results for both; PV and VUS.

Conclusion: Our findings show a diverse pathogenic variant composition among the recruited individuals of the gynecological cancer population in Tijuana, Mexico, consistent with being a high-risk population for genetic diseases, which warrants further investigation to adequately assess the burden of hereditary cancer and implement appropriate preventative programs. Disparities in access to testing have a significant impact on affected populations, due in part to underrepresentation in surveys of regional cancer etiology and in genomic variant databases.

Citation Format: Jorge Alberto Guadarrama-Orozco, Paula Leal-Anaya, Eva Guerrero-Santillan. Genetic profiling landscape among gynecological and breast cancer patients in the borde city of Tijuana, Mexico: A comprehensive study [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 6133.