Cancer Management and Research (Jun 2021)
Patterns and Prevalence of BRCA1 and BRCA2 Germline Mutations Among Patients with Triple-Negative Breast Cancer: Regional Perspectives
Abstract
Hikmat Abdel-Razeq,1,2 Faris Tamimi,1 Lama Abujamous,3 Sara Edaily,1 Mahmoud Abunasser,1 Rayan Bater,1 Osama Salama1 1Department of Internal Medicine, King Hussein Cancer Center, Amman, Jordan; 2Department of Internal Medicine, School of Medicine, University of Jordan, Amman, Jordan; 3Department of Cell Therapy & Applied Genomic, King Hussein Cancer Center, Amman, JordanCorrespondence: Hikmat Abdel-RazeqDepartment of Internal Medicine, King Hussein Cancer Center, Queen Rania Al Abdullah Street, P.O. Box: 1269, Amman, 11941, JordanTel +962-6 5300460, Ext: 1000Email [email protected]: Among all subtypes, patients with triple-negative (TN) breast cancer is known for their poor outcome and their higher risk of harboring BRCA1 or BRCA2 pathogenic mutations. Identification of such mutations has clinical impact on breast and ovarian cancer prevention and treatment decisions. We here report on patterns and prevalence of BRCA1 and BRCA2 mutations among Arab patients diagnosed with TN subtype.Patients and Methods: Patients with TN-breast cancer (n=197) were enrolled regardless of their age or family history. Following a detailed genetic counseling, BRCA1/2 testing was performed at reference labs. BRCA1 and BRCA2 variants were classified as negative, pathogenic/likely pathogenic (positive) and variants of uncertain significance (VUS).Results: Median age of enrolled patients was 42 (range, 19– 74) years and 27 (13.7%) were non-Jordanian Arabs. Among the study group, 50 (25.4%) were tested positive for BRCA1 (n=36, 18.3%) or BRCA2 (n=14, 7.1%), while 14 (7.1%) others had VUS. Compared to older ones, mutation rates were higher among patients < 40 years (32.9%, P= 0.034), those with close relatives with breast, ovarian, pancreatic or prostate cancer (37.8%, P=0.002) and those with two or more breast cancers (41.4%, P=0.032). Among eligible patients, 23 (63.9%) patients underwent prophylactic mastectomy, while 19 (52.8%) patients had risk-reducing salpingo-oophorectomy. None of the patients with VUS underwent any prophylactic surgery.Conclusion: Arab patients with TN-breast cancer have relatively high BRCA1 or BRCA2 mutation rates. Young age at diagnosis and personal and family history of breast cancer further increase this risk.Keywords: cancer genetics, genetic consultation, genetic variants, women’s cancer, breast cancer, BRCA1/2 mutation