BRCA1/2  negative early onset Breast Cancer
Early-onset Breast Cancer (EOBC) represents a small but clinically aggressive subset of breast cancer cases. While pathogenic variants in BRCA1/2 might explain some of this risk, many EOBC cases remain unexplained. This study aimed to investigate rare germline variants in DNA repair genes that may contribute to EOBC among BRCA1/2-negative patients.