Young breast cancer patients have a high probability of a genetic predisposition, and identifying hereditary diseases, such as HBOC with pathogenic variants in the BRCA1/BRCA2 genes and Li-Fraumeni syndrome with pathogenic variants in the TP53 gene.25) In this case report, the patient’s family history included a maternal grandmother diagnosed with breast cancer at an advanced age, but there was no other HBOC-related family history. The gene discussed is TP53; the disease is hereditary disease.