However, there remains a paucity of robust clinical evidence to guide the adjustment of adjuvant therapy based on minimal residual disease (MRD) status in early-stage breast cancer.<h4>Case presentation</h4>A 69-year-old female patient with early-stage triple-negative breast cancer (TNBC) with somatic BRCA2 mutations exhibited an exceptional response to adjuvant therapy with olaparib. The gene discussed is BRCA2; the disease is triple-negative breast carcinoma.