A rare case of multifocal/multicentric breast cancer in a young female: a case report and literature review.

Background: Multifocal (MF) and multicentric (MC) breast cancers (MMBC) refer to the presence of more than two synchronous ipsilateral breast carcinomas. MMBC with more than 2 foci is a relatively rare case, and the heterogeneity among different foci requires a comprehensive consideration for its surgical strategy and other treatment. Case Description: The patient was a 38-year-old woman who accidentally discovered self-palpable masses in the upper quadrant breast. Preoperative mammography showed atypical results, and ultrasound and breast dynamic contrast-enhanced magnetic resonance imaging supplemented the evaluation. Considering her condition of more than ten potential foci, relatively small breast and the patient's request, the mastectomy surgical strategy was chosen for the cosmetic outcome. The pathological analyses and immunochemical staining demonstrated similarity between different foci, and the postoperative treatment was made according to a comprehensive consideration among lesions. Conclusions: Early and accurate diagnosis of MMBC is critical, and more accurate preoperative diagnosis relies on breast magnetic resonance imaging beyond ultrasound and mammography. In this case of multiple lesions, extensive lesions, multi-center lesions and small breasts, mastectomy is first under consideration, while the false positivity from imaging evaluation requires attention. The heterogeneity among foci in MMBC cannot be overlooked and necessitates a comprehensive understanding for guiding surgical and other therapeutic interventions.