Plasmocitoma extramedular mamario: reporte de caso y revisión de la literatura.

Extramedullary plasmacytoma is a rare neoplasm, and involvement of the breast is extremely uncommon, with approximately 83 cases reported since 1928. We present the case of a 63-year-old patient with a history of multiple myeloma, who presented with a one-month history of a rapidly progressing, painless, soft mass measuring 4.5 cm in the right breast. Breast ultrasound showed a Bi-RADS 4 lesion, and due to suspicion of malignancy, a biopsy was performed and the patient was referred to the mastology department. Basic pathological and immunohistochemical studies concluded that the injury corresponded to an extramedullary plasmacytoma. After multiple lines of oncological treatment, the breast plasmacytoma showed an excellent clinical and imaging response. The case is described, and a literature review is presented. [ABSTRACT FROM AUTHOR]