Primary Non-Hodgkin's Lymphoma of the Male Breast: A Case Report.

A 69-year-old Japanese man presented with bilateral gynecomastia and a soft, mobile and clearly defined mass beneath the left nipple. A round radiopaque masswas revealed on mammography. The tumor was homogeneous, hypoechoic and measured2.4 x 3.9 cm on ultrasonography. Based on a diagnosis of malignant lymphoma by needle aspiration cytology, a modified radical mastectomy with ipsilateral axillary lymph node dissection was performed. Malignant diffuse large B-cell type lymphoma was diagnosed histologically. Whole body examinations revealed no evidenceof other tumors. Three courses of adjuvant CHOP therapy were subsequently performed. The patient is free of recurrence 12 months after surgery. Primary non-Hodgkin's lymphoma (NHL) of the male breast is extremely rare. The occurrence of lymphoma in this patient could be related to elevated estrogen levels.