Malignant lymphoma of the breast in a male patient: ultrasound imaging features.

Non-Hodgkin lymphoma (NHL) of the breast is a rare disease. Herein, we report a rare case of secondary involvement of the breast by NHL in a male patient and the ultrasound imaging findings. A 70-year-old man noticed an induration of the subareolar region of the right breast. He had been diagnosed as having mantle cell lymphoma 5 years before and treated with several series of chemoradiotherapy. On supine examination, palpation revealed bilateral breast enlargement, but detection of a lump was difficult. Ultrasonography showed a hypoechoic non-mass image-forming lesion in the subareolar region of the right breast. The final pathological diagnosis was recurrence of mantle cell lymphoma in the right breast. The diagnosis of malignant lymphoma of the breast by imaging modalities is difficult because there are no specific features. Breast lymphoma should be included with gynecomastia and breast cancer in the differential diagnosis of male patients with breast enlargement.