F-18 FDG positron emission tomography in non-Hodgkin lymphoma of the breast.

The breast is an uncommon site of development of extranodal non-Hodgkin lymphoma (NHL). Both primary and secondary involvement of the breast have been reported. A 36-year-old woman diagnosed with NHL underwent multimodality imaging for staging of the disease. CT of the chest revealed no significant abnormalities. Whole-body FDG PET imaging showed intense FDG uptake in the left breast. Cytologic examination confirmed breast involvement by diffuse large B-cell NHL. Although rare, breast involvement characterized by increased FDG uptake can occur in patients with lymphoma. This case highlights the role of FDG PET in patients with suspected lymphoma in dense breasts that can be missed by CT scan and mammogram.