title: MR imaging of malignant primary breast lymphoma: including diffusion-weighted imaging, histologic features, and a literature review.
abstract: OBJECTIVE
  To investigate the magnetic resonance (MR) imaging characteristics of malignant primary breast lymphoma (PBL), including features on diffusion-weighted imaging (DWI).
  
  
  METHODS
  The MR findings of three patients were reviewed retrospectively at our institutions. The signal intensity, shape, enhancement pattern, and DWI findings were examined and correlated with the histologic features. We also reviewed the MR findings of cases of PBL reported in the literature.
  
  
  RESULTS
  The tumors in our cases showed early enhancement with penetrating vessels on early-phase dynamic MR images and a strong high signal intensity on DWI. The tumors had a cerebroid appearance and septal enhancement on delayed contrast-enhanced MR images, and we speculate that the fibrous tissue seen in the tumors may correspond to septal enhancement. After chemotherapy, all lesions decreased in size, while the ADCs were increased. All of the cases reported in the literature showed early or avid enhancement; this finding was similar to that observed in our cases.
  
  
  CONCLUSIONS
  Although based on a small number of cases, we suggest that strong enhancement with penetrating vessels in masses on early images of dynamic MR, strong high intensity on DWI, a cerebroid appearance, and septal enhancement are useful diagnostic clues for a diagnosis of PBL.
authors.affiliation: Department of Radiology, Clinical Research Institute, National Kyushu Medical Center, 1-8-1 Jigyohama, Chuo-ku, Fukuoka, 810-8563, Japan, radmad311@yahoo.co.jp.
authors.forename: Roka Namoto
authors.initials: RN
authors.lastname: Matsubayashi
authors.forename: Yuka
authors.initials: Y
authors.lastname: Inoue
authors.forename: Seiichi
authors.initials: S
authors.lastname: Okamura
authors.forename: Seiya
authors.initials: S
authors.lastname: Momosaki
authors.forename: Takahiko
authors.initials: T
authors.lastname: Nakazono
authors.forename: Toru
authors.initials: T
authors.lastname: Muranaka
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008223:Lymphoma / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D013382:Subtraction Technique
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA