title: Primary muscle lymphoma: clinical and imaging findings.
abstract: OBJECTIVE
  To assess the clinical and imaging findings in primary muscle lymphoma.
  
  
  METHODS
  Seven patients with biopsy-proved primary muscle lymphoma without evidence of systemic disease underwent imaging with plain radiography or computed tomography (CT) and magnetic resonance (MR) imaging. Four underwent bone scintigraphy, and two underwent gallium scintigraphy and fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) before and after therapy.
  
  
  RESULTS
  Plain radiographs at initial examination (n = 5) showed no bone abnormalities. Soft-tissue masses and bone marrow involvement showed isoattenuation at CT (n = 3), but at MR imaging (n = 7), all masses demonstrated increased signal intensity on T2-weighted images that involved multiple muscle compartments and typically spanned a long segment of the extremity. Adjacent bone disease was less extensive than muscle disease, and, in most cases, subcutaneous stranding or extension was observed adjacent to the masses. Good size correlation was observed between findings at MR imaging, gallium scintigraphy, and FDG PET. Two patients developed recurrent multifocal muscle lymphoma several years after initial examination.
  
  
  CONCLUSIONS
  The presence of an extensive soft-tissue mass with infiltration of adjacent subcutaneous fat and minimal or no extension into the bone marrow cavity at MR imaging and normal plain radiographic findings may suggest primary muscle lymphoma.
authors.affiliation: Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: V S
authors.initials: VS
authors.lastname: Lee
authors.forename: S
authors.initials: S
authors.lastname: Martinez
authors.forename: R E
authors.initials: RE
authors.lastname: Coleman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001842:Bone and Bones / Q000000981:diagnostic imaging; D003847:Deoxyglucose / Q000031:analogs & derivatives; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D005710:Gallium Radioisotopes; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019042:Muscle Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014055:Tomography, Emission-Computed; D014057:Tomography, X-Ray Computed
chemical_list: D005462:Fluorine Radioisotopes; D005710:Gallium Radioisotopes; D019788:Fluorodeoxyglucose F18; D003847:Deoxyglucose