title: Extra-nodal lymphoma presenting as a mimic of soft-tissue sarcoma.
abstract: BACKGROUND
  A variety of soft-tissue tumours result in soft-tissue masses, which are all differential diagnoses of soft-tissue sarcomas. A rare cause is extra-nodal lymphoma which, unlike a soft-tissue sarcoma which it mimics, should not be excised, but rather treated by chemotherapy and/or radiotherapy. The aim of the present study was to identify clinical, radiological, biopsy and management features of lymphoma when presenting as a soft-tissue mass.
  
  
  METHODS
  A review of 17 cases of soft-tissue lymphoma presenting as a soft-tissue mass from a total database of 295 soft-tissue tumours was undertaken. Lymphomas arising in cervical, axillary and inguinal nodes were excluded.
  
  
  RESULTS
  All patients presented with a soft-tissue mass but none had the symptoms of lymphoma. Computed tomography scanning identified seven (54%) of 13 with regional lymphadenopathy, six (46%) of 13 with encasement of major vascular structures and three with invasion across major soft-tissue boundaries. Core biopsy established a diagnosis in 13 patients (sensitivity 93%). All patients were treated with either chemotherapy and/or radiotherapy and all are alive with a mean follow up of 19 months. None underwent major resectional surgery.
  
  
  CONCLUSIONS
  The present series highlights a rare subgroup of patients with extra-nodal soft-tissue lymphoma mimicking soft-tissue sarcoma. Core biopsy is accurate in their diagnosis. Computed tomography scanning may show features suggesting the diagnosis.
authors.affiliation: Department of Surgery, Alfred Hospital, Monash University, Victoria, Australia.
authors.forename: Brett
authors.initials: B
authors.lastname: Knowles
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Serpell
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy / Q000379:methods; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008223:Lymphoma / Q000175:diagnosis* / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012509:Sarcoma / Q000175:diagnosis* / Q000601:surgery; D012983:Soft Tissue Neoplasms / Q000175:diagnosis* / Q000601:surgery; D014057:Tomography, X-Ray Computed