title: [Mediastinal space-occupying lesion of uncertain histology: difficulties of differential diagnosis].
abstract: METHODS
  A 78-year-old woman had, for the previous 4 months, been aware of an easily moveable tumour in the jugular region. She had been feeling well except for general fatigue. Physical examination revealed a mass in the jugular region, a little over 2 cm in diameter.
  
  
  METHODS
  Routine laboratory tests were normal, except for a raised erythrocyte sedimentation rate. After ultrasound, scintigraphy and computed tomography, a biopsy was performed. Histologically it was suspicious of a centroblastic centrocytic non-Hodgkin lymphoma, but further pathological investigation established the diagnosis of a malignant thymoma.
  
  
  METHODS
  The tumour was resected and histological examination confirmed a malignant thymoma with infiltration of surrounding tissues. Radiotherapy was subsequently undertaken.
  
  
  CONCLUSIONS
  Even though its evidence is low, a malignant thymoma or benign thymic tumour should be included in the differential diagnosis of a space-occupying mediastinal mass of unclear histology.
authors.affiliation: Internistische Gemeinschaftspraxis, Evangelisches Diakoniekrankenhaus, Bremen.
authors.forename: J
authors.initials: J
authors.lastname: Grundmann
authors.forename: T
authors.initials: T
authors.lastname: Wolff
mesh_terms: D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008479:Mediastinal Neoplasms / Q000175:diagnosis*; D011879:Radiotherapy Dosage; D013945:Thymoma / Q000175:diagnosis* / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D013950:Thymus Gland / Q000473:pathology; D013953:Thymus Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D013997:Time Factors; D014057:Tomography, X-Ray Computed