title: Differential diagnosis of primary nasopharyngeal lymphoma and nasopharyngeal carcinoma focusing on CT, MRI, and PET/CT.
abstract: OBJECTIVE
  No study has done a comparative analysis of radiologic imaging findings between primary nasopharyngeal lymphoma (PNL) and nasopharyngeal carcinoma (NPC). The purpose of this study was to analyze computed tomography (CT) and magnetic resonance (MR) images and to evaluate the maximum standardized uptake value (SUV max) of positron emission tomography (PET)/CT between PNL and NPC, knowing the imaging features that distinguish PNL from NPC.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  University tertiary care facility.
  
  
  METHODS
  The authors analyzed the features on CT, MR imaging, and PET/CT of 16 patients diagnosed with PNL and 32 patients diagnosed with NPC histopathologically.
  
  
  RESULTS
  Patients with PNL had a larger tumor volume and showed symmetry of tumor shape than did patients with NPC. Patients with PNL also had higher tumor homogeneity than NPC patients on CT, T2-weighted, and postcontrast MR images. All PNL patients showed a high degree of enhancement without invasion to the adjacent deep structure. The involvement of the Waldeyer ring was significantly higher in PNL patients. Cervical and retropharyngeal lymphadenopathy and PET/CT SUV max showed no significant difference between PNL and NPC.
  
  
  CONCLUSIONS
  If the images present a bulky, symmetric nasopharyngeal mass with marked homogeneity, a high degree of enhancement, and a higher Waldeyer ring involvement combined with no invasion into the deep structure, PNL should be considered over NPC.
authors.affiliation: Department of Otorhinolaryngology and Medical Research Institute, Pusan National University School of Medicine, Busan, South Korea.
authors.forename: Kyu-Sup
authors.initials: KS
authors.lastname: Cho
authors.forename: Dae-Woon
authors.initials: DW
authors.lastname: Kang
authors.forename: Hak-Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Jong-Kil
authors.initials: JK
authors.lastname: Lee
authors.forename: Hwan-Jung
authors.initials: HJ
authors.lastname: Roh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000175:diagnosis* / Q000473:pathology; D002648:Child; D003287:Contrast Media; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D005260:Female; D019788:Fluorodeoxyglucose F18; D019786:Gadolinium DTPA; D006801:Humans; D008223:Lymphoma / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D019786:Gadolinium DTPA