title: MRI appearances of stage IE/IIE extranodal NK/T-cell lymphoma, nasal type, in the upper aerodigestive tract.
abstract: BACKGROUND
  The clinical symptoms of NK/T-cell lymphoma at presentation are nonspecific and may mimic those of other benign nasal diseases such as rhinitis and nasal polypus. However, radiologic studies regarding this aggressive clinical course entity are limited.
  
  
  OBJECTIVE
  To review 123 newly diagnosed MRI appearances in patients with extra-nodal NK/T-cell lymphoma, nasal type, in a large cohort and determine the characteristic imaging findings.
  
  
  METHODS
  We investigated the magnetic resonance imaging (MRI) findings of patients with newly diagnosed stage IE/IIE extranodal NK/T-cell lymphoma, nasal type, in the upper aerodigestive tract.
  
  
  RESULTS
  Most nasal cavity patients (63.4%) showed extra nasal cavity involvements. The polypoid pattern was most frequently seen (55.3%), followed by the infiltrative (27.6%) and combined (17.1%) patterns. The polypoid pattern tended to develop in the nasal cavity group, while the infiltration pattern was more common in the non-nasal cavity group (63.4% vs. 60.0%, p < 0.001). Homogeneous iso-intensity was seen in 97.6%, 88.6% and 56.1% of cases on T1-, T2-weighted images and post-contrast images, respectively. Bone destruction and necrosis were observed in 44.7% and 56.3% of patients. Both tumour necrosis and bone destruction were related to tumour size (p = 0.008, 0.001). Only 12.2% of patients had cervical lymphadenopathy Multi-region involvement, irregular growth pattern, predisposition to necrosis and bone destruction, and little lymphadenopathy are valuable for diagnosis and can be used to differentiate these tumours from other malignant tumours.
  
  
  CONCLUSIONS
  Our large cohort study of MRI of NK/T cell lymphoma, nasal type, revealed the features of this lymphoma on MRI including some radiologic signs never reported earlier; these findings are invaluable for early diagnosis and may aid future studies aiming to predict the prognosis and response to therapy.
authors.affiliation: Department of Radiology, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China. cjr.guyajia@vip.163.com  
authors.forename: Y
authors.initials: Y
authors.lastname: Gu
authors.forename: B
authors.initials: B
authors.lastname: Wu
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: Y
authors.initials: Y
authors.lastname: Guo
authors.forename: W
authors.initials: W
authors.lastname: Peng
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000473:pathology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D054391:Lymphoma, Extranodal NK-T-Cell / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009333:Neck; D009367:Neoplasm Staging; D009669:Nose Neoplasms / Q000473:pathology*; D012189:Retrospective Studies; D055815:Young Adult