title: Nasopharyngeal carcinoma: correlation of apparent diffusion coefficient value with prognostic parameters.
abstract: OBJECTIVE
  The aim of this study was to correlate the apparent diffusion coefficient (ADC) value with the prognostic parameters of nasopharyngeal carcinoma (NPC).
  
  
  METHODS
  This was a prospective study conducted on 30 consecutive patients (19 men, 11 women; mean age 61 years) with NPC. Patients underwent diffusion-weighted magnetic resonance (DW-MR) singleshot echoplanar imaging at 1.5 Tesla. NPC ADC value was correlated with pathological tumour type, pathological tumour grade, tumour volume and nodal status.
  
  
  RESULTS
  Mean NPC ADC value was 0.99 ± 0.11 × 10(-3)mm(2)/s. ADC values of well-differentiated and moderately differentiated tumours differed significantly (p=0.005) from those of poorly differentiated and undifferentiated NPC. There was also a significant difference in ADC value among small, medium and large tumour volume (p=0.03). ADC value was also significantly lower (p=0.003) when metastatic cervical lymph nodes were present. ADC value correlated inversely with tumour volume (r=-0.799, p=0.03).
  
  
  CONCLUSIONS
  ADC value can be considered a noninvasive prognostic parameter that correlates well with prognostic parameters of NPC.
authors.affiliation: Department of Radiology, Mansoura Faculty of Medicine, Mansoura 13351, Egypt. arazek@mans.edu.eg
authors.forename: Ahmed Abdel Khalek
authors.initials: AA
authors.lastname: Abdel Razek
authors.forename: Elsharawey
authors.initials: E
authors.lastname: Kamal
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D017352:Echo-Planar Imaging; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*; D060787:Neoplasm Grading; D011379:Prognosis; D011446:Prospective Studies; D047368:Tumor Burden
chemical_list: D003287:Contrast Media