title: Diffusion-weighted MR imaging in laryngeal and hypopharyngeal carcinoma: association between apparent diffusion coefficient and histologic findings.
abstract: OBJECTIVE
  To investigate the relationship between the histologic characteristics of head and neck squamous cell carcinoma and apparent diffusion coefficient (ADC) at diffusion-weighted magnetic resonance (MR) imaging.
  
  
  METHODS
  The institutional ethics committee approved this study and waived informed consent. In head and neck squamous cell carcinoma, local failure after chemotherapy and/or radiation therapy correlates with pretreatment ADC. However, the histopathologic basis of this correlation remains unclear. In this study, 16 patients with head and neck squamous cell carcinoma were enrolled (median age, 60 years; range, 49-78 years). Before undergoing total laryngectomy, patients underwent 1.5-T diffusion-weighted MR imaging. After resection, whole-mount hematoxylin-eosin-stained sections were registered to the MR images. Cellular density; nuclear, cytoplasmic, and stromal area; and nuclear-cytoplasmic ratio within the tumor were calculated by using image-based segmentation on four consecutive slices. Mean ADC of the corresponding tumor region was calculated. Spearman correlations between ADC and histologic characteristics were calculated.
  
  
  RESULTS
  ADC was significantly and inversely correlated with cell density (n = 16, r = -0.57, P = .02), nuclear area (n = 12, r = -0.64, P = .03), and nuclear-cytoplasmic ratio (n = 12, r = -0.77, P ≤ .01). ADC was significantly and positively correlated with percentage area of stroma (n = 12, r = 0.69, P = .01). Additionally, the percentage area of stroma was strongly interdependent with the percentage area of nuclei (n = 12, r = -0.97, P ≤ .01).
  
  
  CONCLUSIONS
  ADC was significantly correlated with cellularity, stromal component, and nuclear-cytoplasmic ratio. The positive correlation of ADC and stromal component suggests that the poor prognostic value of high pretreatment ADC might partly be attributed to the tumor-stroma component, a known predictor of local failure.
authors.affiliation: From the Department of Otorhinolaryngology-Head and Neck Surgery (J.P.D., L.M.J., W.G.), Rudolf Magnus Institute of Neuroscience (J.P.D., W.G.), Department of Radiotherapy (J.C.M., C.H.J.T., M.E.P.P.), Department of Radiology (F.A.P.), and Department of Pathology (N.K.), University Medical Center Utrecht, hp G05.129, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands.
authors.forename: Juliette P
authors.initials: JP
authors.lastname: Driessen
authors.forename: Joana
authors.initials: J
authors.lastname: Caldas-Magalhaes
authors.forename: Luuk M
authors.initials: LM
authors.lastname: Janssen
authors.forename: Frank A
authors.initials: FA
authors.lastname: Pameijer
authors.forename: Nina
authors.initials: N
authors.lastname: Kooij
authors.forename: Chris H J
authors.initials: CH
authors.lastname: Terhaard
authors.forename: Wilko
authors.initials: W
authors.lastname: Grolman
authors.forename: Marielle E P
authors.initials: ME
authors.lastname: Philippens
mesh_terms: D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000601:surgery; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000473:pathology* / Q000601:surgery; D007822:Laryngeal Neoplasms / Q000473:pathology* / Q000601:surgery; D007825:Laryngectomy; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010611:Pharyngectomy; D012189:Retrospective Studies