title: Diffusion-Weighted Imaging of Nasopharyngeal Carcinoma: Can Pretreatment DWI Predict Local Failure Based on Long-Term Outcome?
abstract: Pretreatment prediction of patients with nasopharyngeal carcinoma who will fail conventional treatment would potentially allow these patients to undergo more intensive treatment or closer posttreatment monitoring. The aim of the study was to determine the ability of pretreatment DWI to predict local failure in patients with nasopharyngeal carcinoma based on long-term clinical outcome.
  
  
  
  One hundred fifty-eight patients with pretreatment DWI underwent analysis of the primary tumor to obtain the ADC mean, ADC skewness, ADC kurtosis, volume, and T-stage. Univariate and multivariate analyses using logistic regression were performed to compare the ADC parameters, volume, T-stage, and patient age in primary tumors with local failure and those with local control, by using a minimum of 5-year follow-up to confirm local control.
  
  
  
  Local control was achieved in 131/158 (83%) patients (range, 60.3-117.7 months) and local failure occurred in 27/158 (17%) patients (range, 5.2-79.8 months). Compared with tumors with local control, those with local failure showed a significantly lower ADC skewness (ADC values with the greatest frequencies were shifted away from the lower ADC range) (P = .006) and lower ADC kurtosis (curve peak broader) (P = .024). The ADC skewness remained significant on multivariate analysis (P = .044). There was a trend toward higher tumor volumes in local failure, but the volume, together with T-stage and ADC mean, were not significantly different between the 2 groups.
  
  
  
  Pretreatment DWI of primary tumors found that the skewness of the ADC distribution curve was a predictor of local failure in patients with nasopharyngeal carcinoma, based on long-term clinical outcome.
authors.affiliation: From the Departments of Imaging and Interventional Radiology (B.K.H.L., A.D.K., K.S.B., A.T.A., Q.Y.A.).
authors.forename: B K H
authors.identifier: 0000-0003-3836-8196
authors.initials: BK
authors.lastname: Law
authors.affiliation: From the Departments of Imaging and Interventional Radiology (B.K.H.L., A.D.K., K.S.B., A.T.A., Q.Y.A.) king2015@cuhk.edu.hk.
authors.forename: A D
authors.identifier: 0000-0002-5280-8349
authors.initials: AD
authors.lastname: King
authors.affiliation: From the Departments of Imaging and Interventional Radiology (B.K.H.L., A.D.K., K.S.B., A.T.A., Q.Y.A.).
authors.forename: K S
authors.identifier: 0000-0001-9388-9416
authors.initials: KS
authors.lastname: Bhatia
authors.affiliation: From the Departments of Imaging and Interventional Radiology (B.K.H.L., A.D.K., K.S.B., A.T.A., Q.Y.A.).
authors.forename: A T
authors.identifier: 0000-0002-0726-5402
authors.initials: AT
authors.lastname: Ahuja
authors.affiliation: Clinical Oncology (M.K.M.K., B.B.M., F.K.F.M., D.K.W.Y.), The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., China.
authors.forename: M K M
authors.identifier: 0000-0002-7681-6159
authors.initials: MK
authors.lastname: Kam
authors.affiliation: Clinical Oncology (M.K.M.K., B.B.M., F.K.F.M., D.K.W.Y.), The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., China.
authors.forename: B B
authors.identifier: 0000-0003-4802-1102
authors.initials: BB
authors.lastname: Ma
authors.affiliation: From the Departments of Imaging and Interventional Radiology (B.K.H.L., A.D.K., K.S.B., A.T.A., Q.Y.A.).
authors.forename: Q Y
authors.identifier: 0000-0002-1155-4389
authors.initials: QY
authors.lastname: Ai
authors.affiliation: Clinical Oncology (M.K.M.K., B.B.M., F.K.F.M., D.K.W.Y.), The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., China.
authors.forename: F K F
authors.identifier: 0000-0002-0566-3212
authors.initials: FK
authors.lastname: Mo
authors.affiliation: Medical Physics and Research Department (J.Y.), Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong S.A.R., China.
authors.forename: J
authors.identifier: 0000-0001-8112-3608
authors.initials: J
authors.lastname: Yuan
authors.affiliation: Clinical Oncology (M.K.M.K., B.B.M., F.K.F.M., D.K.W.Y.), The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., China.
authors.forename: D K W
authors.identifier: 0000-0002-2410-6761
authors.initials: DK
authors.lastname: Yeung
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000601:surgery*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D023381:Endpoint Determination; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D011237:Predictive Value of Tests; D017211:Treatment Failure; D016896:Treatment Outcome