title: Intravoxel incoherent motion imaging kinetics during chemoradiotherapy for human papillomavirus-associated squamous cell carcinoma of the oropharynx: preliminary results from a prospective pilot study.
abstract: This study aims to identify the temporal kinetics of intravoxel incoherent motion (IVIM) MRI in patients with human papillomavirus-associated (HPV+) oropharyngeal squamous cell carcinoma. Patients were enrolled under an Institutional Review Board (IRB)-approved protocol as part of an ongoing prospective clinical trial. All patients underwent two MRI studies: a baseline scan before chemoradiotherapy and a mid-treatment scan 3-4 weeks after treatment initiation. Parametric maps representing pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f) and apparent diffusion coefficient (ADC) were generated. The Mann-Whitney U-test was used to assess the temporal variation of IVIM metrics. Bayesian quadratic discriminant analysis (QDA) was used to evaluate the extent to which mid-treatment changes in IVIM metrics could be combined to predict sites that would achieve complete response (CR) in multivariate analysis. Thirty-one patients were included in the final analysis with 59 lesions. Pretreatment ADC and D values of the CR lesions (n = 19) were significantly lower than those of non-CR lesions (n = 33). Mid-treatment ADC, D and f values were significantly higher (p < 0.0001) than pretreatment values for all lesions. Each increase in normalized ΔADC of size 0.1 yielded a 1.45-fold increase in the odds of CR (p < 0.0003), each increase in normalized ΔD of size 0.1 yielded a 1.53-fold increase in the odds of CR (p < 0.0002), and each unit increase in Δf yielded a 2.29-fold increase in the odds of CR (p < 0.02). Combined ΔD and ΔADC were integrated into a multivariate prediction model and attained an AUC of 0.87 (95% confidence interval: 0.79, 0.96), as well as a sensitivity of 0.63, specificity of 0.85 and accuracy of 0.78, under leave-one-out cross-validation. In conclusion, IVIM is feasible and potentially useful in the prediction and assessment of the early response of HPV+ oropharyngeal squamous cell carcinoma to chemoradiotherapy.
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.|Department of Imaging Physic, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Yao
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Department of Imaging Physic, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: John D
authors.initials: JD
authors.lastname: Hazle
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.|Department of Clinical Oncology and Nuclear Medicine, Faculty of Medicine, University of Alexandria, Alexandria, Egypt.
authors.forename: Abdallah S R
authors.initials: AS
authors.lastname: Mohamed
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Frank
authors.affiliation: Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Hobbs
authors.affiliation: Department of Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Rivka R
authors.initials: RR
authors.lastname: Colen
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: G Brandon
authors.initials: GB
authors.lastname: Gunn
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Jihong
authors.initials: J
authors.lastname: Wang
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Division of Health Sciences & Technology, Massachusetts Institute of Technology, Charlestown, MA, USA.
authors.forename: Jayashree
authors.initials: J
authors.lastname: Kalpathy-Cramer
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Adam S
authors.initials: AS
authors.lastname: Garden
authors.affiliation: Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Stephen Y
authors.initials: SY
authors.lastname: Lai
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: David I
authors.initials: DI
authors.lastname: Rosenthal
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.|The University of Texas Graduate School of Biomedical Sciences, Houston, TX, USA.
authors.forename: Clifton D
authors.initials: CD
authors.lastname: Fuller
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*; D059248:Chemoradiotherapy / Q000379:methods*; D006258:Head and Neck Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007700:Kinetics; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009038:Motion; D009959:Oropharyngeal Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*; D017063:Outcome Assessment, Health Care / Q000379:methods; D027383:Papillomaviridae; D030361:Papillomavirus Infections / Q000150:complications / Q000175:diagnosis / Q000628:therapy; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000077195:Squamous Cell Carcinoma of Head and Neck; D016896:Treatment Outcome
keywords: HPV-associated oropharyngeal cancer; chemoradiotherapy; intravoxel incoherent motion imaging; response assessment