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Intravoxel incoherent motion (IVIM) imaging is increasingly applied in the assessment of head and neck cancer (HNC). Our purpose was to determine the diagnostic and prognostic performance of IVIM in HNC by performing a critical review of the literature. Pubmed and EMBASE were searched until May 2016. Study and patients characteristics, imaging protocol and diagnostic or prognostic outcomes were extracted by 2 independent reviewers. The studied IVIM parameters were diffusion coefficient (D), pseudodiffusion coefficient (D∗), and perfusion fraction (f). We included 10 diagnostic studies, 5 prognostic studies and 2 studies assessing both. Studies were very heterogeneous in terms of applied b-values, imaging protocols, outcome measurements and reference standards; therefore we did not perform a meta-analysis. The most commonly used sequence was "spin-echo planar imaging". A median of 10.5 b-values (range, 3-17) were used. All but three studies included at least 4 b-values below b=200s/mm. By combining IVIM-parameters squamous cell carcinomas, lymphomas, malignant salivary gland tumors, Warthin's tumors and pleomorphic adenomas could be differentiated with a sensitivity of 85-87% and specificity of 80-100%. Low pre-treatment D or f and an increase in D during treatment were associated with a favorable response to treatment. D∗ appeared to be the parameter with the lowest prognostic value. Future research should focus on finding the optimal IVIM protocol, using uniformly accepted study methods and larger patient populations.

Background and purpose: In head and neck squamous cell carcinoma (HNSCC) (chemo)radiotherapy is increasingly used to preserve organ functionality. The purpose of this study was to identify predictive pretreatment DWI-and 18 F-FDG-PET/CT-parameters for treatment failure (TF), locoregional recurrence (LR) and death in HNSCC patients treated by (chemo)radiotherapy. Materials and methods: We retrospectively included 134 histologically proven HNSCC patients treated with (chemo)radiotherapy between 2012-2017. In 58 patients pre-treatment DWI and 18 F-FDG-PET/CT were performed, in 31 patients DWI only and in 45 patients 18 F-FDG-PET/CT only. Primary tumor (PT) and largest lymph node (LN) metastasis were quantitatively assessed for TF, LR and death. Multivariate analysis was performed for 18 F-FDG-PET/CT and DWI separately and thereafter combined. In patients with both imaging modalities, positive and negative predictive value in TF and differences in LR and death, were assessed. Results: Mean follow-up was 25.6 months (interquartile-range; 14.0-37.1 months). Predictors of treatment failure, corrected for TNM-stage and HPV-status, were SUV max-PT , ADC max-PT , total lesion glycolysis (TLG-LN), ADCp20-LN (P = 0.049, P = 0.024, P = 0.031, P = 0.047, respectively). TLG-PT was predictive for LR (P = 0.003). Metabolic active tumor volume (MATV-PT) (P = 0.003), ADC GTV-PT (P < 0.001), ADCSD (P = 0.048) were significant predictors for death. In patients with both imaging modalities SUV max-PT remained predictive for treatment failure (P = 0.049), TLG-LN for LR (P = 0.003) and ADC GTV-PT for death (P < 0.001). Higher predictive value for treatment failure was found for the combination of SUV max-PT and ADC max-PT , compared to either one separately. Conclusion: Both DWI-and 18 F-FDG-PET/CT-parameters appear to have predictive value for treatment failure, locoregional recurrence and death. Combining SUV max-PT and ADC max-PT resulted in better prediction of treatment failure compared to single parameter assessment.

).q RSNA, 2015 Purpose:To assess the correlation of intraocular retinoblastoma tumor size measured with magnetic resonance (MR) imaging in the prediction of histopathologically determined metastatic risk factors (postlaminar optic nerve invasion and massive choroidal invasion). Materials and Methods:The ethics committee approved this retrospective multicenter study with a waiver of informed consent. The study population included 370 consecutive patients with retinoblastoma (375 eyes) who underwent baseline MR imaging, followed by primary enucleation from 1993 through 2014. Tumor sizes (maximum diameter and volume) were measured independently by two observers and correlated with histopathologic risk factors. Receiver operating characteristic curves were used to analyze the diagnostic accuracy of tumor size, and areas under the curve were calculated. Logistic regression analysis was performed to evaluate potential confounders. Results:Receiver operating characteristic analysis of volume and diameter, respectively, yielded areas under the curve of 0. Conclusion:Intraocular tumor size shows a strong association with postlaminar optic nerve invasion and a moderate association with massive choroidal invasion. These findings provide diagnostic accuracy measures at different size cutoff levels, which could potentially be useful in a clinical setting, especially within the scope of the increasing use of eye-salvage treatment strategies.q RSNA, 2015

Pretreatment primary tumor volume and lymph node ADC1000 were significant independent predictors of DFS in HNSCC treated with (C)RT. DFS could be predicted from ADC-values acquired without and with including CE-T1WI in image analysis. The inclusion of CE-T1WI did not result in significant improvements in the predictive value of DWI. DWI without including CE-T1WI was highly reproducible.

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BACKGROUND AND PURPOSE:DWI is typically performed with EPI sequences in single-center studies. The purpose of this study was to determine the reproducibility of ADC values in the head and neck region in healthy subjects. In addition, the reproducibility of ADC values in different tissues was assessed to identify the most suitable reference tissue.

Objectives To assess (I) correlations between diffusion-weighted (DWI), intravoxel incoherent motion (IVIM), dynamic contrast-enhanced (DCE) MRI, and 18 F-FDG-PET/CT imaging parameters capturing tumor characteristics and (II) their predictive value of locoregional recurrence-free survival (LRFS) and overall survival (OS) in patients with head and neck squamous cell carcinoma (HNSCC) treated with (chemo)radiotherapy. Methods Between 2014 and 2018, patients with histopathologically proven HNSCC, planned for curative (chemo) radiotherapy, were prospectively included. Pretreatment clinical, anatomical, and functional imaging parameters (obtained by DWI/IVIM, DCE-MRI, and 18 F-FDG-PET/CT) were extracted for primary tumors (PT) and lymph node metastases. Correlations and differences between parameters were assessed. The predictive value of LRFS and OS was assessed, performing univariable, multivariable Cox and CoxBoost regression analyses. Results In total, 70 patients were included. Significant correlations between 18 F-FDG-PET parameters and DWI-/DCE volume parameters were found ( r > 0.442, p < 0.002). The combination of HPV (HR = 0.903), intoxications (HR = 1.065), PT ADC GTV (HR = 1.252), K trans (HR = 1.223), and V e (HR = 1.215) was predictive for LRFS (C-index = 0.546; p = 0.023). N-stage (HR = 1.058), HPV positivity (HR = 0.886), hypopharyngeal tumor location (HR = 1.111), ADC GTV (HR = 1.102), ADC mean (HR = 1.137), D* (HR = 0.862), K trans (HR = 1.106), V e (HR = 1.195), SUV max (HR = 1.094), and TLG (HR = 1.433) were predictive for OS (C-index = 0.664; p = 0.046). Conclusions Functional imaging parameters, performing DWI/IVIM, DCE-MRI, and 18 F-FDG-PET/CT, yielded complementary value in capturing tumor characteristics. More specific, intoxications, HPV-negative status, large tumor volume-related parameters, high permeability (K trans ), and high extravascular extracellular space (V e ) parameters were predictive for adverse locoregional recurrence-free survival and adverse overall survival. Low cellularity (high ADC) and high metabolism (high SUV) were additionally predictive for decreased overall survival. These different predictive factors added to estimated locoregional and overall survival. Key Points • Parameters of DWI/IVIM, DCE-MRI, and 18F-FDG-PET/CT were able to capture complementary tumor characteristics. • Multivariable analysis revealed that intoxications, HPV negativit...