Review Article Diagnostic Imaging of Metastatic Cervical Lymph Nodes

The presence of lymph node metastasis in the neck in patients with cancer of the oral cavity or other head and neck regions is an important prognostic determinant in staging cancers and in planning radiotherapy of the cancer patients. We review recent advances in diagnostic imaging of metastatic lymph nodes in the neck of patients with extracranial head and neck squamous cell carcinoma, with the main emphasis on diagnostic performances of CT, sonography, and MR imaging

Diagnosis of Occlusal Tooth Wear Using 3D Imaging of Optical Coherence Tomography Ex Vivo

The aim of this study was to assess the utility of 3D imaging of optical coherence tomography (OCT) for the diagnosis of occlusal tooth wear ex vivo. Sixty-three extracted human molars with or without visible tooth wear were collected to take digital intraoral radiography and 3D OCT images. The degree of tooth wear was evaluated by 12 examiners and scored using 4-rank scale: 1-slight enamel wear; 2-distinct enamel wear; 3-tooth wear with slight dentin exposure; 4-tooth wear with distinct involvement of dentin. The degree of tooth wear was validated by the histological view of confocal laser scanning microscopy (CLSM). The sensitivity, specificity, and area under the curve (AUC) of receiver operating characteristic analysis were calculated. Diagnostic accuracy was compared with the agreement with CLSM observation using weighted kappa. The results were statistically analyzed at a significance level of alpha = 0.05. Three-dimensional OCT showed significantly higher sensitivity (p 0.05). Three-dimensional OCT could visualize and estimate the degree of tooth wear and detect the dentin exposure at the tooth wear surface accurately and reproducibly. Consequently, a new guideline for tooth wear assessment can be proposed using OCT

Simple and Reliable Determination of Intravoxel Incoherent Motion Parameters for the Differential Diagnosis of Head and Neck Tumors

Intravoxel incoherent motion (IVIM) imaging can characterize diffusion and perfusion of normal and diseased tissues, and IVIM parameters are authentically determined by using cumbersome least-squares method. We evaluated a simple technique for the determination of IVIM parameters using geometric analysis of the multiexponential signal decay curve as an alternative to the least-squares method for the diagnosis of head and neck tumors. Pure diffusion coefficients (D), microvascular volume fraction (f), perfusion-related incoherent microcirculation (D), and perfusion parameter that is heavily weighted towards extravascular space (P) were determined geometrically (Geo D, Geo f, and Geo P) or by least-squares method (Fit D, Fit f, and Fit D) in normal structures and 105 head and neck tumors. The IVIM parameters were compared for their levels and diagnostic abilities between the 2 techniques. The IVIM parameters were not able to determine in 14 tumors with the least-squares method alone and in 4 tumors with the geometric and least-squares methods. The geometric IVIM values were significantly different (p<0.001) from Fit values (+2±64% and 7±24% for D and f values, respectively). Geo D and Fit D differentiated between lymphomas and SCCs with similar efficacy (78% and 80% accuracy, respectively). Stepwise approaches using combinations of Geo D and Geo P, Geo D and Geo f, or Fit D and Fit Ddifferentiated between pleomorphic adenomas, Warthin tumors, and malignant salivary gland tumors with the same efficacy (91% accuracy = 21/ 23). However, a stepwise differentiation using Fit D and Fit f was less effective (83% accuracy = 19/23). Considering cumbersome procedures with the least squares method compared with the geometric method, we concluded that the geometric determination of IVIM parameters can be an alternative to least-squares method in the diagnosis of head and neck tumors

Extranodal spread of primary and secondary metastatic nodes: The dominant risk factor of survival in patients with head and neck squamous cell carcinoma

Extranodal spread (ENS) in patients with head and neck squamous cell carcinoma (HNSCC) can greatly influence the prognostic outcomes. However, the relative risks of ENS in the primary (1st) and secondary (2nd) metastatic nodes (mets) are not well documented. We retrospectively analyzed the hazard ratios (HRs) of ENS in the 1st and 2nd mets from 516 HNSCC patients who had undergone primary tumor excision. The impact of clinically and/or histologically confirmed ENS-positive mets on prognosis in terms of cancer-specific survival was analyzed. Cox proportional hazard regression analysis indicated that ENS-positive 1st met (adjusted HR = 3.15; 95% CI, 1.40?7.56; p = 0.006) and ENS-positive 2nd met (adjusted HR = 4.03; 95% CI, 1.41?16.96; p = 0.007) significantly and independently predicted poor prognosis; however, other variables including primary site, met size or numbers, and met location in the contralateral side of the primary lesion, did not. Cumulative incidence function and Cox analyses indicated that differences in ENS profiles of 1st and 2nd mets stratified HNSCC patients with varying risks of poor outcome; HRs relative to patients with ENS-positive 1st met (-)/ENS-positive 2nd met (-) were 4.02 (95% CI, 1.78?8.24; p = 0.002), 8.29 (95% CI, 4.58?14.76; p <0.001), and 25.80 (95% CI, 10.15?57.69; p <0.001) for patients with ENS-positive 1st met (+)/ENS-positive 2nd met (-), ENS-positive 1st met (-)/ENS-positive 2nd met (+), and ENS-positive 1st met (+)/ENS-positive 2nd met (+) patients, respectively. Kaplan-Meier analysis indicated that the 2nd met that appeared in the neck side with a history of 1st met and neck dissection had a higher risk of ENS than the 2nd met in the neck side without the history (p = 0.003). These results suggested that ENS is a dominant prognostic predictor of HNSCC patients, with double-positive ENS in the 1st and 2nd mets predicting the most devastating outcome

Salivary gland carcinoma: Prediction of cancer death risk based on apparent diffusion coefficient histogram profiles

We evaluated apparent diffusion coefficient (ADC) histogram parameters for predicting the outcomes of patients with salivary gland carcinoma. Diffusion-weighted MR imaging was performed in 20 patients with salivary gland carcinoma, and ADCs were determined using b-values of 500 and 1000 s/mm2. ADC histogram parameters (mean, median, percentage tumor area with distinctive ADC values [pADC], skewness, and kurtosis) were analyzed. The patients were followed for 5?136 months after primary surgery. The ADC histogram parameters and T (pT), N(pN), and M categories of the primary tumors were assessed for the prognostic importance using Cox proportional hazards models, logistic regression analysis, and receiver operating characteristic (ROC) analysis. Cohen’s d was determined for evaluating the importance of differences in the parameters between two patient groups with different outcomes. Six patients died of cancer (DOC) within 3 years after the primary surgery. Cox proportional hazards models indicated that ADC mean (95% CI = 0.494?0.977, p = 0.034), ADC median (95% CI = 0.511?0.997, p = 0.048), pADC with extremely low (<0.6 mm2/s) ADC (95% CI = 1.013?1.082, p = 0.007), kurtosis (95% CI = 1.166?7.420, p = 0.023), and pN classification (95% CI = 1.196?4.836, p = 0.012) were important factors of cancer death risk. ROC analyses indicated that the pADC <0.6 ×10?3 mm2/s was the best prognostic predictor (p <0.001; AUC = 0.929) among the ADC and TNM classification parameters that were significant in a univariate logistic regression analysis. Cohen’s d values between the DOC and survived patients for the ADC mean, ADC median, pADC with extremely low ADC, and kurtosis were 1.06, 1.04, 2.12, and 1.13, respectively. These results suggest that ADC histogram analysis may be helpful for predicting the outcomes of patients with salivary gland carcinoma

Whole-neck imaging for the screening of metastatic nodes

SummaryThe presence of lymph node metastasis in the neck of patients with head and neck cancer is an important prognostic determinant. Therefore, metastatic nodes should be effectively differentiated from non-metastatic reactive nodes, and a rapid and sensitive imaging technique is essential in staging cancers and planning surgery and chemo- and radiotherapy for cancer patients. MR imaging, positron emission tomography (PET), and CT may be useful in the surveillance of the neck disease in such patients. In this report, we reviewed the whole-neck imaging techniques for the effective screening of necks in patients with head and neck cancer

Univariate logistic regression and ROC analyses for the correlations between ADC parameters and cancer death in 20 patients with salivary gland carcinoma.

<p>Univariate logistic regression and ROC analyses for the correlations between ADC parameters and cancer death in 20 patients with salivary gland carcinoma.</p

Histological subtypes and ADC parameters of 20 salivary gland carcinomas.

<p>Histological subtypes and ADC parameters of 20 salivary gland carcinomas.</p