The Role of Ultrasound and Shear-Wave Elastography in Evaluation of Cervical Lymph Nodes

Using ultrasound radiomics analysis to diagnose cervical lymph node metastasis in patients with nasopharyngeal carcinoma

OBJECTIVE

This study aimed to explore the clinical value of ultrasound radiomics analysis in the diagnosis of cervical lymph node metastasis (CLNM) in patients with nasopharyngeal carcinoma (NPC).

METHODS

A total of 205 cases of NPC CLNM and 284 cases of benign lymphadenopathy with pathologic diagnosis were retrospectively included. Grayscale ultrasound (US) images of the largest section of every lymph node underwent feature extraction. Feature selection was done by maximum relevance minimum redundancy (mRMR) algorithm and multivariate logistic least absolute shrinkage and selection operator (LASSO) regression. Logistic regression models were developed based on clinical features, radiomics features, and the combination of those features. The AUCs of models were analyzed by DeLong's test.

RESULTS

In the clinical model, lymph nodes in the upper neck, larger long axis, and unclear hilus were significant factors for CLNM (p < 0.001). MRMR and LASSO regression selected 7 significant features for the radiomics model from the 386 radiomics features extracted. In the validation dataset, the AUC value was 0.838 (0.776-0.901) in the clinical model, 0.810 (0.739-0.881) in the radiomics model, and 0.880 (0.826-0.933) in the combined model. There was not a significant difference between the AUCs of clinical models and radiomics models in both datasets. DeLong's test revealed a significantly larger AUC in the combined model than in the clinical model in both training (p = 0.049) and validation datasets (p = 0.027).

CONCLUSION

Ultrasound radiomics analysis has potential value in screening meaningful ultrasound features and improving the diagnostic efficiency of ultrasound in CLNM of patients with NPC.

KEY POINTS

• Radiomics analysis of gray-scale ultrasound images can be used to develop an effective radiomics model for the diagnosis of cervical lymph node metastasis in nasopharyngeal carcinoma patients. • Radiomics model combined with general ultrasound features performed better than the clinical model in differentiating cervical lymph node metastases from benign lymphadenopathy.

The Value of Shear Wave Elastography in the Diagnosis of Breast Cancer Axillary Lymph Node Metastasis and Its Correlation With Molecular Classification of Breast Masses

Objective

To explore the diagnostic value of shear wave elastography examination (SWE) on axillary node metastasis (ANM) in breast cancer, this study aimed to evaluate the correlation between the SWE features and different molecular types of breast cancer, and to check the elastic modulus differences among the molecular types.

Methods

Breast cancer patients from November 2020 to December 2021 were subjected to both conventional ultrasonic examination (CUE) and SWE before ultrasound-guided percutaneous biopsy or axillary lymph node dissection (ALND). We used the pathological results as the gold standard to draw the receiver operating characteristic (ROC) curve.

Results

SWE outperforms CUE, but their conjunctive use is the best option. No significant correlation was found between the elastic modulus values and the molecular types of breast cancer.

Conclusion

SWE can be used as an routine auxiliary method of CUE for ANM.

Efficacy of logistic regression model based on multiparametric ultrasound in assessment of cervical lymphadenopathy - a retrospective study

OBJECTIVES

To investigate whether a multiparametric ultrasound (MPUS) diagnostic model improves differential diagnosis of benign and malignant cervical lymph nodes.

METHODS

MPUS evaluation was performed on 87 lesions in 86 patients, and related characteristics and parameters of the patients and lesions were studied and logistic regression models based on the MPUS characteristics of cervical lymph nodes were built. A receiver operating characteristic curve and area under the curve (AUC) were built for the evaluation of diagnostic performances.

RESULTS

Of the 87 lesions in 86 patients, there were 31 benign and 56 malignant lesions. Regression models for Duplex ultrasound and MPUS were established. The Duplex ultrasound regression model showed a sensitivity, specificity, positive predictive value and negative predictive value of 94.4, 61.3, 86.3 and 80.9%, respectively. The predictive accuracy was 82.4%, and the AUC was 0.861. The MPUS regression model showed a sensitivity, specificity, positive predictive value and negative predictive value of 98.1, 61.3, 81.5 and 95.0%, respectively. The predictive accuracy was 84.7%, and the AUC was 0.894. The differences in AUCs between the Duplex ultrasound model and MPUS model, ultrasound model and ultrasonic elastography (UE), and Duplex ultrasound and UE were not significant (all p > 0.05); the differences in AUCs between the MPUS model and Duplex ultrasound, Duplex ultrasound model and Duplex ultrasound, and MPUS model and UE were significant (all p < 0.05).

CONCLUSIONS

The Duplex ultrasound and MPUS models achieve significantly higher diagnostic performance for differentiating between benign and malignant cervical lymph nodes.

Ultrasound Imaging in Dentistry: A Literature Overview

(1) Background: the frequency with which diagnostic tests are prescribed with exposure to ionizing radiation, a cause of biological damage, has been studied, and with much more attention, patients are subjected to these diagnostic tests for diagnosis and follow-up. This review aimed, given the recent developments of this technology, to evaluate the possible use of ultrasound in different branches of dentistry. The possibility of applying ionizing-radiation-free diagnostic exams in dentistry, overcoming the limits of this application, has led scientific research in this area to obtain interesting results that bode well for the future. (2) Methods: a search for articles on the application of ultrasounds in dentistry was performed using the PubMed electronic database. (3) Results: only 32 studies were included, and these clearly stated that this examination is widely usable and in great progress. (4) Conclusions: regarding the modern application techniques of this diagnostic test, it is essential to consider technological evolution as an objective to reduce the damage and side effects of necessary diagnostic tests. The use of ultrasound in dentistry can represent a valid radiation-free alternative, in certain contexts, to the other most used exams.

Shear wave velocity measurements obtained in different regions are repeatable for presumed normal canine lymph nodes: A pilot study

Shear wave elastography (SWE) has been applied as a noninvasive method for predicting regional lymph node (LN) metastases in human and veterinary patients. However, published studies describing standardized protocols and repeatability of this technique are currently lacking. The objective of this prospective, pilot, observer agreement study was to determine whether different shear wave velocity (SWV) measurements obtained in different regions of presumed normal canine LNs would be repeatable. Two imagers consecutively performed shear wave elastography of submandibular, superficial inguinal, and popliteal LNs in 10, clinically healthy adult dogs. Ten elastograms of each LN were acquired by each imager. In each adequate elastogram, three regions of interest (ROIs) were placed in the softest and stiffest region of the LN. Additionally, one ROI was drawn covering the entire LN. In each ROI, mean, median, and maximum SWVs were calculated. Mean values for the mean, median, and maximum SWVs varied from 2.33 to 3.10 m/s, 2.32 to 3.10 m/s, and 2.61 to 4.09 m/s, respectively. Intra- and interobserver agreements were acceptable. Superficial inguinal LNs demonstrated the highest intra- and interobserver agreement, followed by the popliteal and the submandibular LNs, respectively. Using the different measurements (mean, median, or maximum SWVs) had no significant effect on the intra- and interobserver variability, neither did the region (softest, stiffest, or entire LN). Findings indicated that all evaluated measurements and regions could be used to obtain reliable elastography data of presumed normal canine LNs. Clinical trials in dogs with cancer are necessary to compare SWVs of metastatic LNs with the reported SWVs and evaluate whether various measurements and regions can also be used in metastatic LNs.

Quantitative and Qualitative Approach for Shear Wave Elastography in Superficial Lymph Nodes

The diagnostic contribution of 2-D shear-wave elastography (SWE) in management of superficial lymph nodes (LNs) of any origin was evaluated in 222 patients referred for needle core biopsy. Each patient underwent conventional B-mode/Doppler ultrasound examinations (conventional ultrasound) and SWE. Quantitative SWE parameters and qualitative SWE map features were extracted. Carcinomas were found to be significantly stiffer than benign LNs (29.5 ± 32.3 kPa vs. 6.7 ± 12.3 kPa). Lymphomas exhibited intermediate stiffness (11.4 ± 5.2 kPa). Qualitative SWE analysis provided color patterns specific to histopathology (stiff rim, nodular and undetermined patterns related to malignancy and blue pattern to benignity). Adding SWE to conventional ultrasound improved the sensitivity of LN diagnosis (from 81.1% to 92.0%) but decreased its specificity (from 73.2% to 67.6%) because of the high prevalence of lymphomas compared with carcinomas. Inter-observer agreement for quantitative SWE was good (intra-class correlation coefficient = 0.82) as was inter-observer diagnostic agreement for qualitative SWE (κ = 0.65). LN location and histology type were found to influence the reported diagnostic performance of SWE.

Application of Transthoracic Shear Wave Elastography in Evaluating Subpleural Pulmonary Lesions

AIM

The objective of this research was to investigate the feasibility of transthoracic shear wave elastography in the differentiation of subpleural masses.

METHODS

Between December 2019 and November 2020,82 consecutive patients with radiographic evidence (including chest X ray and thoracic computed tomography CT) of single subpleural lesion enrolled in this research. The Young's modulus E (including E_mean and E_max) of each lesion was detected, and the Young's modulus E of malignant lesions were compared with those of benign ones. We made diagnoses according to the results of pathology or standard clinical course for at least 3 months. Receiver operating characteristic (ROC) analysis was plotted to determine the cut-off point by maximizing the Youden index.

RESULTS

The E_mean and E_max of the benign and malignant group was 34.68 ± 12.12 kPa vs. 53.82 ± 11.95 kPa (p < 0.001), 57.77 ± 14.45 kPa vs. 76.62 ± 17.04 kPa (p < 0.001). The ROC of E_mean showed that when the cut-off point was 43.8 kPa, the Youden index (0.53) for distinguishing benign and malignant tumors was the largest (sensitivity 80.4 %, specificity 72.2 %, AUC = 0.848, p < 0.0001). When the cut-off point recommended by E_max ROC was 73.5 kPa, the Youden index (0.44) for distinguishing benign and malignant tumors was the largest (sensitivity 76.1 %, specificity 66.7 %, AUC = 0.780, p < 0.0001).

CONCLUSIONS

This study demonstrated that we can employ transthoracic shear wave elastography as a valuable instrument in differentiating benign subpleural lesions from malign ones.

Targeting Mechanotransduction in Osteosarcoma: A Comparative Oncology Perspective

Mechanotransduction is the process in which cells can convert extracellular mechanical stimuli into biochemical changes within a cell. While this a normal process for physiological development and function in many organ systems, tumour cells can exploit this process to promote tumour progression. Here we summarise the current state of knowledge of mechanotransduction in osteosarcoma (OSA), the most common primary bone tumour, referencing both human and canine models and other similar mesenchymal malignancies (e.g., Ewing sarcoma). Specifically, we discuss the mechanical properties of OSA cells, the pathways that these cells utilise to respond to external mechanical cues, and mechanotransduction-targeting strategies tested in OSA so far. We point out gaps in the literature and propose avenues to address them. Understanding how the physical microenvironment influences cell signalling and behaviour will lead to the improved design of strategies to target the mechanical vulnerabilities of OSA cells.

Multimodal Ultrasound Including Virtual Touch Imaging Quantification for Differentiating Cervical Lymph Nodes

Defining the entity of cervical lymph nodes (LNs) is essential for the diagnosis and staging of head and neck malignancies. Virtual Touch imaging quantification (VTIQ) is a relatively new method of elastography that measures tissue stiffness quantitatively. A prospective study was conducted that included 108 patients (57 benign and 51 metastatic lymph nodes [MLNs]). Shear wave velocities (SWVs) were analyzed using VTIQ and were compared with the histopathological results. Both maximum and minimum SWVs within the LNs significantly differed between benign masses and MLNs (p < 0.001). Percentage areas of the node with SWVs >6 m/s and <3.5 m/s differed significantly (p < 0.001). Intralesional areas with SWVs ≤3.5 m/s of 0-29% (odds ratio: 93.7) and 30%-69% (odds ratio: 46.3) were predictive of malignant LNs as well as ill-defined tumor (odds ratio: 5.2). VTIQ can provide more information on the entity of cervical LNs.

The effect of regions-of-interest and elasticity modulus selection on differentiating benign and malignant cervical lymph nodes with shear wave elastography

OBJECTIVE

Imaging diagnosis of cervical lymphadenopathy has conventionally used ultrasonography. Shear wave elastography (SWE) is a recent ultrasound technological advancement that has shown promise in the important medical problem of differentiating between benign and malignant cervical lymph nodes based on quantitative measurements of elasticity modulus. However, widely varying elasticity modulus metrics and regions-of-interest (ROIs) were used in existing studies, leading to inconsistent findings and results that are hard to compare with each other.

METHODS

Using a large dataset of 264 cervical lymph nodes from 200 patients, we designed a study comparing three elasticity modulus metrics (Emax, Emean, and standard deviation-SD) with three different ROIs to evaluate the effect of such selections. The metric values were compared between the benign and malignant node groups. The different ROI and metric selections were also compared through receiver operating characteristics curve analysis.

RESULTS

For all ROIs, all metric values were significantly different between the two groups, indicting their diagnostic potential. This was confirmed by the ≥0.80 area under the curve (AUC) values achieved with these metrics. Different ROIs had no effect on Emax, whereas all ROIs achieved high performance at 0.88 AUC. For Emean, the smallest ROI focusing on the area of the highest elasticity achieved the best diagnostic performance. In contrast, the larger ROIs achieved higher performances for SD.

CONCLUSIONS

This study illustrated the effect of elasticity modulus and ROI selection on the diagnostic performance of SWE on cervical lymphadenopathy. These new findings help guide relevant future studies and clinical applications of this important quantitative imaging modality.

Incorporation of shear wave elastography into a prediction model in the assessment of cervical lymph nodes

Rationale and objectives

To assess the performance of shear wave elastography (SWE) and an extended model in predicting malignant cervical lymph nodes (LNs).

Materials and methods

109 patients who underwent ultrasound (US) and SWE before needle biopsy were enrolled. The optimal cutoff value of elasticity indices (EIs) was determined by receiver operating characteristic (ROC) curves. The c-statistic, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to compare extended model and traditional one.

Results

Malignant LNs had higher EIs than benign nodes (p < 0.001). The optimal cutoff point was 42 kilopascal, corresponding to 83.3% sensitivity, 64.7% specificity, and 68.8% overall accuracy. A multivariable logistic regression analysis confirmed that EI was an independent predictor for malignancy. The new extended prediction model had a positive NRI (0.96) and IDI (0.10) for predicting malignant neck LNs. Nevertheless, the c-statistic was not significantly different between the two models.

Conclusion

The parameter of SWE theoretically improve the model performance. However, its real clinical impact is minor, as the parameters of US-based model is already very robust. SWE can be considered as an adjunctive quantitative tool beyond conventional US examination.