A Pilot Study: N-Staging Assessment of Shear Wave Elastrography in Small Cervical Lymph Nodes for Nasopharyngeal Carcinoma

The diagnostic value of two-dimensional shear-wave elastography in identifying malignant lesions in lymph nodes: a prospective study

This study evaluates the diagnostic performance of two-dimensional shear wave elastography (2D-SWE) in differentiating between benign, metastatic lymph nodes (LNs) and lymphomas. From May 2022 to February 2023, a total of 137 patients who presented with unexplained LN enlargement were examined at the Ultrasound Medical Department of Union Hospital of Huazhong University of Science and Technology. The conventional ultrasound recorded the location, longitudinal diameter, transverse diameter, L/T ratio, blood supply mode, lymphatic hilum and 2D-SWE calculated the average elasticity (E) of LN. Histopathology was the diagnostic gold standard. A total of 124 patients with 159 superficial LNs were included (32 benign, 70 metastatic, 57 lymphoma). Malignant LNs had significantly higher E values than benign ones (49.38 ± 29.96 kPa vs. 25.00 ± 14.42 kPa, P < 0.001). When E > 25.46 kPa, the AUC, sensitivity, specificity, PPV, NPV and accuracy were 0.807, 0.787, 0.750, 0.926, 0.471 and 0.780, respectively, in identifying malignant LNs. For distinguishing benign LNs from lymphoma, the E cutoff was 25.03 kPa, with the AUC, sensitivity, specificity, PPV, NPV and accuracy of 0.727, 0.754, 0.719, 0.827, 0.622 and 0.742, respectively. To differentiate benign from metastatic LNs, an E cutoff of 36.97 kPa yielded an AUC, sensitivity, specificity, PPV, NPV and accuracy of 0.872, 0.757, 0.875, 0.930, 0.622 and 0.794, respectively. Comparing lymphoma and metastatic LNs, the E cutoff was 42.57 kPa. And the AUC, sensitivity, specificity, PPV, NPV and accuracy were 0.787, 0.700, 0.860, 0.860, 0.700 and 0.772, respectively. 2D-SWE parameter (the average elasticity) can effectively evaluate benign, metastatic LNs and lymphoma, which provides valuable information for preoperative evaluation of superficial LNs.

Quantitative parameter analysis of pretreatment dual-energy computed tomography in nasopharyngeal carcinoma cervical lymph node characteristics and prediction of radiotherapy sensitivity

BACKGROUND

Treatment efficacy may differ among patients with nasopharyngeal carcinoma (NPC) at similar tumor-node-metastasis stages. Moreover, end-of-treatment tumor regression is a reliable indicator of treatment sensitivity. This study aimed to investigate whether quantitative dual-energy computed tomography (DECT) parameters could predict sensitivity to neck-lymph node radiotherapy in patients with NPC.

METHODS

Overall, 388 lymph nodes were collected from 98 patients with NPC who underwent pretreatment DECT. The patients were divided into complete response (CR) and partial response (PR) groups. Clinical characteristics and quantitative DECT parameters were compared between the groups, and the optimal predictive ability of each parameter was determined using receiver operating characteristic (ROC) analysis. A nomogram prediction model was constructed and validated using univariate and binary logistic regression.

RESULTS

DECT parameters were higher in the CR group than in the PR group. The iodine concentration (IC), normalized IC, Mix-0.6, spectral Hounsfield unit curve slope, effective atomic number, and virtual monoenergetic images were significantly different between the groups. The area under the ROC curve of the DECT parameters was 0.73-0.77. Based on the binary logistic regression, a column chart was constructed using 10 predictive factors, including age, sex, N stage, maximum lymph node diameter, arterial phase NIC, venous phase NIC, λHU and spectral Hounsfield units at 70 keV. The area under the ROC curve value of the constructed model was 0.813, with a sensitivity and specificity of 85.6% and 81.3%, respectively.

CONCLUSION

Quantitative DECT parameters could effectively predict the sensitivity of NPC to radiotherapy. Therefore, DECT parameters and NPC clinical features can be combined to construct a nomogram with high predictive power and used as a clinical analytical tool.

Difference after radiotherapy observed in patients with nasopharyngeal carcinoma

To evaluate the shrinkage rate of small cervical lymph nodes (SCLNs) at different levels in patients with nasopharyngeal carcinoma (NPC) treated with radiotherapy retrospectively. 96 adult patients with NPC who underwent intensity-modulated radiotherapy (IMRT) at our institution were analyzed and followed-up. Evaluation of the response (shrinking rate) of SCLNs was determined by the bidimensional tumor area. Binary logistic regression was conducted to explore the risk factors associated with the shrinking rate of SCLNs. Of the 96 patients included in this study, 1,194 SCLNs were identified. Among the SCLNs, 28.6% were level IIb and 21.3% were level IIa. SCLNs at level IIa (96.1%), tended to have a response effect of no change (NC) with shrinking rate <50% (odds ratio [OR]=0.007; 95% CI: 0.003-0.021, P=5.287×10^-25). Conversely, the most proportionate share of SCLNs for shrinking rate ≥50% (complete response (CR) or partial response (PR)) was observed at level IIb (67.2%) (OR=6.104; 95% CI: 3.267-11.407, P=1.420×10^-8). There was no significant difference of shrinking rate between irradiation doses of 60Gy and 63Gy. Most SCLNs at level IIa were not shrunk after radiotherapy. The irradiation dose of SCLNs at level IIa should be not more than 60Gy to reduce side effects.

Quantitative Multiparametric Ultrasound (mpUS) in the Assessment of Inconclusive Cervical Lymph Nodes

Background: Enlarged cervical lymph nodes (CLN) are preferably examined by ultrasound (US) by using criteria such as size and echogenicity to assess benign and suspicious CLN, which should be histologically evaluated. This study aims to assess the differentiation of malign and benign CLN by using multiparametric US applications (mpUS). Methods: 101 patients received a standardized US protocol prior to surgical intervention using B-mode−US, shear-wave elastography (SWE) and contrast-enhanced ultrasound (CEUS). SWE was assessed by 2D real-time SWE conducting a minimum of five measurements, CEUS parameters were assessed with post-processing perfusion software. Histopathological confirmation served as the gold standard. Results: B-mode−US and SWE analysis of 104 CLN (36 benign, 68 malignant) showed a significant difference between benign and malignant lesions, presenting a larger long axis and higher tissue stiffness (both p < 0.001). Moreover, tissue stiffness assessed by SWE was significantly higher in CLN with regular B-mode−US criteria (Solbiati Index > 2 and short-axis < 1 cm, p < 0.001). No perfusion parameter on CEUS showed a significant differentiation between benign and malignant CLN. Discussion: As the only multiparametric parameter, SWE showed higher tissue stiffness in malignant CLN, also in subgroups with regular B-mode criteria. This fast and easy application may be a promising noninvasive tool to US examination to ameliorate the sonographic differentiation of inconclusive CLN.