Preliminary Exploration on the Value of Shear Wave Elastography in Evaluating the Effectiveness of Microwave Ablation on Hepatic Malignancies.

ABSTRACT: Shear wave elastography (SWE) is a new type of ultrasonic elastography that can quantitatively assess the elasticity and stiffness of tissues. This study aimed to investigate the value of SWE in evaluating the effectiveness of microwave ablation in hepatic malignancies. A total of 24 patients (including 30 lesions) with liver malignancies receiving microwave ablation treatment at the Cancer Hospital of Guangzhou Medical University from April 2018 to January 2019 were enrolled. The elastography was performed within 1 week before and after ablation. The SWE values in the central zone, the marginal zone of the lesion, and peripheral liver parenchyma were collected and analyzed. Before ablation, the mean of SWE value was 65.80 ± 13.37 kPa for the central zone of the tumor and 39.93 ± 7.87 kPa for the marginal zone, both of which were significantly greater than that for the perinatal liver parenchyma (12.85 ± 2.67 kPa, both P < 0.05). In the central and marginal zone of the lesions, the SWE value was significantly elevated after ablation (both P < 0.001) but not in the peripheral liver parenchyma (P = 0.444). Receiver operating characteristic curve analysis showed that the cutoff value for ablation in the marginal zone was 53.87 kPa, suggesting that an SWE exceeding 53.87 kPa is an index guaranteeing the ablation effectiveness. These results suggested that SWE has the potential to be used in evaluating the effectiveness of microwave ablation in liver cancers.

Evaluation of Microwave Ablation Efficacy by Strain Elastography and Shear Wave Elastography in ex Vivo Porcine Liver.

The aim of this study was to evaluate the efficacy of microwave ablation by ultrasound (US), strain elastography (SE) and shear-wave elastography (SWE). An ex vivo model of porcine liver was adopted. According to ablation power and duration, 30 samples were divided into three groups: group 1 (45 W, 30 s), group 2 (45 W, 15 s) and group 3 (30 W, 30 s). US was used to measure the largest transverse diameter (D1), vertical diameter (D2) and anteroposterior diameter (D3) of the ablated area. SE was used to measure the largest transverse diameter (SEL1), vertical diameter (SEL2) and anteroposterior diameter (SEL3). The actual size of the ablated area was measured as the largest transverse diameter (L1), vertical diameter (L2) and anteroposterior diameter (L3). SWE values and temperatures were measured in the central lesion (region a), marginal area (region b) and unablated area (region c). At 1 h post-ablation, the values measured by US (D1, D2, D3) were all significantly smaller than the ablated area (L1, L2, L3) in all three groups. Except for SEL2 in group 1, there was no significant difference in the results between SEL and L among the three groups. All SWE results were significantly higher post-ablation than pre-ablation in the central lesion (region a) and marginal area (region b, all p values <0.05). In regions a, b and c, the temperatures measured immediately and 5 min post-ablation were all higher than that measured pre-ablation. These results suggest that SE and SWE can be used to evaluate the ablation efficacy of liver tissue.

Development and validation of nomograms to accurately predict risk of recurrence for patients with laryngeal squamous cell carcinoma: Cohort study.

BACKGROUND: Recurrence is still major obstacle to long-term survival in laryngeal squamous cell carcinoma (LSCC). We aimed to establish and validate a nomogram to precisely predict recurrence probability in patients with LSCC. METHODS: A total of 283 consecutive patients with LSCC received curative-intend surgery between 2011 and 2014 at were enrolled in this study. Subsequently, 283 LSCC patients were randomly assigned to a training cohort (N = 171) and a validation cohort (N = 112) in a 3:2 ratio. According to the results of multivariable Cox regression analysis in the training cohort, we developed a nomogram. The predictive accuracy and discriminative ability of the nomogram were evaluated by calibration curve and concordance index (C-index), and compared with TNM stage system by C-index, receiver operating characteristic (ROC) analysis. Decision curve analysis (DCA) was performed to estimate clinical value of our nomogram. RESULTS: Six independent factors rooted in multivariable analysis of the training cohort to predict recurrence were age, tumor site, smoking, alcohol, N stage and hemoglobin, which were all integrated into the nomogram. The calibration curve for the probability of recurrence presented that the nomogram-based predictions were in good correspondence with actual observations. The C-index of the nomogram was 0.81 (0.75-0.88), and the area under curve (AUC) of nomogram in predicting recurrence free survival (RFS) was 0.894, which were significantly better than traditional TNM stage. Decision curve analysis further affirmed that our nomogram had a larger net benefit than TNM stage. The results were confirmed in the validation cohort. CONCLUSION: A risk prediction nomogram for patients with LSCC, incorporating readily assessable clinicopathologic variables, generates more accurate estimations of the recurrence probability when compared TNM stage alone, but still needs additional data before being used in clinical implications.