Dual-energy computed tomography could reliably differentiate metastatic from non-metastatic lymph nodes of less than 0.5 cm in patients with papillary thyroid carcinoma

Abstract

Background: Dual-energy computed tomography (DECT) has been widely applied to detect lymph node (LN) and lymph node metastasis (LNM) in various cancers, including papillary thyroid carcinoma (PTC). This study aimed to quantitatively evaluate metastatic cervical lymph nodes (LNs) <0.5 cm in patients with PTC using DECT, which has not been done in previous studies. Methods: Preoperative DECT data of patients with pathologically confirmed PTC were retrospectively collected and analyzed between May 2016 and June 2018. A total of 359 LNs from 52 patients were included. Diameter, iodine concentration (IC), normalized iodine concentration (NIC), and the slope of the energy spectrum curve (λ HU ) of LNs in the arterial and the venous phases were compared between metastatic and nonmetastatic LNs. The optimal parameters were obtained from the receiver operating characteristic (ROC) curves. The generalized estimation equation (GEE) model was used to evaluate independent diagnostic factors for LNM. Results: A total of 139 metastatic and 220 non-metastatic LNs were analyzed. There were statistical differences of quantitative parameters between the two groups (P value 0.000-0.007). The optimal parameter for diagnosing LNM was IC in the arterial phase, and its area under the curve (AUC), sensitivity, and specificity were 0.775, 71.9%, and 73.6%, respectively. When the three parameters of diameter, IC in the arterial phase, and NIC in the venous phase were combined, the prediction efficiency was better, and the AUC was 0.819. The GEE results showed that LNs located in level VIa [odds ratio (OR) 2.030, 95% confidence interval (CI): 1.134-3.634, P=0.017], VIb (OR 2.836, 95% CI: 1.597-5.038, P=0.000), diameter (OR 2.023, 95% CI: 1.158-3.532, P=0.013), IC in the arterial phase (OR 4.444, 95% CI: 2.808-7.035, P=0.000), and IC in the venous phase (OR 5.387, 95% CI: 3.449-8.413, P=0.000) were independent risk factors for LNM in patients with PTC. Conclusions: DECT had good diagnostic performance in the differentiation of cervical metastatic LNs <0.5 cm in patients with PTC.

Meta-analysis of the diagnostic value of dual-energy computed tomography parameters for lymph node metastasis in papillary thyroid cancer

“…After removal of the duplicates, 45 articles were left. After excluding meta-analyses, systematic reviews, animal experiments, and studies inconsistent with our topic and results, a total of 12 studies [11,[16][17][18][19][20][21][22][23][24][25][26]] with 1,522 PTC patients were nally included in our study. The ow chart of data collection is described in Fig.…”

“…In recent years, dual-energy CT has shown good application prospects in detecting LN metastasis in PTC [11]. However, there is still no meta-analysis to assess the diagnostic value of dual-energy CT parameters for LN metastasis in PTC.…”

“…Different from conventional CT scanning, dual-energy CT can not only obtain qualitative image features of LNs, but also generate iodine maps and energy spectrum curves by using X-rays of different energies to obtain more quantitative parameters [10]. Dual-energy CT has been widely used to detect LN and LN metastases in various cancers, including PTC [11,12]. A previous study demonstrated that quantitative dual-energy CT parameters were very useful for small LNs that were di cult to be diagnosed only on conventional CT images [13].…”

Iodine map histogram metrics in early-stage breast cancer: prediction of axillary lymph node metastasis status

“…In the current study, the ROIs were drawn on the solid portion of tumors based on 40 keV images, which can improve the accuracy of the segmentation. Although spectral CT selective quantification has been evaluated in other body regions ( 38 ), it has not been used in breast cancer for this particular purpose but instead for prediction of locoregional stage ( 39 ), nature of breast masses ( 40 ), and distant metastases ( 15 ).…”

Diagnostic accuracy of contrast-enhanced dual-energy computed tomography for detecting metastatic lymph nodes in patients with malignant tumors: a systematic review and meta-analysis

“…After a reading of the titles and abstracts of these 257 original studies, 202 papers were excluded. Then, full texts were read in detail, and a rescreening was performed based on the inclusion and exclusion criteria, resulting in a final sample of 16 eligible studies for inclusion in this meta-analysis (16,(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37). The flowchart outlining the screening process is shown in Figure 1.…”