Dual-energy computed tomography in a multiparametric regression model for diagnosing lymph node metastases in pancreatic ductal adenocarcinoma.

OBJECTIVE: To investigate the diagnostic value of dual-energy computed tomography (DECT) quantitative parameters in the identification of regional lymph node metastasis in pancreatic ductal adenocarcinoma (PDAC). METHODS: This retrospective diagnostic study assessed 145 patients with pathologically confirmed pancreatic ductal adenocarcinoma from August 2016-October 2020. Quantitative parameters for targeted lymph nodes were measured using DECT, and all parameters were compared between benign and metastatic lymph nodes to determine their diagnostic value. A logistic regression model was constructed; the receiver operator characteristics curve was plotted; the area under the curve (AUC) was calculated to evaluate the diagnostic efficacy of each energy DECT parameter; and the DeLong test was used to compare AUC differences. Model evaluation was used for correlation analysis of each DECT parameter. RESULTS: Statistical differences in benign and metastatic lymph nodes were found for several parameters. Venous phase iodine density had the highest diagnostic efficacy as a single parameter, with AUC 0.949 [95% confidence interval (CI):0.915-0.972, threshold: 3.95], sensitivity 79.80%, specificity 96.00%, and accuracy 87.44%. Regression models with multiple parameters had the highest diagnostic efficacy, with AUC 0.992 (95% CI: 0.967-0.999), sensitivity 95.96%, specificity 96%, and accuracy 94.97%, which was higher than that for a single DECT parameter, and the difference was statistically significant. CONCLUSION: Among all DECT parameters for regional lymph node metastasis in PDAC, venous phase iodine density has the highest diagnostic efficacy as a single parameter, which is convenient for use in clinical settings, whereas a multiparametric regression model has higher diagnostic value compared with the single-parameter model.

Better specificity and less ischemia: three-dimensional reconstruction is superior to routine computed tomography angiography in navigation of super-selective clamping robot-assisted laparoscopic partial nephrectomy.

Background: Available technologies could be used to guide surgeons in controlling highly selective tumor-bearing arteries robot-assisted laparoscopic partial nephrectomy (RALPN). Methods: Patients undergoing RALPN (from September 2018 to January 2020) for intermediate-high complex renal tumor (R.E.N.A.L. score ≥7) who underwent abdominal computed tomography (CT) scan with angiography and hyper-accuracy 3-dimensional reconstruction (H3DR). All patients underwent high-resolution CT scan with angiography and H3DR with special software, based on which two kinds of highly selective arterial clamp protocols were made for each patient and analyzed independently by two urologists and two radiologists to confirm which renal arterial branch was supplying the tumor. We chose the optimized clamping protocol with the principle of the minimized ischemic regions. During the operation, meticulous microdissection and clip ligation of the specific vascular branch was guided by optimized protocol [H3DR or computed tomography angiography (CTA) reconstruction], according to the in vivo anatomy (identified by intraoperative ultrasound). Results: Of 82 patients, the minimum-ischemic regions planning completed rate (MIRPCR) of preoperative planning with H3DR (90.2%) was higher than that with CTA (34.1%) (P<0.01). H3DR identified 78 high-order arteries (70.3%), whereas CTA identified 33 (29.7%) high-order arteries (P<0.001). H3DR detected a more optimal blocking option in 51 cases that were either missed (n=13) or misclassified by CTA (n=38). A total of 18 cases (56.3%) were converted to H3DR-guided occurred in CTA-guided surgery [5 (10.0%) occurred in group H3DR to CTA, P<0.01]. Moreover, in the CTA-guided group, the separation of renal hilum was avoided in 14 of 19 (73.7%) cases, whereas in the H3DR-guided group, it was avoided in 60 of 63 (95.3%) cases. Conclusions: For patients undergoing RALPN, H3DR-guided surgery compared with standard CTA-guided surgery has higher accuracy and feasibility in controlling arterial branches supplying the tumor and intraoperative surgical navigation. Additionally, it reduces the ischemic lesion area and simplifies vascular isolation steps, thus decreasing procedural difficulty.

Deep learning radiomics of dual-energy computed tomography for predicting lymph node metastases of pancreatic ductal adenocarcinoma.

PURPOSE: Diagnosis of lymph node metastasis (LNM) is critical for patients with pancreatic ductal adenocarcinoma (PDAC). We aimed to build deep learning radiomics (DLR) models of dual-energy computed tomography (DECT) to classify LNM status of PDAC and to stratify the overall survival before treatment. METHODS: From August 2016 to October 2020, 148 PDAC patients underwent regional lymph node dissection and scanned preoperatively DECT were enrolled. The virtual monoenergetic image at 40 keV was reconstructed from 100 and 150 keV of DECT. By setting January 1, 2021, as the cut-off date, 113 patients were assigned into the primary set, and 35 were in the test set. DLR models using VMI 40 keV, 100 keV, 150 keV, and 100 + 150 keV images were developed and compared. The best model was integrated with key clinical features selected by multivariate Cox regression analysis to achieve the most accurate prediction. RESULTS: DLR based on 100 + 150 keV DECT yields the best performance in predicting LNM status with the AUC of 0.87 (95% confidence interval [CI]: 0.85-0.89) in the test cohort. After integrating key clinical features (CT-reported T stage, LN status, glutamyl transpeptadase, and glucose), the AUC was improved to 0.92 (95% CI: 0.91-0.94). Patients at high risk of LNM portended significantly worse overall survival than those at low risk after surgery (P = 0.012). CONCLUSIONS: The DLR model showed outstanding performance for predicting LNM in PADC and hold promise of improving clinical decision-making.

Dual-source dual-energy thin-section CT combined with small field of view technique for small lymph node in thyroid cancer: a retrospective diagnostic study.

BACKGROUND: To evaluate the diagnostic performance of quantitative spectral parameters derived from dual-source dual-energy CT at small field of view (FOV) for small lymph node metastasis in thyroid cancer. METHODS: This was a retrospective diagnostic study. From 2016 to 2019, 280 patients with thyroid disease underwent thin-section dual-source dual-energy thyroid CT and thyroid surgery. The data of patients with lymph nodes having a short diameter of 2-6 mm was analyzed. The quantitative dual-energy CT parameters of targeted lymph nodes were measured, and all parameters between metastatic and non-metastatic lymph nodes were compared. These parameters were then fitted to univariable and multivariable binary logistic regression models. The diagnostic role of spectral parameters was analyzed by receiver operating characteristic (ROC) curves and compared with the McNemar test. Small FOV CT images and a mathematical model were used to judge the status of lymph nodes respectively, and then compared with the golden criterion-pathological diagnosis. The cut-off value of the model was 0.4419, with a sensitivity of 90.2% and a specificity of 92.7%. RESULTS: Of the 216 lymph nodes investigated in this study, 52.3% and 23.6% had a short diameter of 2-3 and 4 mm, respectively. Multiple quantitative CT parameters were significantly different between benign and malignant lymph nodes, and binary regression analysis was performed. The mathematical model was: p=ey/(1+ ey), y=-23.119+0.033× precontrast electron cloud density +0.076× arterial phase normalized iodine concentration +2.156× arterial phase normalized effective atomic number -0.540× venous phase slope of the spectral Hounsfield unit curve +1.676× venous phase iodine concentration. This parameter model had an AUC of 92%, with good discrimination and consistency, and the diagnostic accuracy was 90.3%. The diagnostic accuracy of the CT image model was 43.1%, and for lymph nodes with a short-diameter of 2-3 mm, the diagnostic accuracy was 22.1%. CONCLUSIONS: The parameter model showed higher diagnostic accuracy than the CT image model for diagnosing small lymph node metastasis in thyroid cancer, and quantitative dual-energy CT parameters were very useful for small lymph nodes that were difficult to be diagnosed only on conventional CT images. TRIAL REGISTRATION: This study is retrospectively registered, and we have registered a prospective study (Registration number: ChiCTR2000035195; http://www.chictr.org.cn).

Assessment in the Survival Outcome After Transarterial Chemoembolization Combined with Cryoablation for Hepatocellular Carcinoma (Diameter > 4cm) Based on the Albumin-Bilirubin Grade and Platelet-Albumin-Bilirubin grade: A Preliminary Study.

OBJECTIVE: Based on the albumin-bilirubin (ALBI) and platelet-albumin-bilirubin (PALBI) grade to assess the long-term outcomes of patients with large hepatocellular carcinoma (HCC) after transarterial chemoembolization combined with cryoablation (TACE-CRA). MATERIALS AND METHODS: We studied 86 patients with HCC nodules (up to 3 HCCs with maximum diameters of 4.1-12.0 cm) who subsequently underwent TACE-CRA from July 2007 to August 2018. The overall survival (OS) was compared between groups classified by ALBI and PALBI grade. Baseline characteristics were collected to identify the risk factors for determination of poor OS after TACE-CRA. The prognostic performances of CTP class, ALBI and PALBI grade were compared. RESULTS: After a median follow-up time of 33.8 months, 41 patients had died. The cumulative1-, 3- and 5-year OS rates were 74.5%, 38.0% and 29.3%, respectively. Stratified according to ALBI grade, the cumulative 3- and 5-year OS rates were 41.2% and 41.2% in grade 1, respectively, and 20.9% and 9.8% in grades 2-3, respectively (P < 0.001). Stratified according to PALBI grade, the cumulative 3- and 5-year OS rates were 41.2% and 37.5% in grade 1, respectively, and 36.3% and 21.2% in grades 2-3, respectively (P = 0.002). Multivariate analysis results showed that older age, and ALBI grade 2-3 were associated with overall mortality. ALBI grade demonstrated significantly greater area under the curve values than CTP class and PALBI in predicting 1-, 3- and 5-year OS. CONCLUSION: ALBI grade offers accurate prediction of long-term outcome for patients with HCC (diameter > 4 cm) after TACE-CRA.

Percutaneous microwave ablation versus surgical resection for ovarian cancer liver metastasis.

Objective: To compare the oncological outcomes between microwave ablation (MWA) and surgical resection (SR) in patients with ovarian cancer liver metastasis (OCLM).Materials and methods: In this retrospective study, a total of 29 female patients (mean age, 47.8 ± 12.9 years; range, 21-65 years) diagnosed with forty-three OCLM nodules between September 2008 and July 2016 were included. All patients with ovarian cancer received chemotherapy and cytoreductive surgery (CRS). Fifteen patients with 22 nodules underwent MWA, and 14 patients with 21 nodules underwent SR. Overall survival (OS), local tumor recurrence-free survival (LTRS), and operation-related parameters were compared between the two groups. Multivariate analyses were performed on clinicopathological variables to identify factors affecting OS and LTRS.Results: The median follow-up time was 70.2 months (range, 12.1-107.2 months). Fourteen patients died during this period. The 1-, 3-, and 5-year OS and LTRS rates after MWA were comparable to those after SR (p = .198 and p = .889, respectively). Compared with the SR group, the MWA group had a shorter surgical time (p < .001), less estimated blood loss (p < .001), shorter postoperative hospitalization (p < .001) and fewer costs (p = .015). The multivariate analysis showed that old age (p = .001) was a predictor of poor OS and that intrahepatic tumor size (p = .005) and intrahepatic tumor number (p = .001) were predictors of poor LTRS.Conclusion: Percutaneous MWA had comparable oncologic outcomes with those of SR and could be a safe and effective treatment for OCLM.

Paranasal sinus invasion suggested T4 classification of patients of nasopharyngeal carcinoma: A two-center retrospective investigation.

BACKGROUND: To investigate the prognostic significance of paranasal sinus invasion in nasopharyngeal carcinoma (NPC) patients. METHODS: Patients with NPC after intensity-modulated radiotherapy from 2010 to 2013 were identified (n = 1225). Clinical features and magnetic resonance images were analyzed. RESULTS: Paranasal sinus invasion was identified in 182/1225 patients (14.9%). Multivariate analysis showed that paranasal sinus invasion was an independent factor for overall survival, progression-free survival, distant metastasis-free survival, and local recurrence-free survival (P < .05 for all). T3 NPC patients with paranasal sinus invasion had a poorer prognosis than those without (P < .05), and there was no significant survival difference compared with T4 patients, regardless of involvement of inner structures (P > .05 for all). Upgrading NPC with paranasal sinus invasion to T4 disease achieved better predictive abilities. CONCLUSIONS: Paranasal sinus invasion is an independent prognostic factor for NPC. It may be appropriate to upgrade the T classification.

[Environmental radiation dose monitor after 125I radioactive seed implantation].

BACKGROUND & OBJECTIVE: Medical imaging-guided 125I radioactive seed implantation is a new method of mini-invasive therapy. As a component of combined therapy for malignant tumors, 125I implantation has benefits of minimal invasion, accurate position fixing, and certain clinical effects, and has been widely applied to treat tumors at present. Also the environmental phototoxis and radiation protection have been highly regarded. This study was to investigate the environmental radiation dose monitor after 125I radioactive seed implantation. METHODS: From Oct. 2004 to Dec. 2005, 20 patients with malignant tumors were randomly selected in this study after 125I radioactive seed implantation. Environmental radiation dose was detected right after operation and 2, 4 and 6 months later with gamma-ray equipment. RESULTS: With the increase of the distance from radioactive source, the radiation dose decreased quickly. The detected dose was close to a natural background radiation dose at a distance of 50 cm from radioactive source. With time passing, the environmental radiation dose was attenuated and the detected dose was close to natural background after 6 months. CONCLUSIONS: Addition to the isolation and shielding protection before and after 125I radioactive seed implantation, distance protection and time protection should be considered. With necessary strict protection, 125I implantation is safe to patients and environment.