Retrospective Evaluation and Significance of Neutrophil-to-Lymphocyte Ratio Prior to and 1 month Following Microwave Ablation of Hepatocellular Carcinoma.

PURPOSE: Neutrophil-to-lymphocyte ratio (NLR) recently demonstrated predictive value for hepatocellular carcinoma (HCC) recurrence after thermal ablation. Microwave ablation (MWA) has been shown to induce changes in the immune landscape after HCC treatment. This study aims at identifying predictors of local tumor progression (LTP) and post-treatment NLR kinetics after MWA. MATERIALS AND METHODS: Data from 108 consecutive patients who underwent percutaneous MWA of 119 HCCs with a 2450 Hz/100 W generator in two institutions from October 2014 to September 2021 were retrospectively reviewed. Forty-five HCCs (42 patients) met inclusion criteria for analysis (technique efficacy, pre- and post-treatment NLR availability, follow-up > 6 months, absence of complications). NLR was analyzed prior to therapy and at 1-month follow-up; difference between the two time points was defined as ΔNLR1stFU. RESULTS: After a median follow-up of 25 months, LTP occurred in 18 HCCs (40%) and 18 patients (42.9%). Multivariate competing risk regression comprising ΔNLR1stFU > 0, cirrhosis etiology and subcapsular location showed that the only independent predictor of LTP was ΔNLR1stFU > 0, on both a per-patient (HR = 2.7, p = 0.049) and per-tumor (HR = 2.8, p = 0.047) analysis. ΔNLR1stFU > 0 occurred in 24/42 patients (57.1%). In this subgroup, higher rates of female patients (p = 0.026), higher mean baseline NLR (p < 0.0001) and lower mean energy/size (p = 0.006) were observed. Upon ROC curve analysis, energy/size < 1414 J/mm predicted ΔNLR1stFU > 0 with 76% sensitivity and 70% specificity (AUC = 0.74). CONCLUSION: NLR increase after ablation was the only independent predictor of LTP, supporting the role of balance between systemic inflammation and immunity in recurrence after MWA. Ablation energy/tumor size predicted NLR increase, reinforcing the concept of immune ablation. LEVEL OF EVIDENCE: III.

Present Status of Thyroid Ablation in Europe: An International Survey among the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) Members.

AIM: To evaluate the effective spread of image-guided thermal ablation in thyroid gland and to characterize its current perceptions among European interventional radiologists. MATERIALS AND METHODS: A questionnaire with 29 multiple choice questions about thyroid ablation was sent as an E-blast to 4752 CIRSE members. Only those who completed the survey in all its parts were included in the study. RESULTS: 242/4752 (5.09%) participants (212 males and 30 females) completed and submitted the survey. A total of 160 subjects (66.1%) were familiar with any image-guided thermal ablations, but only 63 (26% of total population) usually perform thermal ablation for thyroid gland. Only 19.5% of the interviewed sample treats micropapillary thyroid tumours and the vast majority routinely uses radiofrequency ablation (84.4%). CONCLUSION: There is a significant mismatch between thyroid ablation as reported by the literature and the relatively low percentage of interventional radiology actively performing such procedure in Europe. A considerable effort is required by the Cardiovascular and Interventional Radiological Society of Europe to fill this lack.

The What, the Why, and the How of Liver Ablations: A Practical Guide for the Medical Oncologist.

Interventional oncology plays a major role within modern oncological patient management. Image-guided thermal ablation has been recognized as a successful local therapeutic option in patients with primary and secondary malignant liver diseases, as also recalled by the recent European Society of Medical Oncology (ESMO) guidelines on colorectal metastases. As image-guided treatments may be as effective as surgery in selected patients with liver lesions, the clinical oncologist should be familiar with the indications, risks, and technical aspects of liver ablation in order to provide their patients with the best outcomes. This article provides a broad overview of the most commonly used ablation techniques and highlights the most relevant technical aspects such as the ideal setting in the operating theatre; which image-guided methods are available, including the growing application of fusion imaging; or contrast-enhanced ultrasound for guiding/monitoring the procedure. A further aim is to expand the knowledge among medical oncologists about liver ablation procedures and to provide insights into the future perspectives of percutaneous minimally invasive procedures in the liver.

A critical appraisal of the quality of guidelines for radiation protection in interventional radiology using the AGREE II tool: A EuroAIM initiative.

PURPOSE: To systematically review and assess the methodological quality of guidelines for radiation protection in interventional radiology. MATERIALS AND METHODS: On April 15th, 2021, a systematic search for guidelines on radiation protection in interventional radiology was performed using MEDLINE, EMBASE, National Guideline Clearinghouse, and National Institute for Health and Clinical Excellence databases. Among retrieved guidelines, we then excluded those not primarily focused on radiation protection or on interventional radiology. Authors' professional role and year of publication were recorded for each included guideline. Guideline quality evaluation was performed independently by three authors using the six-domain tool "AGREE II", with an overall guideline quality score divided into three classes: low (<60%), acceptable (60-80%), and good quality (>80%). RESULTS: Our literature search identified 106 citations: after applying exclusion criteria, 11 guidelines published between 2009 and 2018 were included, most of their authors being interventional radiologists (168/224, 75%). Overall quality of included guidelines was acceptable (median 72%, interquartile range 64-83%), with only one guideline (9%) with overall low quality and four guidelines (36%) with overall good quality. Among AGREE II domains, "Scope and Purpose", "Clarity of Presentations", and "Editorial Independence" had the best results (87%, 76%, and 75% respectively), while "Applicability", "Rigor of Development", and "Stakeholder Involvement" the worst (46%, 49%, and 52% respectively). CONCLUSION: Considering all guidelines, the overall methodological quality was acceptable with one third of them reaching the highest score class. The "Applicability" domain had the lowest median score, highlighting a practical implementation gap to be addressed by future guidelines.

Machine Learning to Predict In-Hospital Mortality in COVID-19 Patients Using Computed Tomography-Derived Pulmonary and Vascular Features.

Pulmonary parenchymal and vascular damage are frequently reported in COVID-19 patients and can be assessed with unenhanced chest computed tomography (CT), widely used as a triaging exam. Integrating clinical data, chest CT features, and CT-derived vascular metrics, we aimed to build a predictive model of in-hospital mortality using univariate analysis (Mann-Whitney U test) and machine learning models (support vectors machines (SVM) and multilayer perceptrons (MLP)). Patients with RT-PCR-confirmed SARS-CoV-2 infection and unenhanced chest CT performed on emergency department admission were included after retrieving their outcome (discharge or death), with an 85/15% training/test dataset split. Out of 897 patients, the 229 (26%) patients who died during hospitalization had higher median pulmonary artery diameter (29.0 mm) than patients who survived (27.0 mm, p < 0.001) and higher median ascending aortic diameter (36.6 mm versus 34.0 mm, p < 0.001). SVM and MLP best models considered the same ten input features, yielding a 0.747 (precision 0.522, recall 0.800) and 0.844 (precision 0.680, recall 0.567) area under the curve, respectively. In this model integrating clinical and radiological data, pulmonary artery diameter was the third most important predictor after age and parenchymal involvement extent, contributing to reliable in-hospital mortality prediction, highlighting the value of vascular metrics in improving patient stratification.

Optimizing Loco Regional Management of Oligometastatic Colorectal Cancer: Technical Aspects and Biomarkers, Two Sides of the Same Coin.

Colorectal cancer (CRC) is the third most common cancer worldwide and has a high rate of metastatic disease which is the main cause of CRC-related death. Oligometastatic disease is a clinical condition recently included in ESMO guidelines that can benefit from a more aggressive locoregional approach. This review focuses the attention on colorectal liver metastases (CRLM) and highlights recommendations and therapeutic locoregional strategies drawn from the current literature and consensus conferences. The different percutaneous therapies (radiofrequency ablation, microwave ablation, irreversible electroporation) as well as trans-arterial approaches (chemoembolization and radioembolization) are discussed. Ablation margins, the choice of the imaging guidance as well as characteristics of the different ablation techniques and other technical aspects are analyzed. A specific attention is then paid to the increasing role of biomarkers (in particular molecular profiling) and their role in the selection of the proper treatment for the right patient. In conclusion, in this review an up-to-date state of the art of the application of locoregional treatments on CRLM is provided, highlighting both technical aspects and the role of biomarkers, two sides of the same coin.

Real-Time US-CT fusion imaging for guidance of thermal ablation in of renal tumors invisible or poorly visible with US: results in 97 cases.

PURPOSE: To assess the capability of ultrasound-computed tomography (US-CT) fusion imaging to guide a precise targeting of renal tumors invisible or poorly visible with US. MATERIALS AND METHODS: From 2016 renal tumors poorly visible or inconspicuous/invisible at US were treated at our institution with the guidance of US/CT fusion in a room equipped with CT scanner. Feasibility of the procedure, accuracy of targeting, complications, and technique efficacy were evaluated. RESULTS: Of 227 patients treated from 2016 to March 2020, 91 patients (65 males and 26 females, mean age 68.5 ± 10.1 years) with 97 renal lesions (mean maximum diameter 21.6 ± 9.4 mm) inconspicuous/invisible (29/97, 29.9%) or poorly visible (68/97, 70.1%) at US underwent treatment under US-CT fusion guidance. US-CT fusion imaging guidance was always technically feasible and enabled correct targeting in 97/97/(100%) of cases. Technical success was achieved in 93/97 lesions (95.9%). Three lesions were retreated during the same ablative session, while 1 was retreated in a subsequent session. Thus, primary efficacy was achieved in one session in 96/97 (98.9%) cases and secondary efficacy in 97/97 (100%) cases. CONCLUSION: US-CT image fusion guidance allows for a correct tumor targeting of renal tumors poorly visible or inconspicuous/invisible with US alone, with a high rate of technical success and technique efficacy.

Real-time US/cone-beam CT fusion imaging for percutaneous ablation of small renal tumours: a technical note.

INTRODUCTION: Fusion imaging is gaining attention as an imaging technique to assist minimally invasive tumour ablation. Ultrasound (US) and computed tomography (CT) are the most common imaging modalities to guide thermal ablation of renal tumours, yet cone-beam CT (CBCT) has recently been described to successfully assist percutaneous renal interventions. Our goal was to evaluate primary technical success and correct lesion targeting of US/CBCT fusion imaging to guide the ablation of kidney masses < 2 cm in a small group of patients. MATERIAL AND METHODS: Six renal lesions (maximum diameter 11-17 mm) were treated with RFA in 5 different patients using real-time US/CBCT. Fusion imaging was used to identify and monitor tumour ablation. Demographics, tumour characteristics and mean serum creatinine levels were recorded before and after the procedure. Primary technical success and correct lesion targeting represented the main endpoints of the study. Primary technique efficacy was confirmed at 1-month and 3-month contrast-enhanced CT follow-ups. RESULTS: In all cases, a confident US/CBCT synchronisation was reached and allowed for a correct targeting and a successful percutaneous ablation. Primary technique efficacy was 100%. No recurrence was observed at the follow-up that ranged from 8 to 26 months (mean 16 months). CONCLUSIONS: US/CBCT fusion proved to be a viable method to precisely guide safe and effective percutaneous thermal ablation in patients with small renal tumours, especially when hardly detectable on US. KEY POINTS: • US/CBCT fusion imaging for renal ablation is safe and feasible. • US/CBCT fusion imaging allows for an improved targeting and complete ablation of small RCC with poor US-conspicuity.

Role of Fusion Imaging in Image-Guided Thermal Ablations.

Thermal ablation (TA) procedures are effective treatments for several kinds of cancers. In the recent years, several medical imaging advancements have improved the use of image-guided TA. Imaging technique plays a pivotal role in improving the ablation success, maximizing pre-procedure planning efficacy, intraprocedural targeting, post-procedure monitoring and assessing the achieved result. Fusion imaging (FI) techniques allow for information integration of different imaging modalities, improving all the ablation procedure steps. FI concedes exploitation of all imaging modalities' strengths concurrently, eliminating or minimizing every single modality's weaknesses. Our work aims to give an overview of FI, explain and analyze FI technical aspects and its clinical applications in ablation therapy and interventional oncology.

CT-derived Chest Muscle Metrics for Outcome Prediction in Patients with COVID-19.

Background Lower muscle mass is a known predictor of unfavorable outcomes, but its prognostic impact on patients with COVID-19 is unknown. Purpose To investigate the contribution of CT-derived muscle status in predicting clinical outcomes in patients with COVID-19. Materials and Methods Clinical or laboratory data and outcomes (intensive care unit [ICU] admission and death) were retrospectively retrieved for patients with reverse transcriptase polymerase chain reaction-confirmed SARS-CoV-2 infection, who underwent chest CT on admission in four hospitals in Northern Italy from February 21 to April 30, 2020. The extent and type of pulmonary involvement, mediastinal lymphadenopathy, and pleural effusion were assessed. Cross-sectional areas and attenuation by paravertebral muscles were measured on axial CT images at the T5 and T12 vertebral level. Multivariable linear and binary logistic regression, including calculation of odds ratios (ORs) with 95% CIs, were used to build four models to predict ICU admission and death, which were tested and compared by using receiver operating characteristic curve analysis. Results A total of 552 patients (364 men and 188 women; median age, 65 years [interquartile range, 54-75 years]) were included. In a CT-based model, lower-than-median T5 paravertebral muscle areas showed the highest ORs for ICU admission (OR, 4.8; 95% CI: 2.7, 8.5; P < .001) and death (OR, 2.3; 95% CI: 1.0, 2.9; P = .03). When clinical variables were included in the model, lower-than-median T5 paravertebral muscle areas still showed the highest ORs for both ICU admission (OR, 4.3; 95%: CI: 2.5, 7.7; P < .001) and death (OR, 2.3; 95% CI: 1.3, 3.7; P = .001). At receiver operating characteristic analysis, the CT-based model and the model including clinical variables showed the same area under the receiver operating characteristic curve (AUC) for ICU admission prediction (AUC, 0.83; P = .38) and were not different in terms of predicting death (AUC, 0.86 vs AUC, 0.87, respectively; P = .28). Conclusion In hospitalized patients with COVID-19, lower muscle mass on CT images was independently associated with intensive care unit admission and in-hospital mortality. © RSNA, 2021 Online supplemental material is available for this article.

Investigation of intraoperative factors associated with postoperative pancreatic fistula following laparoscopic left pancreatectomy with stapled closure: a video review-based analysis : Video-review for predictors of pancreatic leak.

INTRODUCTION: Postoperative pancreatic fistula (POPF) following distal pancreatectomy (DP) remains the most frequent complication, potential precursor of more serious events, and mechanisms behind POPF development are not clear. Primary aim of the current study is to investigate correlations between patients' characteristics, including technical intraoperative data assessed by retrospective video review of laparoscopic DP (L-PD), and development of clinically relevant (CR-)POPF and major complication. METHODS: Patients undergoing L-DP whose surgery video was available for review were included in this study. Retrospective video review, performed by two surgeons blinded for postoperative outcomes, was focused on pancreatic neck transection and identification of pancreatic capsule disruption (PCD)/staple line bleeding (SLB). Correlation between clinical, demographic, and intraoperative factors and CR-POPF/major complications and assessment of factors associated with PCD and SLB were investigated. RESULTS: Of 41 L-DP performed at our institution (June 2015-June 2020) using a triple-row stapler (EndoGIA™ Reloads with Tri-Staple™), surgery video was available for 38 patients [men/women, 13/25; median age (range) 62 (25-84) years; median BMI (range) 24 (17-42)]. PCD and SLB occurred in 15(39%) and 19(50%) patients and were concomitant in 9(24%). CR-POPF and major complications occurred in 8(21%) and 12(31%) patients, respectively. PCD, SLB, and PCD + SLB rates were significantly higher among patients with CR-POPF, compared to patients without (all p < 0.05). Among patients with PCD, pancreatic thickness at pancreatic transection site was higher (19 mm), compared to non-PCD patients (13 mm, p < 0.001). A directly proportional relation between PCD, CR-POPF, and major complication rate and pancreatic thickness was confirmed by ROC analysis (AUC = 0.949, 0.798, and 0.740, respectively). CONCLUSION: PCD and SLB close to the staple line detected by retrospective video-review are intraoperatively detectable indicators of severe pancreatic traumatism and a potential precursors of CR-POPF following L-PD. Given the strict correlation between PCD and pancreatic thickness, alternative techniques to stapled closure for pancreatic transection may be recommended for patients with a thick pancreas and modification in postoperative care may be considered in patients with PCD/SLB.

Pulmonary thromboembolism in hospitalised COVID-19 patients at moderate to high risk by Wells score: a report from Lombardy, Italy.

OBJECTIVES: To present a single-centre experience on CT pulmonary angiography (CTPA) for the assessment of hospitalised COVID-19 patients with moderate-to-high risk of pulmonary thromboembolism (PTE). METHODS: We analysed consecutive COVID-19 patients (RT-PCR confirmed) undergoing CTPA in March 2020 for PTE clinical suspicion. Clinical data were retrieved. Two experienced radiologists reviewed CTPAs to assess pulmonary parenchyma and vascular findings. RESULTS: Among 34 patients who underwent CTPA, 26 had PTE (76%, 20 males, median age 61 years, interquartile range 54-70), 20/26 (77%) with comorbidities (mainly hypertension, 44%), and 8 (31%) subsequently dying. Eight PTE patients were under thromboprophylaxis with low-molecular-weight heparin, four PTE patients had lower-limbs deep vein thrombosis at ultrasound examination (performed in 33/34 patients). Bilateral PTE characterised 19/26 cases, with main branches involved in 10/26 cases. Twelve patients had a parenchymal involvement >75%, the predominant pneumonia pattern being consolidation in 10/26 patients, ground glass opacities in 9/26, crazy paving in 5/26, and both ground glass opacities and consolidation in 2/26. CONCLUSION: COVID-19 patients are prone to PTE. ADVANCES IN KNOWLEDGE: PTE, potentially attributable to an underlying thrombophilic status, may be more frequent than expected in COVID-19 patients. Extension of prophylaxis and adaptation of diagnostic criteria should be considered.

CT-derived pulmonary vascular metrics and clinical outcome in COVID-19 patients.

To assess pulmonary vascular metrics on chest CT of COVID-19 patients, and their correlation with pneumonia extent (PnE) and outcome, we analyzed COVID-19 patients with an available previous chest CT, excluding those performed for cardiovascular disease. From February 21 to March 21, 2020, of 672 suspected COVID-19 patients from two centers who underwent CT, 45 RT-PCR-positives (28 males, median age 75, IQR 66-81 years) with previous CTs performed a median 36 months before (IQR 12-72 months) were included. We assessed PnE, pulmonary artery (PA) diameter, ascending aorta (Ao) diameter, and PA/Ao ratio. Most common presentations were fever and dyspnea (15/45) and fever alone (13/45). Outcome was available for 41/45 patients, 15/41 dead and 26/41 discharged. Ground-glass opacities (GGOs) alone were found in 29/45 patients, GGOs with consolidations in 15/45, consolidations alone in 1/45. All but one patient had bilateral pneumonia, 9/45 minimal, 22/45 mild, 9/45 moderate, and 5/45 severe PnE. PA diameter (median 31 mm, IQR 28-33 mm) was larger than before (26 mm, IQR 25-29 mm) (P<0.001), PA/Ao ratio (median 0.83, IQR 0.76-0.92) was higher than before (0.76, IQR 0.72-0.82) (P<0.001). Patients with adverse outcome (death) had higher PA diameter (P=0.001), compared to discharged ones. Only weak correlations were found between ΔPA or ΔPA/Ao and PnE (ρ≤0.453, P≤0.032), with 4/45 cases with moderate-severe PnE and minimal increase in PA metrics. In conclusion, enlarged PA diameter was associated to death in COVID-19 patients, a finding deserving further investigation as a potential driver of therapy decision-making.

Image-guided thermal ablation of central renal tumors with retrograde cold pyeloperfusion technique: a monocentric experience.

Purpose: To evaluate feasibility, safety and efficacy of image-guided thermal ablations associated with retrograde pyeloperfusion in patients with centrally located renal tumors.Materials and methods: 48 patients (15 women, 33 men, mean age 69.1 ± 11.8) were treated with image-guided thermal ablation associated with pyeloperfusion for 58 centrally located renal tumors (mean diameter 32.3 ± 7.32 mm). 7 patients had a single kidney. Microwave and radiofrequency ablation were used. All treatments were performed with ultrasound, CT, or fusion imaging guidance under general anesthesia and simultaneous retrograde cold pyeloperfusion technique.Results: Procedure was feasible in all cases. Technical success and primary technical efficacy were reached in 51/58 (88%) and 45/54 tumors (83%). With a second ablation performed in 5 tumors, secondary technical efficacy was achieved in 50/50 (100%) tumors. Minor and major complications occurred in 8/58 (13%) and 5/58 (8%) tumors. No significative change in renal function occurred after treatment.During follow-up, 5 recurrences occurred, that were retreated with a second ablation. At last follow up (mean 32.2 ± 22.0 months), 41/48 (85%) treated patients were free from disease. The median TTP and PFS were 27.0 (range, 2.3-80.0) and 26.5 months (range, 2.3-80.0), respectively.Conclusion: Image-guided thermal ablation associated with protective pyeloperfusion is a feasible, safe, and effective treatment option for patients with central renal tumors with a minimal impact on renal function and relevant potential to avoid nephrectomy.

Comparison between percutaneous and laparoscopic microwave ablation of hepatocellular carcinoma.

Background: Based on patient and tumor characteristics, some authors favor laparoscopic microwave ablation (LMWA) over the percutaneous approach (PMWA) for treatment of hepatocellular carcinoma (HCC). We compared the two techniques in terms of technique efficacy, local tumor progression (LTP) and complication rates.Study design: A retrospective comparative analysis was performed on 91 consecutive patients (102 HCC tumors) who underwent PMWA or LMWA between October 2014 and May 2019. Technique efficacy at one-month and LTP at follow-up were assessed by contrast-enhanced CT/MRI. Kaplan-Meier estimates and Cox regression were used to compare LTP-free survival (LTPFS).Results: At baseline analysis, LMWA group showed higher frequency of multinodular disease (p < .001) and average higher energy delivered over tumor size (p = .033); PMWA group showed higher rates of non-treatment-naïve patients (p = .001), patients with Hepatitis-C (p = .03) and BCLC-A1 disease (p = .006). Technique efficacy was not significantly different between the two groups (p = .18). Among effectively treated patients, 75 (83 tumors) satisfied ≥6 months follow-up, 54 (57 tumors) undergoing PMWA and 21 (26 tumors) LMWA. LTP occurred in 14/83 cases (16.9%): 12 after PMWA (21.1%) and 2 after LMWA (7.7%). At univariate analysis, technique did not correlate to LTPFS (p = .28). Subgroup analysis showed a trend toward worse LTPFS after PMWA of subcapsular tumors (p = .16). Major complications were observed in six patients (6.6%), 2 after PMWA and 4 after LMWA (3.2% vs 14.3%, p = .049).Conclusions: Technical approach did not affect LTPFS. Complications were reported more frequently after LMWA. Despite higher complication rates, LMWA seems a valid option for treatment of subcapsular tumors.

Reproducibility of Ablated Volume Measurement Is Higher with Contrast-Enhanced Ultrasound than with B-Mode Ultrasound after Benign Thyroid Nodule Radiofrequency Ablation-A Preliminary Study.

The reproducibility of contrast-enhanced ultrasound (CEUS) and standard B-mode ultrasound in the assessment of radiofrequency-ablated volume of benign thyroid nodules was compared. A preliminary study was conducted on consecutive patients who underwent radiofrequency ablation (RFA) of benign thyroid nodules between 2014 and 2016, with available CEUS and B-mode post-ablation checks. CEUS and B-mode images were retrospectively evaluated by two radiologists to assess inter- and intra-observer agreement in the assessment of ablated volume (Bland-Altman test). For CEUS, the mean inter-observer difference (95% limits of agreement) was 0.219 mL (-0.372-0.809 mL); for B-mode, the mean difference was 0.880 mL (-1.655-3.414 mL). Reproducibility was significantly higher for CEUS (85%) than for B-mode (27%). Mean intra-observer differences (95% limits of agreement) were 0.013 mL (0.803-4.097 mL) for Reader 1 and 0.031 mL (0.763-3.931 mL) for Reader 2 using CEUS, while they were 0.567 mL (-2.180-4.317 mL, Reader 1) and 0.759 mL (-2.584-4.290 mL, Reader 2) for B-mode. Intra-observer reproducibility was significantly higher for CEUS (96% and 95%, for the two readers) than for B-mode (21% and 23%). In conclusion, CEUS had higher reproducibility and inter- and intra-observer agreement compared to conventional B-mode in the assessment of radiofrequency-ablated volume of benign thyroid nodules.