Elena Bozzi

The management of de novo kidney tumors (DKTs) after liver transplantation (LT) is challenging due to previous transplant surgery and calcineurin inhibitors (CNI)-related nephrotoxicity. Minimally invasive renal-sparing strategies like robot-assisted partial nephrectomy (RPN) are favored, but a transperitoneal approach may be limited by the previous transplant surgery and the location of the DKT; in such cases, CT-guided cryoablation may be an alternative option. In this retrospective cohort study, we aimed to compare RPN and cryoablation for the treatment of DKT in LT recipients. The primary endpoints were the efficacy (R0 resection in RPN, absence of the tumor at first follow-up for cryoablation) and the safety of the procedures (postoperative morbidity and increase in creatine level). The periprocedural costs and the oncologic efficacy (recurrence and overall survival) were the secondary endpoints. Twelve LT recipients (91.7% males, mean age 65 years) underwent RPN (n = 6) or cryoablation (n = 6) for DKT; the median interval between LT and diagnosis of DKT was 142.5 vs. 117.5 months, respectively. Efficacy was obtained in all patients after RPN and cryoablation. Postoperative morbidity was 16.7% in each group, and the postoperative increase in creatinine values was similar. Hospital stay was shorter following cryoablation vs. RPN (3.1 vs. 6.7 days; p = 0.03). The mean procedural costs were higher for RPN. There was no mortality and none of the patients had signs of recurrence after a median follow-up of 40.5 months. Both RPN and CT-guided cryoablation were safe and effective for the treatment of selected patients with DKT after LT. When applicable, cryoablation may be cost-effective and provide faster recovery.

Introduction: Percutaneous thermal segmentectomy is a single-step combination of microwave ablation, performed during arterial occlusion obtained with a balloon micro catheter, followed in the same session by balloon-occluded TACE. The aim of this multicenter retrospective study is to report the mid-term oncological performance of this technique for liver malignancies > 3.0 cm and to identify risk factors for the loss of sustained complete response. Methods: Oncological results were evaluated with CT or MRI according to m-RECIST (HCC) and RECISTv1.1 (metastasis/intra-hepatic cholangiocarcinoma, iCC) at 1-month, 3–6-month and then at regular-6-month intervals. To identify predictive variables associated with not achieving or losing complete response two mixed-effects multivariable logistic regression models were constructed. Results: Sixty-three patients (40/23, male/female) with primary liver malignancies (HCC = 49; iCC = 4) and metastasis (n = 10) were treated. Median diameter of target lesion was 4.5 cm (range 3.0–7.0 cm). The median follow-up time was 9.2 months. At one-month follow-up, 79.4% of patients presented with a complete response and the remaining 20.6% were partial responders. At the 3–6-month follow-up, reached by 59 of the initial 63 patients, 83.3% showed a sustained complete response, while 10.2% had a partial response and 8.5% a local recurrence. At the last follow-up, 69.8% of the lesions showed a complete response. The initial diameter of the target lesion ≥ 5.0 cm was the only independent variable associated with the risk of failure in maintaining a complete response at 6 months (OR = 8.58, 95% CI 1.38–53.43; P = 0.02). Conclusion: Percutaneous thermal segmentectomy achieves promising oncological results in patients with tumors > 3.0 cm, with tumor dimension ≥ 5.0 cm being the only risk factor associated with the failure of a sustained complete response.

Aim To report the multicenter retrospective experience on combination of balloon-occluded MWA(b-MWA) followed by balloon-occluded TACE(b-TACE) in patients with liver malignancies > 3 cm, focusing on appearance and volume of necrotic area, safety profile and oncological results. Materials and Methods Twenty-three patients with liver primary malignancies (hepatocellular carcinoma,HCC = 18; intrahepatic cholangiocarcinoma,iCC = 2) and metastasis (colorectal cancer metastasis = 1;sarcoma metastasis = 1;breast metastasis = 1) were treated. Maximum mean diameter of lesions was 4.4 cm (± 1 cm). Treatments were performed using a single-step approach:b-MWA was performed after balloon-microcatheter inflation, followed by b-TACE (with epirubicin or irinotecan). Necrotic area shape and discrepancy with the expected volume of necrosis suggested by vendor’s ablation chart were assessed at post-procedural CT. Complications were categorized according to CIRSE classification. Oncological results at 1 and 3–6 months were evaluated using m-RECIST(HCC) and RECISTv1.1(metastasis/iCC). Results Mean volume of necrotic area was 75 cm³ (± 36). Discrepancy with vendor chart consisted in a medium percentage of volumetric incrementation of necrotic area of 103.2% (± 99.8). Non-spherical shape was observed in 22/23 patients (95.7%). No complications occurred; Post-embolization syndrome occurred in 12/23patients. Complete response and partial response were, respectively, 91, 3% (21/23) and 8.7% (2/23) at 1 month, 85.7% (18/21) and 9.5% (2/21) at 3–6 months. Progression of disease was 4.7% (1/21) at 3–6 months for extra-hepatic progression. Among partial responders, average percentage of tumor volume debulking was 78.8% (± 9.8%). Conclusion b-MWA followed by b-TACE in a single-step procedure led to larger necrotic areas than the proposed by vendors ablation chart, non-spherical in shape and corresponded to the vascular segment occluded during ablation. This permitted to safely achieve promising oncological results in patients with > 3 cm tumors.

Background: In the context of the coronavirus disease 2019 (COVID-19) pandemic, liver-directed therapies (LDTs) may offer minimally invasive integrative tools for tumor control. Among them, selective internal radiation therapy (SIRT) represents a safe, flexible and effective treatment. Purpose of this study is to present our experience with SIRT during the first wave of COVID-19 pandemic and provide an overview of the indications and challenges of SIRT in this scenario. Methods: We retrospectively analyzed the number of patients evaluated by Multidisciplinary Liver Tumor Board (MLTB) and who were undergoing LDTs between March and July 2020 and compared it with 2019. For patients treated with SIRT, clinical data, treatment details and the best radiological response were collected. Results: Compared to 2019, we observed a 27.5% reduction in the number of patients referred to MLTB and a 28.3% decrease in percutaneous ablations; transarterial chemoembolizations were stable, while SIRT increased by 64%. The majority of SIRT patients (75%) had primary tumors, mostly HCC. The best objective response and disease control rates were 56.7% and 72.2%, respectively. Conclusion: The first wave of the COVID-19 pandemic was characterized by an increased demand for SIRT, which represents a safe, flexible and effective treatment, whose manageability will further improve by simplifying the treatment workflow, developing user-friendly and reliable tools for personalized dosimetry and improving interdisciplinary communication.

Microwave (MW) ablation is a worldwide-diffused technique for the percutaneous ablation of hepatocellular carcinoma (HCC). Nevertheless, the efficacy of this technique still needs to be confirmed in pathological specimens. The purpose of this study was to evaluate the efficacy of MW ablation by correlation with histology in excised liver samples at the time of liver transplantation (LT). All patients with MW-ablated HCC who subsequently underwent LT between 2012 and 2020 were retrospectively evaluated. In the explanted livers, the treated lesions were evaluated at pathology, and the necrosis was classified as complete or partial. Thirty-six HCCs were ablated in 30 patients (20.9 ± 6.1 mm, a range of 10–30 mm). Ablations were performed with a single insertion of a MW antenna under ultrasound or CT guidance. A complete radiological response was demonstrated in 30/36 nodules (83.3%) in 24/30 patients (80%) at imaging performed one-month after MW ablation. At pathology, of the 36 treated nodules, 28 (77.8%) showed a complete necrosis, and 8 (22.2%) showed a pathological partial necrosis. Good agreement was found between the imaging performed one-month after treatment and the complete pathological response (Cohen’s k = 0.65). The imaging accuracy in detecting a complete response to treatment was 88.9%. All lesions with complete necrosis did not show recurrence at follow-up imaging until transplantation. The rad-path correlation in the explanted livers showed that MW ablation achieved a high rate of complete necrosis if a macroscopical complete ablation was obtained.

To study the correlation between the overall coagulation zone (A) attained in percutaneous microwave ablation (MWA) of hepatocellular carcinomas (HCC) and: (1) the hyperdense zone (C) visible in the central part of zone A on post-treatment unenhanced CT scans; (2) the deposited energy; (3) the coagulation zones observed on ex-vivo bovine liver. The post-procedural computed tomography (CT) scans of HCCs treated with a single energy deployment through the same 2450 MHz MWA system were retrospectively analyzed, retrieving the dimensions of A and C zones and the deposited energy (E). Ex-vivo bovine liver MWA with the same system were performed and analyzed to determine the same quantities by gross-pathologic examination and CT imaging. A total of 101 HCC treatments were analyzed. The average coagulation volumes increased linearly with deposited energy (1.11 cc/kJ, R² = 0.90, 4.2 kJ ≤ E ≤ 48 kJ), similarly to ex-vivo findings (1.38 cc/kJ, R² =0.97, 7.2 kJ ≤ E ≤ 144 kJ). The long axis (L) and short axis (D) of zones A and C held a fairly constant ratio both in-vivo (L_C/L_A=0.43 ± 0.13; D_C/D_A=0.42 ± 0.10) and ex-vivo (L_C/L_A = 0.49 ± 0.07; D_C/D_A = 0.28 ± 0.06). The average dimensions of the ablation zone induced by the considered system on HCC increase linearly with the deposited energy and are fairly well predicted by the corresponding ex-vivo dimensions. The ratio between each linear dimension of A and C zones was found to be roughly constant over a large deposited energy span, both ex-vivo and in-vivo.

Purpose To assess feasibility of proper hepatic artery catheterization using a 3D model obtained from preprocedural computed tomographic angiography (CTA), fused with real-time fluoroscopy, during transarterial chemoembolization of hepatocellular carcinoma. Methods Twenty consecutive cirrhotic patients with hepatocellular carcinoma undergoing transarterial chemoembolization were prospectively enrolled onto the study. The early arterial phase axial images of the preprocedural CTA were postprocessed on an independent workstation connected to the angiographic system (Innova 4100; GE Healthcare, Milwaukee, WI), obtaining a 3D volume rendering image (VR) that included abdominal aorta, splanchnic arteries, and first and second lumbar vertebrae. The VR image was manually registered to the real-time X-ray fluoroscopy, with the lumbar spine used as the reference. The VR image was then used as guidance to selectively catheterize the proper hepatic artery. The procedure was considered successful when performed with no need for intraarterial contrast injections or angiographic acquisitions. Results The procedure was successful in 19 (95 %) of 20 patients. In one patient, celiac trunk angiography was required for the presence of a significant ostial stenosis that was underestimated at computed tomography. Time for image reconstruction and registration was <10 min in all cases. Conclusion The use of preprocedural CTA model with fluoroscopy enables confident and direct catheterization of the proper hepatic artery with no need for preliminary celiac trunk angiography, thus reducing radiation exposure and contrast media administration.

Hepatocellular carcinoma (HCC) is the fifth most common neoplasia in the world. In the past, treatment of advanced HCC with conventional antineoplastic drugs did not result in satisfactory outcomes: recently, in this patient population the oral multikinase inhibitor sorafenib has been able to induce a statistically significant improvement of overall survival. Similarly to other anti-angiogenic drugs employed in other tumour types, also sorafenib seldom induces the dimensional tumour shrinking usually observed with conventional cytotoxic drugs: data gathered from studies carried out with sorafenib and other competitors under development do not report any complete response in HCV-induced HCC.