Citations

AbstractRadioembolization dosimetry for the treatment of hepatocellular carcinoma has evolved alongside our understanding of best practice for this therapy. At the core of advances in dosimetry are personalized and ablative applications of radioembolization, which have generated paradigm shifts in both safety and efficacy. This review provides a summary of fundamental radioembolization dosimetry concepts and narrates how our approach to treating patients has shifted from conventional to tailored and definitive therapy.

TPS358 Background: The anti–PD-L1 antibody ATEZO prevents PD-L1 from interacting with PD-1 and B7.1, thus reinvigorating antitumor T cell activity. Anti-VEGF BEV can increase dendritic cell maturation, enhance T cell infiltration, and reduce myeloid-derived suppressor cells and regulatory T-cells in tumors. This combination has been FDA approved for first-line treatment of advanced HCC based on the IMbrave 150 study. On the other hand, locoregional radiotherapy (e.g., Y90 TARE) enhances the diversity of the intratumoral T cell receptor repertoire. It is the standard of care for pts with intermediate-stage HCC (iHCC). Based on preclinical and clinical data, we hypothesize that the combination of Y90 TARE, BEV, and ATEZO induces synergistic tumor-killing. Methods: This is an open-label, multicenter, randomized phase II study of Y90 TARE and BEV plus ATEZO compared with Y90 TARE alone in pts with unresectable IHCC. The primary study objective is to assess and compare the progression-free survival (PFS) (per mRECIST 1.1) of pts in each arm. The main secondary objective is to determine the safety and tolerability (CTCAE v5) of TARE combined with ATEZO and BEV in pts with HCC. Exploratory objectives are to assess the role of the immunoscore and PD-L1 expression levels in the prediction of improved clinical outcome in pts receiving Y-90 TARE and BEV plus ATEZO; the composition of tumor-infiltrating immune cell subtypes in predicting response to a chosen therapy; how Y90 therapy affects the proportion of antigen-presenting cells in the tumor; and symptoms experienced by pts receiving TARE and BEV plus ATEZO treatment, using patient-reported outcomes. Eligible pts have either HCC that is not amenable to surgical resection, confirmed by pathology review, or at least BCLC stage B HCC outside of downstaging criteria. Other standard eligibility criteria apply. Pts must have a pretreatment liver biopsy taken and then be randomized 1:1 to TARE (Arm A) or TARE followed by ATEZO and BEV (Arm B). Pts will have TARE mapping during week (wk) 1 and TARE treatment during wk 2. In Arm B, pts will start BEV plus ATEZO 4 wks (±1 wk) after TARE treatment. Pts will have abdominal MRI or CT scans every 12 weeks, CT scans of the chest every 24 wks, and a second tumor biopsy at 4 wks. Disease progression will be captured by both RECIST 1.1 and mRECIST. We plan to assess the safety of TARE with BEV and ATEZO in the first 10 pts randomized to Arm B for two cycles. If there are no grade ≥ 3 unexpected toxicities possibly, probably or definitely related to combined TARE plus BEV plus ATEZO, the study will continue to accrue 128 pts in total. Pts will continue study treatment (Arm B) for a total of 24 months from initiation of TARE or until intolerable toxicity or disease progression occur, whichever is earlier. Enrollment began in September 2020. Clinical trial information: NCT04541173.

Background To review long-term outcomes and saphenous vein (SV) occlusion rate after endovenous ablation (EVA) for symptomatic varicose veins. Methods A review of our EVA database (1998–2018) with at least 3-years of clinical and sonographic follow-up. The primary end point was SV closure rate. Results 542 limbs were evaluated. 358 limbs had radiofrequency and 323 limbs had laser ablations; 542 great saphenous veins (GSV), 106 small saphenous veins (SSV) and 33 anterior accessory saphenous veins (AASV) were treated. Follow-up was 5.6 ± 2.3 years; 508 (74.6%) veins were occluded, 53 (7.8%) partially occluded and 120 (17.6%) were patent. On multivariable Cox regression analysis, male sex (HR 1.6, 95% CI [0.46–018], p = 0.012) and use anticoagulation (HR 2.0, 95% CI [0.69–0.34], p = 0.044) were predictors of long-term failure. On Kaplan-Meier curve, we had an 86.3% occlusion rate. Conclusion Our experience revealed a 5-year closure rate of 86.3%. Ablations have satisfactory occlusion rate.

Abstract OBJECTIVE To determine the optimal energy profile for and to assess the feasibility and efficacy of ultrasonographic and laparoscopic guidance for microwave ablation (MWA) of clinically normal canine ovaries. SAMPLE 44 extirpated ovaries from 22 healthy dogs. PROCEDURES In the first of 2 trials, 13 dogs underwent oophorectomy by routine laparotomy. Extirpated ovaries underwent MWA at 45 W for 60 (n = 11) or 90 (12) seconds; 3 ovaries did not undergo MWA and served as histologic controls. Ovaries were histologically evaluated for cell viability. Ovaries without viable cells were categorized as completely ablated. Histologic results were used to identify the optimal MWA protocol for use in the subsequent trial. In the second trial, the ovaries of 9 dogs underwent MWA at 45 W for 90 seconds in situ. Ultrasonographic guidance for MWA was deemed unfeasible after evaluation of 1 ovary. The remaining 17 ovaries underwent MWA with laparoscopic guidance, after which routine laparoscopic oophorectomy was performed. Completeness of ablation was histologically assessed for all ovaries. RESULTS 2 ovaries were excluded from the trial 1 analysis because of equivocal cell viability. Six of 11 ovaries and 10 of 10 ovaries that underwent MWA for 60 and 90 seconds, respectively, were completely ablated. In trial 2, laparoscopic-guided MWA resulted in complete ablation for 12 of 17 ovaries. Dissection of the ovarian bursa for MWA probe placement facilitated complete ablation. CONCLUSIONS AND CLINICAL RELEVANCE Laparoscopic-guided MWA at 45 W for 90 seconds was feasible, safe, and effective for complete ablation of clinically normal ovaries in dogs.

AbstractAcute mesenteric ischemia (AMI) remains a vascular emergency. Our aim was to explore readmission for AMI. We identified all patients admitted for AMI from the state of California through the Healthcare and Utilization Project from 2005 to 2011. Our primary end point was the rate and etiology for readmission. Our secondary end points were the length of hospitalization and in-hospital mortality. Cox proportional hazard regression was utilized to assess risk of 30-day readmission. There were 534 (9.9%) readmissions at 30 days. The mean age was 67 ± 17 years and 209 (39.1%) were male. The five most common etiologies for readmission were AMI (7.6%), cardiac events (5.3%), severe sepsis (1.2%), dehydration (1.1%), and acute kidney failure (1.1%). Once readmitted, these patients were most likely to experience cardiac catheterizations (25.4%), red blood cell transfusions (23.6%), intubation and mechanical ventilation (17.6%), biopsy of the large intestine (13.9%), reoperation for small bowel resection (10.9%), administration of total parenteral nutrition (10.5%), and transfusion of other blood products (6.9%). This hospitalization was 8.8 ± 12.7 days long. In-hospital mortality was 36 patients (6.7%). On multivariable Cox-regression analysis, severe (hazard ratio [HR]: 2.1 [1.4–3.2], p = 0.0005) and moderate (HR: 1.5 [1.03–2.13], p = 0.04) Elixhauser Comorbidity Group, complications (HR: 1.5 [1.2–1.9], p = 0.0007), and longer index hospitalization (HR: 1.02 [1.01–1.02], p < 0.0001) were predictors of readmission. Conclusion AMI remains a vascular emergency. Readmissions have a significant rate of morbid invasive procedures and can lead to an in-hospital mortality of 6.7%. The adoption of guidelines similar to the European Society for Trauma and Emergency Surgery should be considered.

Objective: The objective of this study was to compare posttransplant outcomes in patients undergoing bridging locoregional therapy (LRT) with Y-90 transarterial radioembolization (TARE) based protocol compared with transarterial chemoembolization based protocol for hepatocellular carcinoma (HCC) prior liver transplantation (LT). Materials and Methods: Patients listed for LT with HCC within the Milan criteria at our center who had bridging LRT were treated according to transarterial chemoembolization (TACE) based protocol from May 2012 to April 2014 and a TARE based protocol from October 2014 to December 2017. Early posttransplant survival and tumor recurrence were compared between the groups. Tumor response to LRT, microvascular invasion (mVI), and the rate of delisting was also evaluated. Results: One hundred three patients who were listed for LT with HCC within the Milan criteria received LRT. LT was performed in 65 patients, 28 treated with TARE protocol and 37 on TACE protocol. There were no statistical differences in baseline pretransplant characteristics and tumor recurrence. There was a trend toward improved 3-year survival in the TARE group (92.9% vs. 75.7%; P=0.052). The mVI was seen in 1/28 (3.6%) explants in the TARE group compared with 10/37 (27%) in the TACE group (P=0.013). The TARE group also required fewer LRT treatments (1.46 vs. 2.43; P=0.001) despite no difference in time on the transplant list. Conclusions: Despite requiring fewer LRT treatments, there was significantly less mVI in the explants of patients treated with TARE protocol LRT as a bridge to LT as well as a trend toward improved 3-year survival. Therefore, TARE may be associated with improved tumor control and reduced post-LT recurrence.