Toskich, Beau

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.

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.

AbstractEfforts to improve mortality associated with locally advanced pancreatic cancer (LAPC) have shown minimal gains despite advances in surgical technique, systemic treatments, and radiation therapy. Locoregional therapy with ablation has not been routinely adopted due to the high risk of complications associated with thermal destruction of the pancreas. Irreversible electroporation (IRE) is an emerging, nonthermal, ablative technology that has demonstrated the ability to generate controlled ablation of LAPC while preserving pancreatic parenchymal integrity. IRE may be performed percutaneously or via laparotomy and will commonly involve multidisciplinary treatment teams. This article will describe the technical aspects of how multidisciplinary IRE is performed during laparotomy at a single tertiary care institution.

AbstractAblation is now recommended by international guidelines for the definitive treatment of hepatocellular carcinoma (HCC). Extensive clinical studies have demonstrated outcomes comparable to surgical resection with shorter hospital stays, decreased costs, and improved quality of life. Successful ablation requires complete treatment of both tumor and margin while preserving critical adjacent structures. HCC exhibits highly variable presentations in both anatomic involvement and biology which have significant implications on choice of ablative therapy. There are now abundant ablation modalities and adjunctive techniques which can be used to individualize ablation and maximize curative results. This article provides a patient-centered summary of approaches to HCC ablation in the context of patient performance, hepatic reserve, tumor phenotype and biology, intra- and extrahepatic anatomy, and ablation technology.

AbstractThermal ablation is widely regarded as definitive therapy for early-stage hepatocellular carcinoma, but its efficacy decreases in tumors greater than 3 cm. Extensive clinical studies have supported improved outcomes provided through combining transarterial embolic therapy with ablation in the treatment of larger tumors. This article will provide a survey of the science and data for combination therapy in both thermal and nonthermal ablation modalities, as well as describe emerging applications.

Organizing pneumonia is a recognized complication after external beam radiotherapy of breast and lung cancer but has not been described after radioembolization. A 67-year-old female who underwent ablative trans-arterial radioembolization for the treatment of hepatic metastatic renal cell carcinoma adjacent to the diaphragm presented with computed tomography findings of asymptomatic organizing pneumonia in the lower lobes. A follow-up computed tomography 8 months after conservative management demonstrated near-total resolution of the previous pulmonary parenchymal disease. The patient continues to remain asymptomatic and shows no evidence of residual tumor 10 months after radioembolization.

AbstractObjectiveTo determine laparoscopic accessibility of liver lobes and access to the hilus and describe laparoscopic microwave ablation (LMWA) in 2 dogs with hepatic neoplasia.Study designExperimental/descriptive case series.Sample populationSix canine cadavers and 2 clinical dogs.MethodsCadavers in dorsal recumbency underwent laparoscopic assessment of the liver. A 17 gauge MWA probe was inserted to create an ablation zone at the most proximal aspect of the hilus. The distance from the center of each ablation zone to the most proximal aspect of the corresponding hilus was determined. Two dogs with hepatic neoplasia underwent LMWA.ResultsAll lobes of the canine liver were accessible via laparoscopy. The median (interquartile range) distances from the ablation zones to the hilus for the caudate process, left lateral, left middle, quadrate, right lateral, and right middle lobes were 2.2 (1.2–2.6), 2.1 (1–4.4), 1.5 (1.4–3.7), 2, 1, 2.5 (1–4.1) cm, respectively. Histopathologic diagnoses treated by LMWA included metastatic hemangiosarcoma and primary hepatocellular carcinoma. Laparoscopic microwave ablation was technically feasible, and no complications from the procedure resulted.ConclusionLaparoscopic access to the hilus of each liver lobe is possible via a ventrodorsal approach provided reverse Trendelenburg and lateral rotation is used, especially for the right lateral lobe. Laparoscopic microwave ablation is feasible in some dogs with hepatic neoplasia. The indications for and efficacy of LMWA for hepatic neoplasia in dogs requires additional investigation.Clinical significanceLaparoscopic access to all liver lobes and MWA of some neoplastic lesions is feasible in a canine pilot study.

Abstract Quantifying lymph nodes in vascularized lymph node transfer (VLNT) has been performed using preoperative percutaneous ultrasound. The higher resolution and accuracy of intraoperative ultrasound (IOUS) over transcutaneous ultrasound has been demonstrated in the radiology literature for the identification and characterization of finer structures including hepatic lesions, pancreatic lesions, and biliary or pancreatic ducts. We hypothesize that IOUS during VLNT would be a superior method to quantify and map lymph nodes in our flaps. A prospectively collected database of patients undergoing VLNT over 3 years (October 2014 to October 2017) was reviewed. Patients who underwent IOUS during flap harvest, before pedicle ligation to simultaneously map and quantify the number of lymph nodes were included in the study. Twenty-one patients with an average age of 58.7 years and a mean BMI of 32.3 underwent VLNT with IOUS for chronic lymphedema during the study period. Extremity lymphedema was classified as Campisi IB (n = 7), IIA (n = 7), IIB (n = 5), and IIIA (n = 2). There were 14 superficial circumflex iliac artery flaps, including 4 performed concomitantly with a deep inferior epigastric perforator flap, 1 transverse cervical artery flap, and 6 omental flaps. The average number of lymph nodes transferred per IOUS was 4.3 for superficial circumflex iliac artery flaps, 4 for the transverse cervical artery flap, and 5.2 for the omental flaps. Intraoperative ultrasound allows the lymphatic surgeon to precisely map the location of lymph nodes which can guide intraoperative decision making. As there is no data correlating the number of lymph nodes transferred and outcomes after VLNT, developing a precise intraoperative quantification method is important.