Computational evaluation of inferior vena cava filters through computational fluid dynamics methods

Numerical simulation is growing in its importance toward the design, testing and evaluation of medical devices. Computational fluid dynamics and finite element analysis allow improved calculation of stress, heat transfer, and flow to better understand the medical device environment. Current research focuses not only on improving medical devices, but also on improving the computational tools themselves. As methods and computer technology allow for faster simulation times, iterations and trials can be performed faster to collect more data. Given the adverse events associated with long-term inferior vena cava (IVC) filter placement, IVC filter design and device evaluation are of paramount importance. This work reviews computational methods used to develop, test, and improve IVC filters to ultimately serve the needs of the patient

Intraoperative Embolization during Inferior Vena Cava Tumor Thrombectomy for Renal Cell Carcinoma

Intraoperative tumor thrombus embolization is a potentially lethal complication during inferior vena cava (IVC) thrombectomy for renal cell carcinoma (RCC). Intraoperative embolization is uncommonly encountered because IVC thrombectomy surgical technique is focused on avoiding this complication. Nonetheless, early recognition of embolization is essential so that emergent management can be instituted. When available, cardiopulmonary bypass (CPB) and embolectomy should be considered the gold standard for the management of intraoperative embolization. Several novel endovascular techniques are also available for selective use. We present the case of a 71-year-old female with a right renal mass and level II (retrohepatic) IVC tumor thrombus. During cytoreductive nephrectomy and IVC thrombectomy, tumor embolization was diagnosed during a period of hypotension based on transesophageal echocardiographic finding of new thrombus within the right atrium. This prompted sternotomy, CPB, and pulmonary artery embolectomy. The patient survived this embolization event and has a complete response to systemic therapy 9 months postoperatively. This case serves as the framework for a discussion on management considerations surrounding intraoperative embolization during IVC thrombectomy

Locoregional Therapies for Hepatobiliary Tumors: Contemporary Strategies and Novel Applications

A large majority of primary hepatobiliary tumors are hepatocellular carcinomas (HCC), with the remainer being cholangiocarcinoma. While surgical resection remains the gold standard treatment for hepatobiliary tumors, relatively few patients are operative candidates, and systemic treatments have limited effectiveness. Locoregional therapies offer significant promise in the management of HCC. Ablation and radioembolization may offer similar outcomes to surgery for early-stage hepatocellular carcinoma while radioembolization and chemoembolization are valuable in the management of advanced disease. There is significantly less evidence for the role of locoregional therapy in the treatment of cholangiocarcinoma, although it appears to be well tolerated

Locoregional Approaches in Cholangiocarcinoma Treatment

Cholangiocarcinoma (CCA) is a rare hepatic malignant tumor with poor prognosis due to late detection and anatomic factors limiting the applicability of surgical resection. Without surgical resection, palliation is the most common approach. In non-surgical cases contained within the liver, locoregional therapies provide the best chance for increased survival and disease control. The most common methods, transarterial chemoembolization and transarterial radioembolization, target tumors by embolizing their blood supply and limiting the tumor’s ability to metabolize. Other treatments induce direct damage via thermal ablation to tumor tissue to mediate their anti-tumor efficacy. Recent studies have begun to explore roles for these therapies outside their previous role of palliation. This review will outline the mechanisms of each of these treatments, along with their effects on overall survival, while comparing these to non-locoregional therapies

Locoregional Therapies for Hepatocellular Carcinoma with Portal Vein Tumor Thrombosis

Hepatocellular carcinoma is the fourth leading cause of cancer worldwide, and the fastest increasing cause of cancer mortality in the United States. Its propensity for vascular invasion leads to the presence of portal vein tumor thrombus in up to half of patients. PVTT results in a classification of advanced disease, given the risk recurrence secondary to intravascular spread, and formal guidelines recommend systemic therapy in these patients. However, recent advances in locoregional therapies including TACE, TARE, and ablation have demonstrated the potential to drastically improve overall survival in patients with HCC complicated by PVTT

Liver-Directed Locoregional Therapies for Neuroendocrine Liver Metastases: Recent Advances and Management

Neuroendocrine tumors (NETs) are a heterogeneous class of cancers, predominately occurring in the gastroenteropancreatic system, which pose a growing health concern with a significant rise in incidence over the past four decades. Emerging from neuroendocrine cells, these tumors often elicit paraneoplastic syndromes such as carcinoid syndrome, which can manifest as a constellation of symptoms significantly impacting patients’ quality of life. The prognosis of NETs is influenced by their tendency for metastasis, especially in cases involving the liver, where the estimated 5-year survival is between 20 and 40%. Although surgical resection remains the preferred curative option, challenges emerge in cases of neuroendocrine tumors with liver metastasis (NELM) with multifocal lobar involvement, and many patients may not meet the criteria for surgery. Thus, minimally invasive and non-surgical treatments, such as locoregional therapies, have surfaced. Overall, these approaches aim to prioritize symptom relief and aid in overall tumor control. This review examines locoregional therapies, encompassing catheter-driven procedures, ablative techniques, and radioembolization therapies. These interventions play a pivotal role in enhancing progression-free survival and managing hormonal symptoms, contributing to the dynamic landscape of evolving NELM treatment. This review meticulously explores each modality, presenting the current state of the literature on their utilization and efficacy in addressing NELM

Locoregional Therapy for Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) has a poor prognosis, and surgical resection (SR) offers the only potential for cure. Unfortunately, only a small proportion of patients are eligible for resection due to locally advanced or metastatic disease. Locoregional therapies (LRT) are often used in unresectable liver-only or liver-dominant ICC. This review explores the role of these therapies in the treatment of ICC, including radiofrequency ablation (RFA), microwave ablation (MWA), transarterial chemoembolization (TACE), transarterial radioembolization (TARE), external beam radiotherapy (EBRT), stereotactic body radiotherapy (SBRT), hepatic arterial infusion (HAI) of chemotherapy, irreversible electroporation (IE), and brachytherapy. A search of the current literature was performed to examine types of LRT currently used in the treatment of ICC. We examined patient selection, technique, and outcomes of each type. Overall, LRTs are well-tolerated in the treatment of ICC and are effective in improving overall survival (OS) in this patient population. Further studies are needed to reduce bias from heterogenous patient populations and small sample sizes, as well as to determine whether certain LRTs are superior to others and to examine optimal treatment selection

Examining the Efficacy and Safety of Combined Locoregional Therapy and Immunotherapy in Treating Hepatocellular Carcinoma

More than 800,000 people worldwide are diagnosed with HCC (hepatocellular carcinoma) each year, with approximately 700,000 deaths alone occurring in that same year. Treatment of HCC presents complex therapeutic challenges, particularly in intermediate and advanced stages. LRTs such as transarterial chemoembolization (TACE) and ablations have been the mainstay treatment for early to intermediate-stage HCC, and systemic therapies are used to treat intermediate-late-stage HCC. However, novel literature describing combining LRT with systemic therapies has shown promising results. This review explores recent advances in both liver-directed techniques for hepatocellular carcinoma, including bland transarterial embolization, chemoembolization, radioembolization, and ablative therapies in conjunction as well as with systemic therapies, with a focus on combination therapies, patient selection, procedural technique, periprocedural management, and outcomes. Our findings suggest that LRT combined with systemic therapies is a viable strategy for improving progression-free survival and time to progression for patients with intermediate-to-late-stage HCC. However, further investigation is required to refine treatment protocols and define patient cohorts that would benefit the most

Erosion of embolization coil into the renal collecting system: Retrograde fragmentation of stone and coil via thulium laser lithotripsy

A 50-year-old female developed kidney stones on an eroded embolization coil 16 months after percutaneous nephrolithotomy (PCNL) related bleeding complications. Retrograde ureteroscopy and thulium laser lithotripsy was performed to fragment the exposed portion of the coil into clinically insignificant pieces. Thulium laser coil fragmentation remains a potential strategy to remove eroded coils and their associated kidney stones; however, recurrent stone formation on the coil stump may necessitate repeat intervention if this conservative approach is pursued over radical antegrade coil removal. This case highlights the importance of continued surveillance and multidisciplinary management in preventing and treating coil erosion after PCNL