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Hepatocellular carcinoma (HCC), the most common primary liver cancer, of which ∼800 000 new cases will be diagnosed worldwide this year, portends a five-year survival rate of merely 17% in patients with unresectable disease. This dismal prognosis is due, at least in part, from the late stage of diagnosis and the limited efficacy of systemic therapies. As a result, there is an urgent need to identify risk factors that contribute to HCC initiation and provide targetable vulnerabilities to improve patient survival. While myriad risk factors are known, elevated copper (Cu) levels in HCC patients and the incidence of hepatobiliary malignancies in Wilson disease patients, which exhibit hereditary liver Cu overload, suggests the possibility that metal accumulation promotes malignant transformation. Here we found that expression of the Cu transporter genes ATP7A, ATP7B, SLC31A1, and SLC31A2 was significantly altered in liver cancer samples and were associated with elevated Cu levels in liver cancer tissue and cells. Further analysis of genomic copy number data revealed that alterations in Cu transporter gene loci correlate with poorer survival in HCC patients. Genetic loss of the Cu importer SLC31A1 (CTR1) or pharmacologic suppression of Cu decreased the viability, clonogenic survival, and anchorage-independent growth of human HCC cell lines. Mechanistically, CTR1 knockdown or Cu chelation decreased glycolytic gene expression and downstream metabolite utilization and as a result forestalled tumor cell survival after exposure to hypoxia, which mimics oxygen deprivation elicited by transarterial embolization, a standard-of-care therapy used for patients with unresectable HCC. Taken together, these findings established an association between altered Cu homeostasis and HCC and suggest that limiting Cu bioavailability may provide a new treatment strategy for HCC by restricting the metabolic reprogramming necessary for cancer cell survival.

In this study, we describe new methods for studying cancer cell metabolism with hyperpolarized 13C magnetic resonance spectroscopy (HP 13C MRS) that will enable quantitative studies at low oxygen concentrations. Cultured hepatocellular carcinoma cells were grown on the surfaces of non-porous microcarriers inside an NMR spectrometer. They were perfused radially from a central distributer in a modified NMR tube (bioreactor). The oxygen level of the perfusate was continuously monitored and controlled externally. Hyperpolarized substrates were injected continuously into the perfusate stream with a newly designed system that prevented oxygen and temperature perturbations in the bioreactor. Computational and experimental results demonstrated that cell mass oxygen profiles with radial flow were much more uniform than with conventional axial flow. Further, the metabolism of HP [1-13C]pyruvate was markedly different between the two flow configurations, demonstrating the importance of avoiding large oxygen gradients in cell perfusion experiments.

RATIONALE AND OBJECTIVES: In response to the COVID-19 pandemic reducing medical student presence on clinical services and in classrooms, academic institutions are utilizing a virtual format to continue medical student education. We describe a successful initial experience implementing a virtual elective in interventional radiology (IR) and provide the course framework, student feedback, and potential improvements. MATERIALS AND METHODS: A 2-week virtual IR elective curriculum was created utilizing a combination of synchronous and asynchronous learning and the "flipped" classroom educational model. Students virtually participated in daily IR resident education conferences, resident-led case review sessions, and dedicated lectures. Asynchronous prelearning material consisted of text and video correlating to lecture topics. Anonymous precourse and postcourse surveys were sent to all participating students (n = 10). RESULTS: Ten students (100%) completed precourse and seven (70%) completed postcourse surveys. Enrolled students were considering residencies in surgery (50%), internal medicine (40%), interventional radiology (30%), and/or diagnostic radiology (30%). Students' understanding of what IRs do and the procedures they perform (p < 0.001), when to consult IR for assistance in patient management (p = 0.005), and the number of IR procedures students could recall (p = 0.015) improved after the course. Case-review sessions and virtual lectures ranked as having the highest education value. Students recommended additional small-group case workshops. CONCLUSION: This successful virtual IR elective provides a framework for others to continue IR medical student education during the pandemic and grow the specialty's presence within an increasingly virtual medical school curriculum. The described model may be modified to improve IR education beyond the COVID-19 era.

Background and aims Advances in cancer treatment have improved survival; however, local recurrence and metastatic disease-the principal causes of cancer mortality-have limited the ability to achieve durable remissions. Local recurrences arise from latent tumor cells that survive therapy and are often not detectable by conventional clinical imaging techniques. Local recurrence after transarterial embolization (TAE) of hepatocellular carcinoma (HCC) provides a compelling clinical correlate of this phenomenon. In response to TAE-induced ischemia, HCC cells adapt their growth program to effect a latent phenotype that precedes local recurrence. Approach and results In this study, we characterized and leveraged the metabolic reprogramming demonstrated by latent HCC cells in response to TAE-induced ischemia to enable their detection in vivo using dynamic nuclear polarization (DNP) magnetic resonance spectroscopic imaging (MRSI) of 13 carbon-labeled substrates. Under TAE-induced ischemia, latent HCC cells demonstrated reduced metabolism and developed a dependence on glycolytic flux to lactate. Despite the hypometabolic state of these cells, DNP-MRSI of 1-13 C-pyruvate and its downstream metabolites, 1-13 C-lactate and 1-13 C-alanine, predicted histological viability. Conclusions These studies provide a paradigm for imaging latent, treatment-refractory cancer cells, suggesting that DNP-MRSI provides a technology for this application.

Clear cell chondrosarcoma (CCCS) is a rare variant of conventional chondrosarcoma with low-grade malignant features that may be confused radiographically and histologically with chondroblastoma. We report a case of a 50-year-old female who presented with 6 months of left hip pain. Initial radiographs demonstrated an osteolytic lesion with adjacent area of sclerosis in the proximal left femur. Magnetic resonance imaging demonstrated a marrow-infiltrative lesion with periosteal reaction and thickened enhancing periosteum. Biopsy of the sclerotic area demonstrated chondroblastoma-like findings, whereas biopsy of the lytic area showed features suggestive of CCCS. The patient eventually underwent en bloc resection and reconstruction with a proximal femoral megaprosthesis. The final diagnosis was CCCS. We present this unusual case with review of the radiographic and histologic features of CCCS with attention to its ability to mimic chondroblastomas. This case highlights the importance of sampling radiographically heterogeneous areas within a bone lesion to facilitate accurate diagnosis and appropriate management.

To characterize and compare the experiences of matched applicants and program directors (PDs) participating in the first large-scale integrated interventional radiology (IR) residency match.Survey questionnaires were distributed nationally to integrated IR applicants who matched in the 2017 Match cycle and PDs. Both groups were questioned regarding their experiences with the application, interview, rank, and match processes as well as applicant-specific and PD-specific information. Summary and descriptive statistics were applied to responses, and comparison of Likert scale responses was performed by two-sample t test.Sixty-one matched applicants (51.3%) and 34 PDs (55.7%) responded to the survey. Regarding the match process, applicants believed United States Medical Licensing Examination (USMLE) Step 1 score (P = .002) and connection to a program's geographic location (P = .006) were significantly more important than PDs did, whereas PDs ranked grades (P = .049), class rank (P = .011), academic awards (P = .003), additional degrees (P.001), and USMLE Step 2 Clinical Skills score (P.001) as significantly more important factors than applicants did. Additional information regarding demographic data, medical school experiences in IR, application strategies, interview experiences, rank lists, the intern year, and match results are reported.The completion of the first large-scale integrated IR match represents a paradigm shift in the way in which IR practitioners are recruited and trained. This study provides valuable benchmark data and analysis that can be used to improve efforts to match the best-fitting applicants into the integrated IR residency and improve future match cycles for applicants and PDs alike.

To compare medical student knowledge of and interest in interventional radiology (IR) before and after the integration of an IR lecture series within the gross anatomy course.Four elective IR lectures were scheduled to coincide with the relevant anatomy dissection curriculum. Anonymous surveys were distributed to 146 students before and after the lectures regarding students' knowledge of and interest in IR, responsibilities of an IR physician, and IR training pathways. Those who did not attend served as controls.Response rates were 67% (n = 98) in the prelecture group, 55% (n = 22) in the group who attended the lecture, and 28% (n = 30) in the control group. A total of 73% of the prelecture group reported little knowledge of IR compared with other specialties. This decreased to 27% in those who attended the lecture (P.001). A total of 32% of those who attended believed they had more knowledge of IR than any other specialty, compared with 7% of controls (P value not significant) and 2% of the prelecture group (P .001). Those in attendance could name a significantly greater number of IR procedures (mean, 1.82) than the prelecture group (mean, 0.57; P.001). A total of 64% of those who attended would consider a career in IR, compared with 24% in the prelecture group and 33% in the control group (P.05). A total of 68% of those who attended had knowledge of the IR residency, compared with 5% in the prelecture group and 33% in the control group (P.05).Integration of IR education into the gross anatomy course proved to be a highly effective way of teaching preclinical students about IR and generating interest in the field.

PURPOSE: To characterize the angiographic and cross sectional imaging anatomy of the rat visceral vasculature in two translational models. MATERIALS AND METHODS: Animal studies were conducted in accordance with institutional guidelines and approval of the Institutional Animal Care and Use Committees. Retrospective review of digital subtraction arteriography was performed in 65 Wistar and 50 Sprague-Dawley male rats through a left common carotid artery or right common femoral artery approach. Magnetic resonance imaging of the abdomen was performed on these rats to correlate imaging modalities. RESULTS: Aortography was performed in three locations including cranial to the celiac artery, cranial to the renal arteries, and cranial to the caudal (inferior) mesenteric artery enabling characterization of the visceral branch arteries in all 65 Wistar rats. Selective arteriography of first, second and/or third order branch vessels of the aorta was performed allowing characterization of normal and variant anatomy. Dedicated selective arteriography of the celiac artery was performed in 65 Wistar and 10 Sprague-Dawley rats, of the common hepatic artery in 65 Wistar and 50 Sprague-Dawley rats, and of the cranial mesenteric artery in 43 Wistar rats. Magnetic resonance imaging enabled correlation with the lobar and portal venous anatomy. CONCLUSIONS: Analysis of arteriography and magnetic resonance imaging in these rat models will provide translational researchers with anatomic details needed to develop new endovascular protocols for small animal research in interventional radiology.

Accurately detecting inferior vena cava (IVC) filter complications is important for safe and successful retrieval as tip-embedded filters require removal with non-standard techniques. Venography prior to IVC filter retrieval has traditionally used a single anterior–posterior (AP) projection. This study compares the utility of rotational venography to AP venography prior to IVC filter removal. The rotational venograms from 100 consecutive IVC filter retrievals over a 35-month period were evaluated retrospectively. The AP view of the rotational venogram was examined separately from the full series by a radiologist blinded to alternative imaging and operative findings. The venograms were evaluated for tip embedding, filter fracture, filter thrombus, and IVC thrombus. Statistical analysis was performed. Using operative findings and peri-procedural imaging as the reference standard, tip embedding occurred in 59 of the 100 filters (59 %). AP venography was used to correctly identify 31 tip-embedded filters (53 % sensitivity) with two false positives (95 % specificity) for an accuracy of 70 %. Rotational venography was used to correctly identify 58 tip-embedded filters (98 % sensitivity) with one false positive (98 % specificity) for an accuracy of 98 %. A significant difference was found in the sensitivities of the two diagnostic approaches (P

Although benign, renal angiomyolipoma (AML) may lead to serious complications without appropriate management. The purpose of this review is to describe the role of and evidence for interventional radiology techniques in the management of patients with AML. For patients with renal masses and non-diagnostic imaging studies, image-guided percutaneous biopsy is found to be highly accurate and useful in directing patient management. Once the diagnosis of AML has been made based on either imaging or biopsy, arterial embolization of tumors that are symptomatic or >4 cm has been demonstrated to reduce the risk of hemorrhage as well as tumor size. Percutaneous ablation devices have been proposed as alternative strategies but remain investigational. The utility of interventional radiology techniques including percutaneous core needle biopsy and prophylactic super-selective arterial embolization is safe and effective management strategies for patients presenting with AML tumors.

Purpose To test the hypotheses that ( i ) heavier rats demonstrate improved survival with diminished fibrosis in a diethylnitrosamine (DEN)-induced model of hepatocellular carcinoma (HCC) and ( ii ) transarterial embolization via femoral artery access decreases procedure times versus carotid access. Materials and Methods One hundred thirty-eight male Wistar rats ingested 0.01% DEN in water ad libitum for 12 weeks. T2-weighted magnetic resonance imaging was used for tumor surveillance. Rats underwent selective embolization of ≥ 5 mm tumors via carotid or femoral artery catheterization under fluoroscopic guidance. Rats were retrospectively categorized into 3 groups by initial weight ( 400 g) for analyses of survival, tumor latency, and fibrosis. Access site was compared relative to procedural success, mortality, and time. Results No significant differences in tumor latency were related to weight group ( P = .310). Rats weighing P 400 g median, 1.0; P = .015). No significant difference was found in periprocedural mortality based on access site; however, procedure times were shorter via femoral approach (mean, 71 ± 23 vs 127 ± 24 min; P Conclusions Greater initial body weight resulted in improved survival without prolonged tumor latency for rats with DEN-induced HCCs and was associated with less severe fibrosis. A femoral approach for embolization resulted in decreased procedure time. These modifications provide a translational animal model of HCC and transarterial embolization that may be suited for short-term survival studies.

To the editor, We appreciate the interest of Jia et al. in our article ‘‘The Value of Rotational Venography Versus Anterior-Posterior Venography in 100 Consecutive IVC Filter Retrievals’’ [1]. Because this was not a surgical or necropsy-based study, an embedded filter tip was defined in our study by a composite reference of the standard imaging definition of lack of contrast around the filter tip along with the operative findings encountered during filter removal that required removal with endobronchial forceps. We feel this is a far more accurate definition compared with the timeand tiltbased definition proposed by the authors of the letter. Further, we prefer an evidence-based definition to a conjectural one. It has been elegantly shown that filter components can become embedded within 30 days [2] and likely sooner, given that the process of development of intimal hyperplasia in foreign bodies such as stents and filters begins immediately; one recent study of coronary stents showed [90 % strut coverage by 2 weeks [3]. The authors of the letter suggest, without any evidentiary basis, that 15 days is the minimum time needed to have a tip embedded filter. Given that there are no data to support this time-based definition, coupled with evidence in the literature to the contrary, their assertion that a filter removed at 11 days cannot be tip embedded is untenable. We thank Jia et al. for their interest in our work and appreciate the opportunity to further discuss the issue they raised. The issue raised by their letter, however, is not central to the importance of this study. The mean dwell time for filters in our study was 448 days and only 1 was removed at 11 days. Rotational venography can help interventionalists plan an appropriate approach to filter removal and avoid unsuccessful attempts to remove tipembedded filters using standard techniques which can occur if only AP venography is used. We stand by the conclusion of our study that ‘‘rotational venograms allow for more accurate detection of tip-embedded IVC filters compared to AP views alone.’’ Sincerely, S. William Stavropoulos, MD Scott O. Trerotola, MD Ryan M. Kiefer