Characterizing the Impact of Women in Academic IR: A 12-Year Analysis 

Summary:

Historically, there has been a relative paucity of women in IR. A 2016 study demonstrated that only 15.4% of IR fellows and 7.3% of IR faculty were women. This disparity has led to inequalities in physician compensation, promotion, recruitment of female trainees and lack of female involvement in research. This study aimed to evaluate if there are gender disparities in the field of IR based on analysis of grants and citation data in both JVIR and CVIR.

A total of 3,017 articles were evaluated from 2006 to 2017 in which the gender of the first and last authors could be verified. Of this, a mere 16% of first authors and 8.7% of senior authors were female. Only 1.3% of articles were written by female first and senior authors while the overwhelming majority (77%) were by male first and senior authors. The mean number of citations received by all reviewed articles was 4.3, without statistical significance between gender combinations for both citations and grants. Over the 12 years reviewed, the average number of citations by both female first (0.24 per year) and senior (0.16 per year) authors increased; the average number of grants for female senior authors also increased by 0.88 per year.

While other specialties have demonstrated that men are viewed higher than women in regards to grade and compensation despite identical work, this article demonstrates that IR treats women equally. Female first and senior authorship are proportionally represented based on the number of women in the field, with women being equally productive as men based on metrics of number of publications, citations and grants.



Figure 1. Authorship by gender in the Journal of Vascular and Interventional Radiology and CardioVascular and Interventional Radiology. (a) Number and percentage of articles written by each gender. The predominance of male authors was more pronounced among senior authors than first authors (P < .01). (b) Number and percentage of articles written by each author gender combination. No difference was observed between expected and observed proportions of author gender combinations (P ¼ .99). *indicates P < .05.

Commentary:

While the proportion of women in IR can be intimidating, the data presented in this article is encouraging for females entering or currently in the field of IR. Many women cite gender disparity and the “glass ceiling” of academic medicine as reason to avoid male dominated specialties; this stance does not hold true in the field of IR. Not only are females proportionately represented in our literature, the trend of female authorship continues to increase, a promising result as the proportion of women entering the field continues to grow.

Click here for abstract

Xiao N, Oliveira DFM, Gupta R. Characterizing the Impact of Women in Academic IR: A 12-Year Analysis. J Vasc Interv Radiol. 2018; 29:1553-1557.

Post Author:
Nicole A. Keefe, MD
Resident Physician
Department of Radiology and Medical Imaging
University of Virginia
@NikkiKeefe

Para-Axial Central Venous Stent Placement in Patients with Malignant Central Venous Obstruction with a Venous Port 

Summary

Endovascular central venous stent (CVS) placement has been shown to improve symptoms and outcomes related to central venous obstruction. In patients with malignant central venous obstruction, preservation of previously placed indwelling port catheters is an important consideration during CVS placement. Previously, catheters were removed during CVS placement and replaced within the stent lumen to achieve an intra-stent configuration (i-CVS). This prospective cohort study explores the option of para-axial stent placement (p-CVS) which would obviate the need for removal and replacement of the port catheter. A total of 61 patients with malignant central venous obstruction were included in the study, of which 38 underwent p-CVS and 23 underwent i-CVS. Patients who had previously placed implanted port catheters underwent p-CVS placement. i-CVS placement was performed in all patients who had stents placed prior to port catheter placement. The authors defined successful stent and catheter placement as deployment of the central venous stent without port dysfunction or residual central venous stenosis on completion venography. Follow up chest radiography was used to evaluate for catheter fracture or stent migration. At 6 month follow up, none of the patients suffered from catheter dysfunction/fracture or stent migration. Follow up CT imaging revealed in-stent stenosis in 6/24 of the p-CVS patients and 6/18 of the i-CVS patients, a statistically insignificant difference (p = 0.33).



Figure. (a, b) Transverse CT image and plain chest film show the i-CVS placement state. The catheter (arrow) of the implanted venous port is located in the lumen of the stent. (c, d) Transverse CT image and plain chest film show the p-CVS placement. The catheter (arrow) of the implanted venous port is located between the stent and the vessel wall.

Commentary

The logistical challenges associated with placement of central venous stents in patients with previously placed port catheters have not been previously adequately addressed. Removal and re-implantation of central venous ports or repositioning of the catheter tip using a snare to achieve an intra-stent configuration exposes patients to increased complication risks and additional procedural costs. The authors propose an alternate solution of leaving the port catheter external to the lumen of the stent and were able to show no complications of stent migration or catheter dysfunction as a result of this configuration. The authors do not specifically comment on whether any dual-lumen catheters were used during the study but they do note that a limitation of the study was that small diameter ports were used during the study. Conceivably, use of larger diameter catheters such as dialysis catheters or even dual lumen ports during p-CVS placement could contribute to an increased rate of catheter dysfunction or stent migration. This question needs to be addressed in follow up studies to help determine whether this could be a viable option in patients with ESRD. Longer term follow up is also needed to assess for potential increased complications that could occur with p-CVS placement. Additionally, since only 1 of the para-axial port catheters had to be removed during the study, it is not currently known whether removal of these catheters is associated with increased rates of intra-procedural catheter fracture or stent migration. Nonetheless, this study provides substantial evidence that para-axial port placement in patients with central venous obstruction is a viable option.

Click here for abstract

Kim, Su Ho, et al. “Para-Axial Central Venous Stent Placement in Patients with Malignant Central Venous Obstruction with a Venous Port.” Journal of Vascular and Interventional Radiology, vol. 29, no. 11, Nov. 2018, pp. 1567–1570.

Post Author:
Shuaib Mohammad, MD
Department of Radiology
Wake Forest Baptist Medical Center
@WakeForest_IR

Catheter-Directed Thrombolysis for Portal Vein Thrombosis in Children: A Case Series

Summary

Pediatric portal vein thrombosis (PVT) in children has a high morbidity related to portal hypertension (PH). The current study retrospectively described the experience using catheter-directed thrombolysis (CDT) in the treatment of PVT within 10 consecutive children (mean age 11.9 years) undergoing 13 interventions. PVT confirmed via ultrasound or computed tomography was treated by first obtaining percutaneous transhepatic and/or transjugular intrahepatic portal access followed by placement of a transjugular intrahepatic portosystemic shunt (TIPS) in patients with PH. CDT consisted of intraprocedural tissue plasminogen activator (tPA) administration followed by mechanical thrombectomy, and if indicated, overnight thrombolysis.

Complete thrombolysis and partial thrombolysis was achieved in 7 (53.8%) and 3 (23.1%) cases, respectively. Two major complications occurred including hemoperitoneum requiring blood transfusion and right hemothorax requiring chest tube placement. Six patients (66%) did not have recurrent PVT on mean follow-up of 30.4 months. Regarding the remaining 3 patients; one developed cavernous transformation of the portal vein, one was found to have an occlusion of the left portal vein, and one developed recurrent thrombosis of the portal vein. CDT for PVT can be safely performed in children with similar recanalization rates to those recorded in literature for thrombolysis in PVT in adults.

Figure
Incremental response to CDT in a 15-year-old girl with PVT and superior mesenteric vein involvement. (a) Initial portal venogram from a PTH approach demonstrates extensive thrombus throughout the superior mesenteric vein with extension into the main, right, and left portal veins. (b) Follow-up portal venogram obtained after 36 hours of tPA infusion demonstrating partial lysis of PVT with decreased thrombus burden in the main portal vein but with continued extensive thrombus in the superior mesenteric vein. (c) Final portal venogram obtained after CDT in conjunction with TIPS placement demonstrating complete lysis of previously seen PVT.

Commentary

This case series represents the largest cohort of pediatric patients undergoing CDT for the treatment of PVT and attempts to establish the efficacy and safety of the procedure in this population.

Interestingly, both major complications occurred as a result of percutaneous transhepatic access. It would appear that utilization of the transjugular approach not only reduces the complication profile of the procedure, but also facilitates simultaneous TIPS placement in patients with PH. As access and familiarity with intravascular ultrasound expands, transjugular access for CDT within the portal system should become more efficient and safer.

All patient were discharged on twice-daily enoxaparin for a minimum of 3 months, with 2 patients receiving additional aspirin 81 mg daily. Given this younger population, consideration regarding long-term anticoagulation and the associated risks must be balanced with probability of developing recurrent PVT.

Currently, CDT in PVT in children appears to be a technically safe procedure with promising recanalization rates. Prospective studies with systematic procedural and follow-up imaging protocols are still required to fully understand the safety profile and long-term efficacy of this procedure.

Click here for abstract

Koo KSH, Lamar DL, Shaw DWW, Monroe EJ, Shivaram GM. Catheter-Directed Thrombolysis for Portal Vein Thrombosis in Children: A Case Series. Journal of Vascular and Interventional Radiology. 2018 Nov 1;29(11):1578–83.

Post Author:
Jacob Bundy, MD, MPH
PGY-1
Department of Surgery
University of Michigan Health System
@JBundyRad

Albumin-Bilirubin Score: An accurate Predictor of Hepatic Decompensation in High-Risk Patients Undergoing Transarterial Chemoembolization for Hepatocellular Carcinoma

Summary

Patient selection is a critical component within the decision paradigm in patients with hepatocellular carcinoma. Most interventional radiologists use total bilirubin values and Child-Turcotte-Pugh (CP) scores to aid in decision making. In fact, CP scores are one of four factors that comprise the Barcelona Clinic Liver Cancer (BCLC) classification, along with tumor extension, physical status, and cancer-related symptoms. However, the CP score was originally created to predict mortality following surgery in the cirrhotic population. Under BCLC recommendations, any CP class C patient is recommended for best supportive care, relegating a significant number of patients without a treatment option.

The albumin-bilirubin (ALBI) grade was created in 2015 as a purely objective assessment of underlying liver function. The goal of this study from the Stanford group was to identify predictors of acute-on-chronic liver failure (ACLF) following chemoembolization (TACE) and evaluating the use of ALBI grade as a predictor of ACLF in the high risk patients. The study evaluated patients with a CP score greater than or equal to 8 who underwent TACE. Patients were treated with both conventional TACE and drug-eluting-bead TACE. ALBI grades were designated as grade 1 if ≤ -2.60, grade 2 if > -2.60 but ≤ -1.39, and grade 3 if > -1.39. ACLF was reported at 30 days and 90 days following TACE using the chronic liver failure-sequential organ failure assessment algorithm.

ACLF occurred within 30 days in 8% of cases, with an additional 5% between 30 and 90 days. Significant predictors of ACLF or worsening ascites or encephalopathy at 90 days included bilirubin, albumin, and ALBI grade. ALBI score was the only remaining statistically significant variable following multivariate regression analysis. The authors concluded that TACe can be performed safely in patients with moderate to severe liver dysfunction and that ALBI score can help determine risk stratification.



Figure 2. Prediction curve from logistic regression model for ACLF at 90 days using ALBI scores showing the risk of ACLF is negligible for ALBI scores < -1.5, increases minimally when the ALBI score reaches -1.39 (ABLI grade 3), and increases rapidly as the ALBI score nears 0.

ALBI Score = (log10 bilirubin x 0.66) + (albumin x -0.085)
Bilirubin is in µmol/L and albumin in g/L.

Commentary

In the past three years, ALBI score has drawn a fair amount of attention within the interventional oncology world as a purely objective scale for predicting survival within cirrhotics with hepatocellular carcinoma. Patients with moderate and severe liver dysfunction and hepatocellular carcinoma have proven to be a challenging patient population. Following the BCLC algorithm, any patient with CP class C liver dysfunction is deemed terminal with recommendation for best supportive care. This study demonstrates the role of the ALBI score in aiding interventional radiologists in selecting which CP C patients are safe to TACE, with risk of ACLF increasing only when the ALBI score > -1. With using ALBI to determine which high risk patients have unacceptable morbidity and mortality risks following TACE, a significant population of CP C patients could now be offered treatment confidently. The impact would include improving overall survival with potential to down-stage patients to become transplant candidates or keep them transplant eligible. This paper adds to the existing literature supporting the use of ALBI score in not only survival prediction, but also risk stratification for ACLF and thus tumor board decision making and patient counseling.

Click here for abstract

Mohmammed M, Khalaf M, Liang T, et al. Albumin-Bilirubin Score: An Accurate Predictor of Hepatic Decompensation in High-Risk Patients Undergoing Transarterial Chemoembolization for Hepatocellular Carcinoma. J Vasc Interv Radiol. 2018; 29: 1527-1534.

Post Author:
David M Mauro, MD
Assistant Professor
Department of Radiology
Vascular and Interventional Radiology
University of North Carolina
@DavidMauroMD

Single-Center Retrospective Review of Radiofrequency Wire Recanalization of Refractory Central Venous Occlusions 

Summary

Recent retrospectively study reviewed the effectiveness and safety of radiofrequency (RF) wire recanalization of central venous occlusions (CVOs) and compared recurrent and nonrecurrent CVOs in terms of patient and occlusion characteristics. A total of twenty CVOs were treated in 18 patients including the superior vena cava (SVC), brachiocephalic veins, inferior vena cava and iliac veins. CVO traversal was first attempted with standard and advanced techniques before RF wire recanalization. Sixteen CVOs (80%) were successfully transversed and associated with symptom relief. SVC perforation into the pericardial space occurred in one patient, who recovered completely from the procedure. Primary CVO patency rate was 56% at a median follow-up of 14.1 months. Recurrent CVOs tended to be infradiaphragmatic (71% vs 12% for supradiaphragmatic; P = .02), longer (12.9 cm ± 10.0 vs 2.3 cm ± 1.3; P < .01), and associated with implanted venous stents, filters, or cardiac pacer/defibrillator leads (86% vs 22%; P = .01). Median time to restenosis/occlusion was 1.5 months. Follow-up with computed tomographic venography and clinic visits was performed approximately 1, 3, 6, and 12 months after treatment. The authors concluded that RF wire recanalization is a relatively effective and safe option for refractory CVOs. Longer, infradiaphragmatic CVOs associated with indwelling devices may require closer follow-up for CVO recurrence.



Figure 2. Recanalization of a refractory CVO involving a left common iliac vein stent in a 28-year-old woman with May–Thurner syndrome, an IVC filter, and multiple endovenous interventions. (a,b) Venograms from an outside hospital at which standard recanalization from caudal and cranial approaches had failed. (c) Advancement of an angled RF wire into the occlusion. (d) Posttreatment venogram shows resolution of the CVO.

Commentary

This paper presents further understanding of this previously described technique of sharp recanalization of CVO utilizing RF wire. We are all aware of the increasing incidence of CVO and how debilitating it can be to the patients. In addition, treatment of this condition is very challenging and pretty much limited to endovascular recanalization. In the present study the majority of the patients (80%) had technical and clinical success with only one major complication (SVC perforation) that resolved completely without further intervention. Infradiaphragmatic occlusions (iliac/IVC), longer occluded segments and presence of implanted devices (previous stents, IVC filter, defibrillator/pacemaker leads) were associated with higher incidence of recurrent stenosis/occlusion. As mentioned by the authors the study is limited by the small sample size and by the fact that all procedures were performed by a single operator, which may prevent reproducibility. Nonetheless, the research adds new knowledge regarding patient and lesion characteristics that may influence the outcome. This will certainly help interventionalists in their decision making process and to tailor more appropriate care for each patient. The study also highlights the need for further investigation on other methods of CVO recanalization and their potential associated predictive factors for recurrent stenosis/occlusion.

Keller EJ, Gupta SA, Bondarev S, Sato KT, Vogelzang RL, Resnick SA. Single-Center Retrospective Review of Radiofrequency Wire Recanalization of Refractory Central Venous Occlusions. Journal of Vascular and Interventional Radiology. 2018 Nov 1;29(11):1571-7.

Click here for abstract

Post Author:
Ricardo Yamada, MD
Assistant Professor
Department of Radiology
Division of Vascular and Interventional Radiology
Medical University of South Carolina

Safety of Radioembolization in the Setting of Angiographically Apparent Arterioportal Shunting

Summary

The authors retrospectively evaluated all patients that underwent radioembolization for the treatment of HCC that also demonstrated angiographically apparent arterioportal shunting and investigated the association of adverse events with the different types of shunts. The authors divided the shunts into segmental, ipsilobar, contralobar and main lobar. Patients were excluded if the patients had undergone shunt mitigation techniques, had non-HCC liver malignancies or extrehepatic HCC, as well as insufficient follow up.

32 patients with 34 administrations were included with a median Na-MELD of 8.5. Patients underwent lobar and segmental treatments with >120 Gy and <120 Gy. Both glass and resin spheres were used. 28% of tumors were solitary, 22% multifocal and 50% infiltrative. 22% of patients were BCLC A, 12% B, 60% C and 6% D. Segmental shunts were seen in 35% of cases, ipsilobar 41%, contralobar 18% and main portal in 6%. Adverse events were graded using CTCAE version 4.0, and were considered significant if they were grade 3 or higher. The authors also analyzed CP class, ALBI grade, prior systemic chemotherapy, shunt direction and distribution, lobar vs. segmental dose administration and imaging of vascular invasion.

The authors found a statistical worsening of the ALBI score and a non-statistically significant trend to worsening of MELD and Na-MELD. A total of 15 AE were encountered, 7 of which were grade 3 or higher (22% clinically significant AEs). Radiation induced Liver Disease (ReILD) occurred in 4 patients, that showed lab abnormalities between 4-8 weeks, and death between 2-6 months. All ReILD cases were BCLC-C, underwent lobar administration and showed non-segmental shunts. This subgroup of patients had an AE rate of 38%, while the remainder of the cohort demonstrated AE rate of 12%. Response rates were higher for patients that presented with segmental shunts with 73% CR and 27% partial response. The overall survival for the cohort was 72% and 57% at 6 and 12 months respectively.

The authors found that all clinically significant AEs occurred in patients with non-segmental shunts. Furthermore, ReILD was seen in patients that presented with the triad of BCLC-C, non-segmental shunts and lobar Y90 administrations. A trend towards increased AEs was seen in patients that possessed this tried, with a clinically significant AE rate of 38%. No AE were seen in the resin Y90 patients, which the authors hypothesize could be due to the small sample of resin patients, the larger particle size or the lower dose when compared to glass spheres.

As far as response rates, both overall survival and initial response rates were similar to the current published outcomes.

The limitations of this study include the small sample, retrospective nature of the study and the heterogenous imaging follow up where MRI and CT were used.

The authors conclude that radioembolization in the setting of arterioportal shunting showed a variable safety profile. In one hand, segmental shunts appear to be well tolerated. On the other hand, caution should be taken in patients with advanced HCC stage, non-segmental shunts that undergo lobar administrations where clinically significant AEs were seen 38% of the time.



Figure- Early (1) and late (b) injection of the left hepatic artery demonstrates fugal shunting into the main portal vein (red arrows). (c) Demonstrates filling of the portal vein (yellow arrow) on the arterial phase scan.

Commentary

The authors found that radioembolization appears to be safe and effective in HCC patients with angiographically apparent segmental shunts. While BCLC-C patients with non-segmental shunts that undergo lobar treatment are at higher risk for clinically significant AEs, including ReILD. More studies are necessary to validate the imaging outcomes and survival in this patient cohort, as well as the safety of resin spheres in patients with AP shuts, that in this study did not show any AEs.

Click here for abstract

Thornton LM, Geller BS, Pepin EW, Shah JL, Kapp M, Toskich BB. Safety of Radioembolization in the Setting of Angiographically Apparent Arterioportal Shunting. J Vasc Interv Radiol. 2018 Nov;29(11):1511-1518. doi: 10.1016/j.jvir.2018.06.012. Epub 2018 Oct 5. PubMed PMID: 30293727

Post Author:
Carlos J. Guevara, MD
Assistant Professor
Department of Radiology, Interventional Radiology Division
University of Texas Health Sciences, Houston
@CarlosGuevaraIR
@UTHouston_IR

Chemoembolization in Conjunction with Bevacizumab: Preliminary Results

Summary

“The whole is greater than the sum of its parts” – SYNERGY! This is a concept that has been utilized a lot in oncology and modern medicine. Interventional oncology is no exception especially as new cancer treatment options continue to emerge. What we have lacked however, is the robust evidence to support this concept in our blossoming interventional oncology sphere.

In a recently published proof of concept paper, researchers from Italy and Slovenia published their preliminary results for chemoembolization in combination with Bevacizumab in colorectal liver metastasis (CR-LM). In this prospective observational single center trial, 6 patients with unresectable CR-LM that were naïve to standard chemotherapy and had good performance status (ECOG 0 and 1).

The patients received two cycles of DEB-IRI chemoembolization using the PEG embolic delivery platform loaded with 100 mg irinotecan. Bevacizumab was initiated 15 days after the first chemoembolization and then biweekly for a total of 8 cycles. OS, PFS, TTP, mRECIST tumor response, adverse effects and QoL were measured.

At 3 months: 2 pts (33%) CR, 2 pts (33 %) PR, 1 pt (17%) SD and 1 patient progressed (patient had advanced disease and on 4th line chemotherapy). Median overall survival (OS) was 10 months (range 7–15 months), median time to progression was 3 months (range 2–5 months), and median progression-free survival was 7 months (range 3–15 months). There was a reported increase in quality of life in 4 patients (66%)

There were no complications during chemoembolization but mild to moderate adverse events related to post chemoembolization syndrome were reported. Bevacizumab related adverse effects were hypertension (17%) and skins rash (33%).



Figure 1. Tumor response at 1, 3, and 6 months after first transarterial chemoembolization. CR = complete response; PD = progressive disease; PR = partial response; SD = stable disease.

Commentary

Exploiting increased expression of VEGF post chemoembolization to create synergistic localized oncologic benefits was demonstrated with (Hepatocellular carcinoma) HCC where locoregional chemoembolization has had a very significant role over the last 3 decades. We have limited clinical data that this concept is also clinically beneficial to patients with CRC-LM.

Hepatocellular carcinoma tends to be hypervascular and largely depends on the hepatic arterial tree vs CRC - LM which are generally hypovascular and largely depend on portal venous circulation. The impact of these potential perfusion differences on the concept and ability to translate to meaningful clinical benefit or difference is still not known. This paper provides a platform and basis for us to continue to investigate this potentially beneficial option to patients and exciting frontier for interventional oncology.

The median OS of 10 months in this very small cohort is lower than previously published median OS of 14 months with DEB-IRI alone. It is important to note the study recruited technically the “worst” responders with >3 failed lines of systemic chemotherapy and attenuated expected OS. The 3 months mRECIST tumor control rates appeared comparable with previous trials of all comers. Therefore, the preliminary results suggest a very interesting trend which is potentially beneficial to patients with advanced CRC-LM.

This sets an excellent foundation for expanding this to larger multicenter cohorts to validate this concept in chemo naïve CRC-LM and also to perhaps consider trials that extend this concept to early treatment lines for CRM-LM.

The study has multiple weaknesses, not least: sample size, single center, lack of control group, no randomization to name a few. The authors do a good job to acknowledge these and many more.

Click here for the abstract

Fiorentini G, Sarti D, Aliberti C, Carandina R, Mulazzani L, Felicioli A, Guadagni S. Chemoembolization in Conjunction with Bevacizumab: Preliminary Results. J Vasc Interv Radiol. 2018 Sep;29(9):1236-1239. doi: 10.1016/j.jvir.2018.04.022. PubMed PMID: 30146190.

Post Author:
Rodrick C Zvavanjanja MD, MSc, FRCR, DABR(VIR/DR)
Assistant Professor
Department of Diagnostic and Interventional Radiology
University of Texas at Houston McGovern Medical School
@RodZvavanjanja

Association of PI3K Pathway Mutations with Early Positron-Emission Tomography/CT Imaging Response after Radioembolization for Breast Cancer Liver Metastases: Results of a Single-Center Retrospective Pilot Study 

Summary

Metastatic breast cancer remains a leading cause of cancer death in women and predictors of response to hepatic metastases treated by radioembolization have not been well established.

The authors of this retrospective review sought to describe the response and survival after radioembolization with a focus on pathways affecting radiation sensitivity. They performed a retrospective review of 31 patients who had undergone radioembolization for metastatic invasive ductal carcinoma to the liver. No patient underwent external radiation to the liver or previous transarterial therapy and all but 2 patients had multifocal liver disease. In addition, all patients had received at least 3 lines of systemic therapy prior to radioembolization. Twenty-four patients underwent genetic profiling before radioembolization, with tumor tissue specimens obtained from various sites. Twenty-two patients were treated with resin spheres and 9 were treated with glass spheres with 14 patients undergoing treatment of both hepatic lobes and the remaining patients receiving unilobar or segmental treatments. Imaging response was assessed on PET/CT imaging with the changes in SUVmax evaluated. Among the 26 patients with PET/CT imaging before and after radioembolization, 18 had complete or partial imaging response and 8 did not respond. Genetic profiling was available in 24 patients with 21 patients having both genetic profiling and imaging available. Of these 21 patients, 15 had a response (complete or partial) and 6 did not respond. Radiographic response was found to be significantly associated with PI3K mutations but not MAPK/ERK or TP53 mutations or HER2 receptor status; only 5 of 11 of PI3K wild-type patients (45%) had an imaging response, but all 10 with PI3K mutations showed a response. Furthermore, complete or partial response by PET/CT at 2– 4 months was associated with significantly longer median survival (967 d) compared with patients without imaging response (291 d).



Figure 2. Kaplan–Meier survival analysis of all patients in the cohort demonstrates a median survival of 10.9 months after radioembolization.

Commentary

The researchers found that P13K pathway mutations are associated with early imaging response after radioembolization of metastatic breast cancer to the liver and that imaging response is associated with prolonged survival. While a relatively small sample size was studied, this study adds to our knowledge of genomic profiling as it relates to radioembolization outcomes. The ultimate goal is to optimize patient selection for our therapies and this work represents important progress in that direction.

Click here for abstract

Deipolyi, Amy R. et al. Association of PI3K Pathway Mutations with Early Positron-Emission Tomography/CT Imaging Response after Radioembolization for Breast Cancer Liver Metastases: Results of a Single-Center Retrospective Pilot Study. Journal of Vascular and Interventional Radiology, Volume 29, Issue 9, 1226–1235.

Post Author: 
Zagum Bhatti, MD
Assistant Professor
Department of Radiology, Interventional Radiology Division
University of Texas Health Science Center at Houston, Houston, TX
@UTHouston_IR
@ZagumBhatti

Comparison of Radiofrequency Ablation and Hepatic Resection for the Treatment of Hepatocellular Carcinoma 2 cm or Less 

Summary

A retrospective analysis to compare the survival outcomes after Radiofrequency ablation (RFA) verses Surgical resection(SR) for Hepatocellular cancer(HCC) measuring ≤ 2cm was undertaken. The National Cancer Database was the source. 833 patients with tumors measuring between 5 and 20 mm who underwent either RFA or SR between 2004 and 2014 were included. 620(74.4%) received RFA and 213 (25.6%) received SR. Mean age 60, median tumor size 15mm, 70.1% males, 61% Caucasians, 42.3 with no comorbidities. Demographic and tumor characteristics between the 2 cohorts were compared using the student’s t test for continuous variables and Chi Square test for categorical variables. Log regression was used to determine variables governing choice of treatment, Kaplan Meier analysis and log rank test were used to compared overall survival (OS). A 2 sided P value of < 0.05 was considered significant.

Median follow up was 33.6 months-32.9 for RFA and 35.4 months for SR. The only factor which showed statistical significance regarding how patients were selected for RFA vs SR was a MELD score of >9. Median OS for the entire cohort was 62.7 months (95% CI 50.6-74.8).1,3 and 5-year survival RF group was 90%,64%,47% and the SR group 89%,75%,62%. SR was not associated with longer OS with HR 0.758(CI 0.538-1.068, P .113). OS was longer with multivariate regression analysis for female gender, African American or Asian ethnicity and median income ≥ $48,000 and shorter for higher MELD scores.



Figure 2. Kaplan-Meier curves of patients who received RF ablation and SR (a) before and (b) after propensity score matching. Dotted lines represent 95% confidence intervals.

Commentary

The authors have tried to address the question whether RFA and SR are comparable for small HCCs. Several studies in the past have given conflicting conclusions. The unique feature of this study is source of the data. The national database has a larger number of patients with diverse backgrounds in terms of ethnicity, etiologies and liver functions. The size criteria are stricter and there is an attempt to compare apples to apples with inclusion of just RFA and no other ablative modalities unlike previous studies. The authors used MELD score to represent liver functions and included all comers not just BCLC A patients. They did not find any difference in OS. The authors also compared the influence of gender, ethnicity, income and liver functions on OS for the entire cohort. They found better prognosis for female gender, African American or Asian ethnicity, higher socioeconomic strata and poorer prognosis for higher MELD scores. The study limitations include its retrospective nature. No information on Child Score, specific etiology, local recurrence rate, complications, recurrence free survival, effect of location of the tumor was available. Also the group studied will not meet the LIRADs criteria of LR5 for HCC due to the size criteria making the diagnosis of HCC questionable. MELD was a determining factor in choosing the treatment option and could be interpreted as the RFA cohort had poorer liver functions. Yet the survival was comparable. The effect of treating sicker patients and having comparable outcome favors RFA to SR. Overall survival is not a great end point in isolation for these small tumors and early HCC as the natural history of these tumors may not be affected by the treatment.

Click here for abstract

Huang Y, Shen Q, Bai HX, et al. Comparison of Radiofrequency Ablation and Hepatic Resection for the Treatment of Hepatocellular Carcinoma 2 cm or Less. J Vasc Interv Radiol 2018; 29:1218-25 e2.

Post Author:
Anil K Pillai, MD
Associate Professor and Section Chief,
University of Texas Health Science Center
@AnkupiMD

One-Year Analysis of the Prospective Multicenter SENTRY Clinical Trial: Safety and Effectiveness of the Novate Sentry Bioconvertible Inferior Vena Cava Filter

Summary

Complications associated with Inferior Vena Cava (IVC) filters including Caval thrombosis, device tilting, fracture, migration, embolization, IVC perforation and death are well established and occur with increasing frequency with longer filter indwelling time. Unfortunately, despite increased awareness and filter follow up initiatives, as many as 65-80% of retrievable filters remain in place. The Sentry (Novate Medical, Galway, Ireland) IVC filter is designed to provide temporary protection against PE during transient high-risk periods and then bioconvert, avoiding the need for a second (retrieval) intervention and leaving behind a patent IVC lumen. Bioconversion occurs after approximately 60 days with hydrolysis of an absorbable filament that holds the filter arms together, allows them to retract against the IVC wall.  

This is a prospective, multi-center evaluation including 23 sites and 129 patients from the United States, Belgium and Chile. Early experience with the Sentry IVC filter, including safety and efficacy of the device and success with subsequent bioconversion were studied. Patients included were those with deep vein thrombosis or PE, or at temporary risk for venous thromboembolism and PE who could not use anticoagulation. The primary end point was clinical success, including filter deployment, freedom from new symptomatic PE before filter bioconversion at 60 days and filter related complications.  

Clinical success was achieved in 111 of 114 patients. There were no new cases of PE identified through 12 months of follow up. 2 patients developed symptomatic IVC thrombosis within the first month, which did not recur after successful intervention. There were no filter related complications through 12 months. Filter bioconversion was successful in 110/115 patients (95.7%) at 6-months and 106/100 patients (96.4%) at 12-months.

Figure 1
Photographs of the Sentry IVC filter in coronal view and representations of the axial view: (left) filtering configuration; (right) bioconverted configuration. In the filtering configuration, the 6 pairs of filter arms are held together in the center of the lumen by means of the bioabsorbable filament composed of poly-p-dioxanone. In the bioconverted configuration, the bioabsorbable filament will have been degraded via hydrolysis, allowing the filter arms to release from the cone and retract toward the IVC wall to be endothelialized, leaving an unobstructed IVC lumen.  

Commentary

This prospective, multi-center single arm evaluation of the bioconvertible Sentry filter is an interesting early experience with this device. The complications of IVC filters are widely established and even with a push towards aggressive follow up and filter retrieval, a large proportion of filters remain in place. This bioconvertible device negates the need for a second retrieval procedure in that automatic filter conversion occurs after approximately 2 months, leaving an intact IVC lumen. One potential downside of the device is that the filter does in fact remain in place in the patient’s IVC following bioconversion and so long-term patency and changes in IVC diameter at this level, as well as other potential complications will need extended evaluation. The authors reported that this will be addressed at the 24-month follow up as CT venography will be performed at that time. Additionally, patients who develop a new indication for IVC filtration following bioconversion could be an interesting point of discussion. Does the bioconverted device endothelialize to a point allowing subsequent filter placement at that level or does a new filter need to be placed above or below the bioconverted device, as was done in 2 patients in this study? Some self-reported limitations include its non-randomized, single-arm design as well as the inherent potential bias of a manufacturer funded regulatory device trial. Overall the safety and efficacy of this device appear to be acceptable and in-line with retrievable IVC filters that are available. Bioconversion rates are high and this novel IVC filtration option may prove to be ideal for some patients.   

Click here for abstract

Dake M, Murphy T, Kramer A, Darcy M, Sewall L, Curi M, Johnson M, Arena F, Swischuk J, Ansel G, Silver M, Saddekni S, Brower J, and Mendes R. One Year Analysis of the Prospective Multicenter SENTRY Clinical Trial: Safety and Effectiveness of the Novate Sentry Bioconvertible Inferior Vena Cava Filter. J Vasc Interv Radiol. 2018 Oct;29(10):1350-1361

Post Author:
Jordan Tasse, MD
Assistant Professor, Vascular and Interventional Radiology
Associate Program Director, Integrated VIR residency and VIR fellowship programs
Rush University Medical Center, Chicago, IL
Email: Jordan_C_Tasse@Rush.edu
Twitter: @JTassMD, @VIR_RUSH