Thoracic Duct Embolization Using Transabdominal Antegrade and Transcervical Retrograde Accesses

PurposeTo evaluate the technical success and clinical outcomes of thoracic duct embolization (TDE) using transabdominal antegrade and transcervical retrograde accesses to treat patients with chyle leak.Materials and MethodsThis study was a retrospective, nonblinded, single-institution chart review of all patients aged 18 years or older over a 6-year time frame who underwent lymphangiography with attempted TDE for iatrogenic or spontaneous chyle leaks using transabdominal antegrade and/or transcervical retrograde accesses.ResultsNinety-nine patients underwent 113 procedures. Eighty-five patients underwent 1 procedure, and 14 patients required 2 procedures. The technical success rate of TDE was 68% (72/106) with transabdominal antegrade access and 44% (15/34) with transcervical retrograde access. The overall technical success rate of TDE, including both the access methods, was 77% (87/113). The most common reasons for transabdominal access failure were small caliber of the cisterna chyli and thoracic duct (TD) occlusion. Five patients were lost to follow-up. Overall clinical success, defined as resolution of the chyle leak, was achieved in 83% (78/94) of the patients. There were 6 Society of Interventional Radiology (SIR) level 1 adverse events (AEs), 5 SIR level 2 AEs, and 2 SIR level 3 AEs. Nontarget embolization occurred in 2 patients.ConclusionsAlthough transcervical retrograde TDE is a challenging procedure, with a lower technical success rate than transabdominal antegrade access, retrograde access improved the technical and clinical success rates of the treatment of chyle leaks in cases of thoracic duct occlusion, small cisterna chyli, and leaks located in the abdomen.     

Safety and Efficacy of Retrograde Pyeloperfusion for Ureteral Protection during Renal Tumor Cryoablation

PurposeTo determine safety and efficacy of retrograde pyeloperfusion for ureteral protection during cryoablation of adjacent renal tumors.Materials and MethodsRetrospective review of 155 patients treated with renal cryoablation, including adjunctive retrograde pyeloperfusion, from 2005 to 2019 was performed. Ice contacted the ureter in 67 of the 155 patients who represented the study cohort. Median patient age was 68 years old (interquartile range [61, 74]), 52 patients (78%) were male, and 37 tumors (55%) were clear cell histology. Mean tumor size was 3.4 ± 1.3 cm, and 42 tumors (63%) were located at the lower pole. Treatment-related complication and oncologic outcomes were recorded based on a review of post-procedural images and chart review.ResultsTechnical success of cryoablation was attained in 67 cases (100%), and technical success of pyeloperfusion was attained in 66 cases (99%). A total of 13 patients (19.4%) experienced SIR major C or D complications related to the procedure, including hemorrhage (n = 4), urine leak (n = 3), transient urinary obstruction (n = 2), pulmonary embolism (n = 1), hypertensive urgency (n = 1), acute respiratory failure (n = 1), and ureteropelvic junction (UPJ) stricture (n = 1). No complications were attributable to pyeloperfusion. Three of 45 patients with biopsy-proven renal cell carcinoma experienced local recurrence resulting in local recurrence-free survival of 92% (95% confidence interval, 81.5%–100%) 3 years after ablation.ConclusionsRetrograde pyeloperfusion of the renal collecting system is a relatively safe and efficacious option for ureteral protection during renal tumor cryoablation. This adjunctive procedure should be considered for patients in whom cryoablation of a renal mass could potentially involve the ureter.     

A Pilot First-in-Human Study of Embrace,a Polyethylene Glycol-Based Liquid Embolic Agent,in the Embolization of Malignant and Benign Hypervascular Tumors

PurposeTo investigate the safety and efficacy of an aqueous polyethylene glycol-based liquid embolic agent, Embrace Hydrogel Embolic System (HES), in the treatment of benign and malignant hypervascular tumors.Materials and MethodsA prospective, single-arm, multicenter study included 8 patients, 5 males and 3 females, with a median age of 58.5 years (30–85 years), who underwent embolization in 8 tumors between October 2019 and May 2020. Technical success was defined as successful delivery of HES to the index vessel, with disappearance of >90% of the targeted vascular enhancement or, for portal vein embolization, occlusion of the portal branches to the liver segments for future resection. The volume of HES administered, ease of use (5 point Likert scale), administration time, and adverse events (AEs) were recorded. Evaluation was performed at 7, 30, and 90 days via clinical assessment and blood testing, and follow-up imaging was performed at 30 days.ResultsEight patients were enrolled, and 10 embolizations were performed in 8 lesions. Tumors included hepatocellular carcinoma (n = 4), renal angiomyolipoma (n = 3), and intrahepatic cholangiocarcinoma (n = 1). Technical success was 100%, and the average ease of use was 3.3 ± 1.0 SD. The HES delivery time was 1–28 minutes (median, 16.5 minutes), and the HES volume injected was 0.4–4.0 mL (median, 1.3 mL). All patients reached 30-day follow-up with imaging, and 6 patients reached 90-day follow-up. There were 3 serious AEs in 2 patients that were unrelated to the embolic agent.ConclusionHES resulted in a 100% embolization technical success rate. The product ease of use was acceptable, and no target vessel recanalization was noted on follow-up imaging at 30 days.     

A Single-Center 10-Year Retrospective Analysis of Cryoablation for the Management of Desmoid Tumors

PurposeTo determine the efficacy and safety of cryoablation in patients with desmoid tumors (DTs) retrospectively over a 10-year period at a single institution.Materials and MethodsBetween February 25, 2010, and February 25, 2020, 25 patients (age, 12–80 years) with 26 lesions (mean preprocedural tumor volume was 237 cm³) were treated over 44 cryoablation procedures. Eleven patients were treated with first-line therapy. Fourteen patients had previous medical therapy, radiotherapy, and/or surgery. Subsequent clinical follow-up, imaging outcomes, and safety were analyzed for technical success, change in total lesion volume (TLV) and viable tumor volume (VTV), modified response evaluation criteria in solid tumors (mRECIST), progression-free survival (PFS) for tumor progression and symptom recurrence, symptom improvement, and procedure-related complications. Symptomatic improvement was defined as documentation of relief of pain (partial or complete) and/or functional impairment.ResultsAll procedures were technically successful. At 7–12 months, median changes in TLV and VTV were −6.7% (P = .809) and −43.7% (P = .01), respectively. At 10–12 months, the mRECIST responses were complete response, 0%; partial response, 61.5% (8/13); stable disease, 30.8% (4/13); and progressive disease, 7.7% (1/13). The median PFS for tumor progression and symptom recurrence were not reached, with a median follow-up of 15.3 and 21.0 months, respectively. Symptomatic relief (partial or complete) was achieved in 96.9% (32/33) of patients. One major complication was noted (2.4%).ConclusionsIn this retrospectively identified cohort, cryoablation was effective and safe for the local control of extra-abdominal DTs in short-term follow-up.     

Comparison between Suprapapillary and Transpapillary Uncovered Self-Expandable Metallic Stent Placement for Perihilar Cholangiocarcinoma

PurposeTo compare the effectiveness, adverse events (AEs), stent patency, and patient survival with suprapapillary and transpapillary uncovered self-expandable metallic stent placement for perihilar cholangiocarcinoma.Materials and MethodsA single-center retrospective study of 54 patients with inoperable perihilar cholangiocarcinoma who underwent percutaneous transhepatic biliary stent placement between January 1, 2019, and August 31, 2021, was conducted. According to stent location, the patients were classified into 2 groups: suprapapillary (S) and transpapillary (T). Demographic data, Bismuth-Corlette classification, type and location of the stent, laboratory data, postprocedural AEs, procedural success, stent occlusion, reintervention rate, and mortality were compared between the groups.ResultsStent placement was suprapapillary in 13 (24.1%) patients and transpapillary in 41 (75.9%) patients. Mean age was higher in Group T (78 vs 70.5 years; P = .046). Stent occlusion rates were similar in the 2 groups (Group S, 23.8%; Group T, 19.5%), as were AE rates, the most common being cholangitis (Group S, 23.1%; Group T, 24.4%). There were no significant differences in revision rate (Group S, 7.7%; Group T, 12.2%) and 30-day mortality rate (Group S, 15.4%; Group T, 19.5%). Ninety-day mortality rate was statistically significantly higher in Group T (46.3% vs 15.4%; P = .046). Preprocedural bilirubin level was higher in Group T, as were postprocedural leukocyte and C-reactive protein (CRP) levels.ConclusionsSuprapapillary and transpapillary stent placement procedures were similar in terms of procedural success, occlusion rate, revision rate, postprocedural AEs, and 30-day mortality. Ninety-day mortality rate and postprocedural leukocyte and CRP levels were higher in Group T, although these patients were also older and had higher preprocedural bilirubin levels.     

Intermediate to Long-Term Clinical Outcomes of Percutaneous Cryoablation for Renal Masses

PurposeThe purpose of this study was to evaluate the effectiveness and adverse outcomes of percutaneous cryoablation (CA) for treatment of renal masses in a large cohort of patients.Materials and MethodsThis retrospective analysis included 299 CA procedures (297 masses in 277 patients) performed between July 2007 and May 2018 at a single institution. The mean patient age was 66.1 years (range, 30–93 years) with 65.8% being male. A total of 234 (78.8%) masses were biopsy-proven renal cell carcinoma (RCC). The mean maximal tumor diameter was 2.5 cm (range, 0.7–6.6 cm). Efficacy was assessed only for ablations of biopsy-proven RCC, whereas the evaluation of adverse events and renal function included all masses. Complications were graded according to the Society of International Radiology classification.ResultsMajor complications occurred in 3.0% of procedures (n = 9), none of which resulted in death or permanent disability. The mean imaging follow-up period was 27.4 months (range, 1–115) for the 199 RCC patients (204 ablated tumors) with follow-up imaging available. Complete response on initial follow-up imaging at mean 4.2 months (range, 0.3–75.6) was achieved in 195 of 204 tumors (95.6%) after a single session and in 200 of 204 tumors (98.0%) after 1 or 2 sessions. Of the RCC patients achieving complete response initially, local recurrence during the follow-up period occurred in 3 of 200 tumors (1.5%). Metastatic progression occurred in 10 of 193 (5.2%) RCC patients without prior metastatic disease during follow-up.ConclusionsCA for renal masses is safe and remains efficacious through intermediate- and long-term follow-up.     

Resolution of Pain after Percutaneous Image-Guided Cryoablation of Extraperitoneal Endometriosis

PurposeTo retrospectively evaluate the relief of pain after percutaneous image-guided cryoablation of symptomatic extraperitoneal endometriosis (EE).Material and MethodsFrom 2017 to 2022, cryoablation of EE was performed at a single institution on a total of 47 lesions in 42 consecutive patients (median age, 37 years; interquartile range [IQR], 33–39.5 years). Patient and procedural characteristics were reviewed retrospectively. Tolerance and outcomes in terms of pain and patient satisfaction were evaluated.ResultsThe median follow-up duration was 13.5 months (IQR, 1.1–37.7 months) after cryoablation. The median pain-free survival rate was 93.8% (95% confidence interval [CI], 77.3–98.4) at 6 months and 82.7% (95% CI, 58.8–93.5) after 12 months. Pain decreased from a median of 8/10 (IQR, 7–9) on the visual analog scale to 0/10 (IQR, 0–1) at the last follow-up (P < .0001). The median Patient Global Impression of Change score recorded at the last follow-up was 1/7 (IQR, 1–2). The efficacy rate of cryoablation to avoid secondary surgery was 92.8% (39/42) per patient and 93.6% (44/47) per nodule treated. Four patients (9.5%, 4/42) experienced an adverse event in the days following the procedure, and 1 patient (2%) experienced a severe adverse event.ConclusionsPercutaneous cryoablation is safe and effective in significantly reducing pain and obtaining local control of EE.     

Tumor and Ablation Margin Visibility during Cryoablation of Musculoskeletal Tumors: Comparing Intraprocedural PET/CT Images with CT-Only Images

PurposeTo compare tumor and ice-ball margin visibility on intraprocedural positron emission tomography (PET)/computed tomography (CT) and CT-only images and report technical success, local tumor progression, and adverse event rates for PET/CT-guided cryoablation procedures for musculoskeletal tumors.Materials and MethodsThis Health Insurance Portability and Accountability Act (HIPAA)–compliant and institutional review board–approved retrospective study evaluated 20 PET/CT-guided cryoablation procedures performed with palliative and/or curative intent to treat 15 musculoskeletal tumors in 15 patients from 2012 to 2021. Cryoablation was performed using general anesthesia and PET/CT guidance. Procedural images were reviewed to determine the following: (a) whether the tumor borders could be fully assessed on PET/CT or CT-only images; and (b) whether tumor ice-ball margins could be fully assessed on PET/CT or CT-only images. The ability to visualize tumor borders and ice-ball margins on PET/CT images was compared with that on CT-only images.ResultsTumor borders were fully assessable for 100% (20 of 20; 95% CI, 0.83–1) of procedures on PET/CT versus 20% (4 of 20; 95 CI, 0.057–0.44) of procedures on CT only (P < .001). The tumor ice-ball margin was fully assessable in 80% (16 of 20; 95% CI, 0.56–0.94) of procedures using PET/CT versus 5% (1 of 20; 95% CI, 0.0013–0.25) of procedures using CT only (P < .001). Primary technical success was achieved in 75% (15 of 20; 95% CI, 0.51–0.91) of procedures. There was local tumor progression in 23% (3/13; 95% CI, 0.050–0.54) of the treated tumors with at least 6 months of follow-up. There were 3 adverse events (1 Grade 3, 1 Grade 2, and 1 Grade 1).ConclusionsPET/CT-guided cryoablation of musculoskeletal tumors can provide superior intraprocedural visualization of the tumor and ice-ball margins compared with that provided by CT alone. Further studies are warranted to confirm the long-term efficacy and safety of this approach.     

Percutaneous Cryoablation: Safety and Efficacy for Pain Palliation of Metastases to Pleura and Chest Wall

PurposeTo assess safety and efficacy of percutaneous cryoablation for pain palliation of metastases to pleura and chest wall.Materials and MethodsThis retrospective single-center cohort study included 22 patients (27% female, mean age 63 y ± 11.4) who underwent 25 cryoablation procedures for pain palliation of 39 symptomatic metastases measuring 5.1 cm ± 1.9 (range, 2.0–8.0 cm) in pleura and chest wall between June 2012 and December 2017. Pain intensity was assessed using a numerical scale (0–10 points). Statistical tests t test, χ², and Wilcoxon signed rank were performed.ResultsPatients were followed for a median of 4.1 months (interquartile range [IQR], 2.3–10.1; range, 0.1–36.7 mo) before death or loss to follow-up. Following cryoablation, pain intensity decreased significantly by a median of 4.5 points (IQR, 2.8–6; range, 0–10 points; P = .0002 points, Wilcoxon signed rank). Pain relief of at least 3 points was documented following 18 of 20 procedures. Pain relief occurred within a median of 1 day following cryoablation (IQR, 1–2; range, 1–4 d) and lasted for a median of 5 weeks (IQR, 3–17; range, 1–34 wk). Systemic opioid requirements decreased in 11 of 22 patients (50%) by an average of 56% ± 34. Difference in morphine milligram equivalents was not significant (P = .73, Wilcoxon signed rank). No procedure-related complications occurred despite previous radiation of 7 tumors. Of 25 procedures, 22 (88%) were performed on an outpatient basis.ConclusionsPercutaneous cryoablation for metastases to pleura and chest wall can safely provide significant pain relief within days following a single session.     

Salvage Cryoablation for Local Recurrences of Thyroid Cancer Inseparable from the Trachea and Neurovascular Structures

PurposeTo demonstrate safety, feasibility, and effectiveness of cryoablation of recurrent papillary thyroid cancer ineligible for reoperation because of scarring, eligible for focal ablation as defined within 2015 American Thyroid Association guideline sections C16 and C17.Materials and MethodsWith multidisciplinary consensus, cryoablation was performed with curative intent for 15 tumors in 10 patients between January 2019 and July 2021. Demographics, procedural details, and serial postprocedural imaging findings were analyzed.ResultsThe mean age was 72.5 years (range, 57–88 years), and 80% of the patients were women. The tumors (mean size, 16 mm ± 6; range, 9–29 mm) received 1 session of cryoablation with 100% technical success. The mean and median postcryoablation tumor volumetric involution rates were 88% and 99%, respectively, with 9 (60%) of 15 tumors involuting completely or down to the scar and 6 (40%) involuting partially at the end of the study period. Tumor size did not increase after cryoablation (0% local progression rate). All tumors abutted the trachea, skin, and/or vascular structures, and hydrodissection failed in all cases because of scarring. The major adverse event rate was 20% (3/15), with 2 cases of voice change and 1 case of Horner syndrome; all resolved at 6 months with no permanent sequelae. No vascular, tracheal, dermal, or infectious adverse events occurred during a mean follow-up of 242 days (range, 114–627 days). One patient died at 386 days after cryoablation because of unrelated cholangiocarcinoma.ConclusionsCryoablation of local recurrences of papillary thyroid cancer abutting the trachea and/or neurovascular structures in the setting of hydrodissection failure because of scarring yielded a mean volumetric involution of 88%, primary efficacy of 60%, and objective response rate of 100% with no local recurrences or permanent complications during a mean follow-up of 242 days. The secondary efficacy and longer-term outcomes remain forthcoming.     

Endovascular Removal of Thrombus and Right Heart Masses Using the AngioVac System: Results of 234 Patients from the Prospective,Multicenter Registry of AngioVac Procedures in Detail (RAPID)

PurposeTo assess device and procedural safety and technical success associated with the use of the AngioVac System to remove vascular thrombi and cardiac masses.Materials and MethodsThe Registry of AngioVac Procedures in Detail (RAPID) study prospectively collected data for 234 patients receiving treatment with AngioVac at 21 sites between March 2016 and August 2019: 84 (35.9%) with caval thromboemboli (CTEs), 113 (48.3%) with right heart masses (RHMs), 20 (8.5%) with catheter-related thrombi (CRTs), and 4 (1.7%) with pulmonary emboli (PEs). Thirteen patients had a combination of procedures during the same admission.ResultsUsing the AngioVac system, 70%–100% thrombus or mass removal was achieved in 73.6% of patients with CTEs, 58.5% of patients with RHMs, 60% of patients with CRTs, and 57.1% of patients with PEs. Extracorporeal bypass time was < 1 hour for 176 (75.2%) procedures. Estimated blood loss was < 250 mL for 179 procedures (76.5%). Mean hemoglobin decreased from 10.4 g/dL ± 2.9 preoperatively to 9.4 g/dL ± 2.6 postoperatively. Transfusions were administered in 59 procedures (25.2%) with 47 transfusions (78.2%) being ≤ 2 U. There were 36 procedure-related complications, including 1 death.ConclusionsThe RAPID registry data demonstrate that the AngioVac System can be safely and effectively used to remove vascular thrombi and cardiac masses across a broad range of patient populations. The limited use of the device to remove pulmonary emboli in the present series precludes recommending the use of the AngioVac device for this indication.     

Percutaneous Cryoablation of Plasmacytomas: Oncologic Effectiveness and Adverse Events

PurposeTo evaluate the oncologic outcomes and adverse events associated with cryoablation of plasmacytomas.Materials and MethodsRetrospective review of an institutional percutaneous ablation database showed that 43 patients underwent 46 percutaneous cryoablation procedures for treatment of 44 plasmacytomas between May 2004 and March 2021. The treatment of 25 (25 of 44, 56.8%) tumors was augmented with bone consolidation/cementoplasty. The median patient age was 64 years (interquartile range [IQR], 54–69), and 30 of 43 (69.8%) patients were men. The median maximum plasmacytoma diameter was 5.0 cm (IQR, 3.1–7.0). Thirty of 44 (68.2%) tumors were periacetabular, vertebral, or located in the iliac wing. Twenty-nine of 44 (65.9%) cryoablated plasmacytomas were recurrent tumors after prior external beam radiation therapy (EBRT). Survival analyses were performed using the Kaplan-Meier method. Adverse events were graded using Society of Interventional Radiology criteria.ResultsThe 5-year estimated local tumor recurrence–free survival was 85.3% (95% CI, 74.1%–98.1%), the 5-year estimated new plasmacytoma–free survival was 49.9% (95% CI, 33.9%–73.4%), and the 5-year estimated overall survival was 70.4% (95% CI, 56.9%–87.1%). Nine of 46 (19.6%) major adverse events occurred in 8 patients, including 3 of 46 (6.5%) new or progressive pathologic fractures at the ablation site requiring surgical intervention, 3 of 46 (6.5%) nerve injuries, 1 of 46 (2.2%) avascular necrosis and femoral head collapse, 1 of 46 (2.2%) septic arthritis, and 1 of 46 (2.2%) acute renal failure caused by rhabdomyolysis.ConclusionsPercutaneous cryoablation is a viable treatment option for patients with plasmacytomas, including those with recurrent plasmacytomas after EBRT. Postcryoablation adverse events are relatively common.     

Robot-Assisted Transarterial Chemoembolization of Hepatocellular Carcinoma Using a Coaxial Microcatheter Driving Controller-Responder Robot System: Clinical Pilot Study

PurposeTo evaluate the feasibility and safety of robot-assisted transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) using a new coaxial microcatheter driving controller-responder robot (CRR) system.Materials and MethodsA single-center prospective pilot study approved by the institutional review board was conducted using this CRR developed after analyzing 20 cases of conventional TACE procedures from May to October 2021. The study included 10 patients with HCCs: 5 (median age, 72 years; range, 64–73 years) underwent robot-assisted TACE, and 5 (median age, 57 years; range, 44–76 years) underwent conventional TACE for comparison. The feasibility and safety of robot-assisted TACE were evaluated by assessing the technical success, procedure time, adverse event rate, radiation dose, and early tumor response.ResultsThe entire TACE procedure was divided into 30 steps, of which 8 could be robotized. In robot-assisted TACE, technical success was achieved in 4 (80%) of 5 patients. No procedure-related adverse event was observed. The median procedure time was 56 minutes. At the 1-month follow-up, 3 of the 4 patients showed a complete or partial response after robot-assisted TACE. The median radiation doses for the operator and patients were 0.4 and 2,167.5 μSv in robot-assisted TACE and 53.2 and 2,989.7 μSv in conventional TACE, respectively.ConclusionsRobot-assisted TACE using a new CRR system was feasible and safe for the treatment of HCC and could remarkably decrease radiation exposure for the operators.     

Risk Factors for Hemorrhagic Adverse Events in Percutaneous Transhepatic Biliary Drainage: A Prospective Multicenter Study

PurposeTo determine risk factors (RFs) for hemorrhagic adverse events (AEs) associated with percutaneous transhepatic biliary drainage (PTBD) and to develop a risk assessment model.Materials and MethodsThis was a multicenter, prospective, case control study between 2015 and 2020. Adults with an indication for PTBD were included. Patients who had undergone recent previous drainage procedures were excluded. Multiple variables were controlled. The exposure variables were the number of capsular punctures and passes (using the same puncture). A multivariate analysis was performed (logistic regression analysis).ResultsA total of 304 patients (mean age, 63 years ± 14 [range, 23–87 years]; female, 53.5%) were included. Hemorrhagic AEs occurred in 13.5% (n = 41) of the patients, and 3.0% (n = 9) of the cases were severe. Univariate analysis showed that the following variables were not associated with hemorrhagic AEs: age, sex, bilirubin and hemoglobin levels, type of pathology, portal hypertension, location of vascular punctures, ascites, nondilated bile duct, intrahepatic tumors, catheter features, blood pressure, antiplatelet drug use, and tract embolization. Multivariate analysis showed that number of punctures (odds ratio [OR], 2.5; P = .055), vascular punctures (OR, 4.1; P = .007), fatty liver or cirrhosis (OR, 3.7; P = .021), and intrahepatic tumor obstruction (Bismuth ≥ 2; OR, 2.4; P = .064) were associated with hemorrhagic AEs. Patients with corrected coagulopathies had fewer hemorrhagic AEs (OR, ?5.5; P = .026). The predictability was 88.2%. The area under the curve was 0.56 (95% confidence interval, 0.50–0.61).ConclusionsPreprocedural and intraprocedural RFs were identified in relation to hemorrhage with PTBD. AE risk assessment information may be valuable for prediction and management of hemorrhagic AEs.     

Cryoablation of Venous Malformations: A Systematic Review

This study aimed to review systematically the efficacy, safety, and technical aspects of cryoablation in the treatment of venous malformations (VMs) and to provide the groundwork for future studies. A literature search for clinical studies utilizing percutaneous cryoablation of VMs was performed. All clinical studies related to primary or secondary treatment of VMs with percutaneous cryoablation were included in this review. These selected studies were evaluated for patient characteristics, cryoablation technique, technical success, lesion size and pain scores before and after cryoablation, and adverse outcomes. Random effects analysis of postprocedural changes in lesion volume and pain scores was performed. There were 54 patients with 55 cases of cryoablation of VMs. Of these cases, 27 recorded changes in lesion volume and 31 recorded changes in pain scores. The weighted mean postprocedural decrease in lesion size was 92.0% (raw average, 71.7%). The weighted mean reduction in pain score was 77% (raw average, 78.2%). Considering all treated cases (55), complete resolution of symptoms was seen in 35 cases (63.6%) and overall (complete or partial) improvement in 52 cases (94.5%). Common postprocedural symptoms included pain, bruising, swelling and numbness lasting less than 2 weeks. There were two major adverse events (3.7%), with both cases due to persistent dysesthesia. Patients with a history of prior sclerotherapy demonstrated lower preprocedural and postprocedural pain scores (4.7 and 1.3) than patients without prior treatments (5.8 and 2.8). Cryoablation of VMs appears to be potentially safe and effective on limited short-interval follow-up.     

Safety and Efficacy of Percutaneous Cryoablation of Extraspinal Thyroid Cancer Bone Metastases with Curative Intent: Single-Center Experience with a Median Follow-up of More than 5 Years

PurposeTo determine the oncologic outcomes and safety profile of image-guided percutaneous cryoablation (PCA) for extraspinal thyroid cancer bone metastases with curative intent.Materials and MethodsBetween January 2010 and January 2020, 16 consecutive patients (8 men, 8 women; mean age, 61 years ± 19; range, 30–84 years) with 18 bone metastases (median bone tumor size, 19 mm; interquartile range [IQR], 12–29 mm; range, 7–58 mm) underwent PCA of oligometastatic extraspinal bone metastases. Thirteen (81%) patients were radioiodine therapy resistant. Two patients underwent 2 bone tumor ablations in a single session. Procedural data, oncologic outcomes, follow-up (with magnetic resonance imaging and positron emission tomography–computed tomography), and adverse events were retrospectively investigated. Local tumor progression-free survival, disease-free survival, and overall survival were estimated using the Kaplan-Meier method.ResultsA median of 2 cryoprobes (IQR, 1.25–3 cryoprobes; range, 1–7 cryoprobes) were used, with 2 freezing cycles; the median length of freezing was 20 minutes (IQR, 17–20 minutes; range, 10–20 minutes). The technical success was 100% (18/18), and the primary technical efficacy was 94.4% (17/18). The median follow-up was 68 months (IQR, 38–93 months). During follow-up, 3 of 17 (17.6%) tumors demonstrated local progression at 7, 13, and 27 months. Consequently, the 1-, 2-, 3-, 4-, and 5-year local tumor progression-free survivals were 93.3%, 84.6%, 76.9%, 75%, and 72.7%, respectively. Two of 16 (12.5%) patients died during follow-up at 43 and 88 months. The major adverse event rate was 5.5% (1/18) with 1 postablative acromion fracture.ConclusionsPCA for extraspinal thyroid cancer bone metastases demonstrated high local tumor control rates with a safe profile at long-term follow-up.     

External Validation of the Percutaneous Renal Ablation Complexity Scoring System in Patients Undergoing Percutaneous Cryoablation or Microwave Ablation of Renal Tumors

PurposeTo assess the ability of the Percutaneous Renal Ablation Complexity (P-RAC) scoring system to predict procedural complexity or adverse events (AEs) in adult patients undergoing percutaneous thermal ablation of renal tumors.Materials and MethodsA retrospective review of 240 consecutive adult patients who underwent percutaneous thermal renal ablation from 2004 to 2018 was conducted. The P-RAC score was calculated for each renal tumor and procedural complexity recorded. A correlation coefficient was calculated for the P-RAC score and both the number of probes used and procedural duration. Receiver operating characteristic curves assessed the score’s ability to predict the use of adjunctive techniques and/or major AEs, classified according to the Society of Interventional Radiology guidelines.ResultsFor the entire cohort, there was a weak correlation between P-RAC scores and both the number of probes used (r = 0.31; P < .001) and procedural duration (r = 0.18; P = .03). When evaluating only patients treated with microwave ablation (MWA), no correlation between P-RAC scores and either the number of probes (P = .7) used or procedural duration (P = .4) was found. The area under the curve (AUC) for the P-RAC score to predict the use of adjunctive techniques was 0.55 and 0.53 for the entire cohort and MWA group, respectively. The AUC for the P-RAC score to predict major AEs was 0.70, 0.71, and 0.73 for the entire cohort, MWA group, and cryoablation group, respectively.ConclusionsThe P-RAC scoring system is limited in its ability to predict percutaneous thermal renal tumor ablation procedural complexity, especially in patients treated with MWA. The scoring system may have a role in identifying patients at risk of major AEs.     

Experience with Compressed Gelfoam Plugs in Children during Liver Biopsies and Other IR Procedures: A Retrospective Single-Center Case Series

PurposeTo analyze the experience using compressed gelfoam plugs (CGPs) in children during liver biopsies and other interventional procedures.Materials and MethodsThis was a single-center, retrospective, consecutive case series of 477 various pediatric interventional radiology procedures using CGPs (January 2012 to December 2016) performed on 397 children (209 males, 188 females; median age, 7 years [range, 9 days–17.8 years]; median weight, 18 kg [range, 2.7–141 kg]). Of 477 procedures, most (n = 371) were liver biopsies, 98 were biopsies of other organs, and 8 were non-biopsy procedures. Analysis focused on liver biopsies.ResultsOf liver biopsies, a median of 2 CGPs were used per procedure, and the mean drop in hemoglobin was -0.36 g/dl (-3.0% change). Thirty-seven mild, 8 moderate, 2 severe, and 1 life-threatening (an anaphylaxis to CGP) adverse events (AEs) occurred. Analysis of liver biopsies with AEs showed significant association between number of passes, cores, and focal-type lesions (unadjusted logistic regression: P = .007, P = .022, P = .028, respectively) and age, weight, and number of passes (adjusted multiple logistic regression: P = .006, P = .032, P = .046, respectively). Technical problems relating to CGP deployment were noted in 5 (1%), without any AEs.ConclusionsCGPs were used in a wide variety of procedures and organs in children. There was 1 life-threatening AE resulting from the rare risk of anaphylaxis caused by the gelfoam-containing plug. After liver biopsies, transfusion was required in 2/371 (0.5%) procedures, 1 related to pre-biopsy anemia (0.25%).     

Partial Nephrectomy versus Percutaneous Cryoablation of Small Renal Cell Carcinomas: A Comparison of Adverse Events in a Prospective Multicenter Cohort Study

PurposeTo assess and compare complications and readmissions after partial nephrectomy and percutaneous cryoablation of cT1 renal cell carcinoma (RCC).Materials and MethodsPatients treated for cT1 RCC between 2019 and 2021 were prospectively and consecutively enrolled. Complications recorded within 30 and 90 days were graded according to the Clavien-Dindo classification, and percutaneous cryoablation was graded according to the Society of Interventional Radiology classification of adverse events. Major complications were defined as complications with a grade of ≥3 based on the Clavien-Dindo classification. Readmission within 30 days was recorded.ResultsThe cohort included 86 partial nephrectomies and 104 cryoablations. The complication rate within 90 days was 23% after partial nephrectomy and cryoablation (P = .98), with major complication rates of 3% after partial nephrectomy and 10% after cryoablation (P = .15). The readmission rates were 14% and 11% after partial nephrectomy and cryoablation, respectively (P = .48). Double-J stents were associated with overall complications (odds ratio [OR], 9.88; 95% confidence interval [CI], 2.18–44.68; P = .003) and readmissions (OR, 5.39; 95% CI, 1.37–21.06; P = .015) after cryoablation. A high versus low radius-endophytic-nearness-anterior-location score (OR, 5.86; 95% CI, 1.08–31.81; P = .040) and endophytic location (OR, 7.70; 95% CI, 1.72–34.50; P = .008) were associated with a higher complication rate after cryoablation. The Charlson Comorbidity Index (CCI) was associated with major complications after partial nephrectomy (OR, 2.12; 95% CI, 1.05–4.30; P = .036).ConclusionsPartial nephrectomy and cryoablation are comparable regarding complications within 90 days after treatment. Tumor complexity and double-J stents were associated with complications after cryoablation, and a high CCI was associated with complications after partial nephrectomy.