External validation of the ability of the mRENAL nephrometry score to identify patients at risk for major adverse events or local tumor recurrence after percutaneous renal cryoablation.

PURPOSE: The purpose of this study was to evaluate the ability of the mRENAL score to identify patients at risk of either major adverse events (AEs) and/or local tumor recurrence (LR) after percutaneous cryoablation (PCA) in an external patient population. METHODS: Patient demographic data were recorded. The RENAL and mRENAL nephrometry scores were calculated. Clinical outcomes such as AEs, LR, cancer-specific survival (CSS), and overall survival (OS) were collected. AEs were classified according to SIR criteria. Continuous variables and categorical variables were analyzed using the Wilcoxon rank sum test and chi-square test, respectively. Logistic regression analysis was performed to identify variables associated with major AEs or LR. RESULTS: The study included 207 patients (Males: n = 117 (56.5%)) with a mean age of 65.8 (± 11.2) years (range:27-90). Overall, the mean tumor diameter, RENAL score, and mean mRENAL score were 30.1 mm (± 11.4), 6.3 (± 1.7), and 6.8 (± 1.9), respectively. 14 patients (6.8%) and 13 patients (6.3%) experienced a major AE or LR after PCA, respectively. CSS and OS were 98.6% and 90.3%, respectively. For patients with major AEs after PCA, the mean tumor diameter (p < 0.0001), mean RENAL score (p = 0.03), and mean mRENAL score (p = 0.009) were all higher than those for patients without a major AE. Multi-variate regression analysis showed that only mean tumor diameter (p = 0.005) was predictive of a major AE. There were no statistically significant differences between patients with LR and patients without LR after PCA with regards to tumor size (p = 0.07), mean RENAL score (p = 0.32), or mean mRENAL score (p = 0.07). Multi-variate regression analysis showed that only mean tumor diameter (p = 0.01) was predictive of LR. CONCLUSION: The mRENAL score did not accurately identify patients at risk for either major AEs or LR. Maximum tumor diameter alone was predictive of both major AEs and LR, and should be the primary focus during patient selection.

Same-day discharge after percutaneous renal cryoablation and its effect on 30 day hospital re-admission rates and post-procedural complications.

PURPOSE: The purpose of this study is to identify if the local institutional shift from routine overnight observation to same-day discharge following percutaneous cryoablation (PCA) of renal tumors increases 30 day re-admission rates or serious adverse events (AEs). MATERIALS AND METHODS: This retrospective study included 133 adult patients. PCA patients in calendar years 2018-2019 were routinely observed overnight in the hospital, comprising the control group (Group A). PCA patients in calendar years 2021-2022 were routinely discharged the same day, comprising the test group (Group B). Relevant demographic information, tumor characteristics, technical outcomes, and clinical outcomes were recorded. RESULTS: 15 patients (11.3 %) from the total cohort were re-admitted to the hospital within 30 days of PCA for any reason. Seven patients (10.4 %) and eight patients (12.1 %) were re-admitted for any reason within 30 days in Group A and Group B, respectively, with no difference between the two groups (p = 0.76). Nine patients (6.8 %) from the total cohort were re-admitted to the hospital within 30 days for a diagnosis secondary to the procedure. Four patients (6 %) and five patients (7.6 %) were re-admitted within 30 days for reasons related to PCA in Group A and Group B, respectively, with no significant difference between the groups (p = 0.71). Eight patients (12 %) and four patients (6 %) had major AEs following PCA in Group A and Group B, respectively, with no difference between the two groups (p = 0.43). CONCLUSION: Overall, the change in post-procedural care after PCA did not have a deleterious effect on 30 day re-admission rates or rates of major AEs.

Percutaneous Ablation of T1b Renal Cell Carcinoma: An Overview.

PURPOSE OF REVIEW: There is increasing incidence of renal cell carcinoma (RCC) with multiple treatment options currently available. The purpose of this review is to outline patient selection and technical approaches and present the current literature for percutaneous ablation of T1b (4.1-7 cm) RCC. RECENT FINDINGS: An increasing number of retrospective studies and meta-analyses have evaluated the use of percutaneous ablation for T1b RCC. Overall, these studies tend to show that percutaneous ablation in this patient population is feasible. However, rates of major adverse events and local recurrence after percutaneous ablation for T1b RCC are both higher than when ablation is used for smaller tumors. As such, a multi-disciplinary, patient-centered approach is required. Due to the increasing literature in this area, the most recent National Comprehensive Cancer Network (NCCN) guidelines include percutaneous ablation as an option for non-surgical patients with T1b RCC.

NCCN Guidelines® Insights: Kidney Cancer, Version 2.2024.

The NCCN Guidelines for Kidney Cancer provide multidisciplinary recommendations for diagnostic workup, staging, and treatment of patients with renal cell carcinoma (RCC). These NCCN Guidelines Insights focus on the systemic therapy options for patients with advanced RCC and summarize the new clinical data evaluated by the NCCN panel for the recommended therapies in Version 2.2024 of the NCCN Guidelines for Kidney Cancer.

Safety and Technical Feasibility of Percutaneous Renal Cryoablation of Central Tumors without Pyeloperfusion.

PURPOSE: To assess the safety and technical success of percutaneous cryoablation (PCA) without pyeloperfusion in 94 patients with central renal tumors. MATERIALS AND METHODS: A retrospective review of all central renal tumors treated by PCA without pyeloperfusion was performed. Central tumors were defined as those involving the renal sinus fat on preprocedural cross-sectional imaging. Patient demographics and baseline tumor characteristics were recorded. The details of the PCA procedure, primary and secondary technical success, rates of local recurrence, adverse events (AEs), cancer-specific survival (CSS), and overall survival (OS) were compiled. RESULTS: Ninety-four patients (48 females [51%]; mean age, 68.2 years [range, 38-87 years]) with 94 central renal tumors were included. The mean maximal tumor diameter and mean RENAL nephrometry score were 37 mm (range, 15-67 mm) and 8 (range, 4-11), respectively. Primary technical success was achieved in 94% (n = 88) of procedures. Of the patients who did not achieve primary technical success, 3 underwent successful repeat PCA (secondary technical success, 97%; n = 91/94). The other 3 patients were surveilled for residual disease. Twenty-four patients (26%) required hydrodissection during PCA. Six patients (6%) experienced major AEs after PCA including hemorrhage requiring embolization (n = 3), hemorrhage requiring transfusions with admission (n = 2), and perinephric abscess necessitating drain placement (n = 1). Twenty-two patients (23%) experienced minor AEs. Nine patients (10%) experienced local recurrence during the follow-up period. OS was 94% (n = 88/94), whereas CSS was 98% (n = 92/94) during the study follow-up period (mean, 16 months [range, 1-102 months]). CONCLUSIONS: PCA of central renal tumors appears to be safe with high rates of technical success, even without the use of pyeloperfusion.

Percutaneous cryoablation of 100 anterior renal tumors: safety and technical success.

PURPOSE: To assess the safety, technical success, and clinical outcomes of percutaneous cryoablation (PCA) in patients with anterior renal tumors. METHODS: A retrospective analysis of patients with anterior renal tumors, defined as tumors at or anterior to the level of the renal pelvis, treated with CT-guided PCA from 2008 to 2022. Summary statistics included demographics and baseline tumor attributes. Treatment and follow-up metrics included primary and secondary technical success, adverse events (AEs) according to the SIR classification, local recurrence, overall survival (OS), and cancer-specific survival (CSS)). 100 patients (60 males; mean age: 63, mean BMI: 33, mean Charlson comorbidity index:6) with 100 anterior renal tumors were included. RESULTS: 78% of tumors were T1a and 22% T1b with mean maximal tumoral dimension of 29 mm (range: 6-62 mm) and mean distance to nearest critical structure 9 mm (range: 0-40 mm). Mean follow-up was 20.9 months (range: 3-103). 28% of PCAs required hydrodissection. Technical success was achieved in 92% of patients; with six remaining patients undergoing successful repeat PCA (secondary technical success: 98%). The remaining two patients without primary technical success were either surveilled or had a benign pathology on resulted concomitant biopsy. Four patients (4%) had major AEs (hemorrhage requiring prolonged admission, transfusion, or embolization (n = 3), perinephric abscess requiring drainage (n = 1)) and 27% had minor AEs. Eight patients (8%) had recurrence with a one-year OS of 94% and CSS of 100%. All recurrences underwent repeat ablation without additional recurrence and 3/8 (38%) were T1b and 5/8 (63%) were T1a tumors. CONCLUSION: PCA of anterior renal tumors can be performed safely with high rates of technical and oncologic success.

Short-term outcomes of uterine artery embolization for urgent or emergent abnormal uterine bleeding.

PURPOSE: To evaluate the outcomes of uterine artery embolization (UAE) for patients with urgent or emergent abnormal uterine bleeding (AUB). MATERIALS AND METHODS: Retrospective review of all patients from 1/2009-12/2020 who were treated urgently or emergently with UAE for AUB. Urgent and emergent cases were defined as those requiring inpatient admissions. Demographic data were collected for each patient including hospitalizations related to bleeding and length of stay (LOS) for each hospitalization. Hemostatic interventions other than UAE were collected. Hematologic data were collected before and after UAE including hemoglobin, hematocrit, and transfusion products. Data specific to the UAE procedure included complication rates, 30-day readmission, 30-day mortality, embolic agent, site of embolization, radiation dose, and procedure time. RESULTS: 52 patients (median age: 39) underwent 54 urgent or emergent UAE procedures. The most common indications for UAE were malignancy (28.8%), post-partum hemorrhage (21.2%), fibroids (15.4%), vascular anomalies (15.4%), and post-operative bleeding (9.6%). There were no procedure-related complications. Following UAE, 44 patients (84.6%) achieved clinical success and required no additional intervention. Packed red blood cell transfusion decreased from a mean of 5.7 to 1.7 units (p < 0.0001). Fresh frozen plasma transfusion decreased from a mean of 1.8 to 0.48 units (p = 0.012). 50% of patients received a transfusion prior to UAE, while only 15.4% were transfused post-procedure (p = 0.0001). CONCLUSIONS: Emergent or urgent UAE is a safe and effective procedure to control AUB hemorrhage secondary to a variety of etiologies.

Limited ability of the renal ablation-specific (MC)2 risk scoring system to predict major adverse events from percutaneous renal microwave ablation.

PURPOSE: To access if the (MC)2 scoring system can identify patients at risk for major adverse events following percutaneous microwave ablation of renal tumors. METHODS: Retrospective review of all adult patients who underwent percutaneous renal microwave ablation at two centers. Patient demographics, medical histories, laboratory work, technical details of the procedure, tumor characteristics, and clinical outcomes were collected. The (MC)2 score was calculated for each patient. Patients were assigned to low-risk (<5), moderate-risk (5-8) and high-risk (>8) groups. Adverse events were graded according to the criteria from the Society of Interventional Radiology guidelines. RESULTS: A total of 116 patients (mean age = 67.8 [95%CI 65.5-69.9], 66 men) were included. 10 (8.6%) and 22 (19.0%) experienced major or minor adverse events, respectively. The mean (MC)2 score for patients with major adverse events (4.6 [95%CI 3.3-5.8]) was not higher than those with either minor adverse events (4.1 [95%CI 3.4-4.8], p = 0.49) or no adverse events (3.7 [95%CI 3.4-4.1], p = 0.25). However, mean tumor size was greater in those with major adverse events (3.1 cm [95%CI 2.0-4.1]) than minor adverse events (2.0 cm [95%CI 1.8-2.3], p = 0.01). Patients with central tumors were also more likely to experience major adverse events compared to those without central tumors (p = 0.02). The area under the receiver operator curve to predict major adverse events was 0.61 (p = 0.15), indicating a poor ability of the (MC)2 score to predict major adverse events. CONCLUSION: The (MC)2 risk scoring system does not accurately identify patients at risk for major adverse events from percutaneous microwave ablation of renal tumors. The mean tumor size and central tumor location may serve as a better indicator for risk assessment of major adverse events.

Transarterial embolization of T1b and T2a renal cell carcinoma prior to percutaneous cryoablation: a retrospective comparative study.

PURPOSE: To compare outcomes in patients with T1b and T2a renal cell carcinoma (RCC) treated with percutaneous cryoablation (PCA) who underwent transarterial embolization (TAE) of the RCC prior to PCA (TAE + PCA) to patients who were treated with PCA alone. METHODS: Retrospective review of all adult patients with T1b (4.1-7 cm) and T2a (7.1-10 cm) RCC treated with PCA from 2008 to 2021. Data collected included age, sex, tumor diameter, RENAL nephrometry score, technical success, adverse events (AEs), changes in serum creatinine, local control, and recurrence rates. A p value of 0.05 was considered the threshold for statistical significance. RESULTS: 13 patients with 13 RCCs (mean age: 72.7 ± 10.4; 54% male) and 35 patients with 37 RCCs (mean age: 66.7 ± 10.6; 60% male) were included in the TAE + PCA and PCA groups, respectively. The TAE + PCA group had larger mean tumor diameter (5.7 ± 1.1 cm vs. 4.7 ± 0.6 cm; p < 0.0001) and higher mean RENAL nephrometry score (8.9 ± 1.1 vs. 7.8 ± 1.5; p = 0.02). There were no differences between the groups with respect to technical success of PCA (p = 0.46), local tumor control (p = 0.3), or mean number of procedures to achieve local tumor control (p = 0.85). Mean increase in serum creatinine was not significantly different between the two groups (p = .63). Major AEs were similar between the groups (p = 1); however, the TAE + PCA group had no major hemorrhagic AEs while the PCA alone group had three (8.3%). CONCLUSION: TAE + PCA in patients with T1b or T2 RCC is technically feasible without significant added detriment to renal function. This combined approach may help to reduce hemorrhagic AEs but larger patient cohorts are needed.

Rectal Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

This selection from the NCCN Guidelines for Rectal Cancer focuses on management of malignant polyps and resectable nonmetastatic rectal cancer because important updates have been made to these guidelines. These recent updates include redrawing the algorithms for stage II and III disease to reflect new data supporting the increasingly prominent role of total neoadjuvant therapy, expanded recommendations for short-course radiation therapy techniques, and new recommendations for a "watch-and-wait" nonoperative management technique for patients with cancer that shows a complete response to neoadjuvant therapy. The complete version of the NCCN Guidelines for Rectal Cancer, available online at NCCN.org, covers additional topics including risk assessment, pathology and staging, management of metastatic disease, posttreatment surveillance, treatment of recurrent disease, and survivorship.

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

PURPOSE: To 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 METHODS: A 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. RESULTS: For 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. CONCLUSIONS: The 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.

Safety and Effectiveness of Transhepatic Access for Percutaneous Renal Mass Cryoablation: A Multicenter Cohort.

PURPOSE: To establish transhepatic percutaneous cryoablation of renal masses as a safe and effective approach. MATERIALS AND METHODS: A retrospective review of records from 3 separate medical centers was performed identifying 23 patients (median age, 63 years [range 41-84 years]; 12 female [52.2%]) who underwent percutaneous transhepatic cryoablation for right-sided renal masses (median diameter, 2.4 cm [1.5-4.6 cm]) between 2008 and 2021. The median radius, exophytic/endophytic, nearness to collecting system or sinus, anterior/posterior, and location relative to polar lines (RENAL) nephrometry score was 5 (4-10). Adverse events (AEs) were classified according to the Society of Interventional Radiology (SIR) and Clavien-Dindo (CD) classifications. Primary and secondary technical success of each procedure were recorded. RESULTS: Renal cell carcinoma (of any subtype) was found in 10 (71.5%) of the 14 masses that were biopsied. Tract cautery was used for transhepatic probes in 14 (63.6%) of 22 procedures. Three (13%) of 23 patients had postprocedural AEs. Two cases (8.6%) were hemorrhages related to transhepatic access (SIR moderate-2, CD 2; SIR severe-3, CD 1), and 1 case (4.4%) was related to bowel injury (SIR severe-3, CD 3a). There were no instances of pneumothorax. Tract cautery was used in the procedures that resulted in an AE. Primary technical success was achieved in 84.2% (16/19) of procedures, whereas secondary technical success was achieved in 2 additional patients. The secondary technical success rate was 94.7% (18/19). Four patients did not have imaging follow-up. CONCLUSIONS: The transhepatic approach to cryoablation of renal masses appears to have an acceptable safety profile and technical success rate. Larger studies, preferably comparative to nontranshepatic approach, are recommended.

Research Priorities in Percutaneous Image- and Endoscopy-Guided Interventions for Biliary and Gallbladder Diseases: Proceedings from the Society of Interventional Radiology Foundation Multidisciplinary Research Consensus Panel.

Recent technological advancements, including the introduction of disposable endoscopes, have enhanced the role of interventional radiology (IR) in the management of biliary and gallbladder diseases. There are unanswered questions in this growing field. The Society of Interventional Radiology Foundation convened a virtual research consensus panel consisting of a multidisciplinary group of experts to develop a prioritized research agenda regarding percutaneous image- and endoscopy-guided procedures for biliary and gallbladder diseases. The panelists discussed current data, opportunities for IR, and future efforts to maximize IR's ability and scope. A recurring theme throughout the discussions was to find ways to reduce the total duration of percutaneous drains and improve patients' quality of life. After the presentations and discussions, research priorities were ranked on the basis of their clinical relevance and impact. The research ideas ranked top 3 were as follows: (a) percutaneous multimodality management of benign anastomotic biliary strictures (laser vs endobiliary ablation vs cholangioplasty vs drain upsize protocol alone), (b) ablation of intraductal cholangiocarcinoma with and without stent placement, and (c) cholecystoscopy/choledochoscopy and lithotripsy in nonsurgical patients with calculous cholecystitis. Collaborative, retrospective, and prospective research studies are essential to answer these questions and improve the management protocols for patients with biliary and gallbladder diseases.

Intercostal Cryoneurolysis.

Chest wall pain affects many patients following chest surgery, fractures, or malignancies, and can be very difficult to manage with normal pharmacologic agents. Intercostal ablation provides one alternative treatment modality for patients suffering from intercostal pain. Intercostal cryoneurolysis involves using extreme cold to cause Wallerian degeneration of the targeted intercostal nerve. This article reviews the patient selection, technique, and complications in the utilization of intercostal neurolysis in the treatment of intractable chest pain.

Trans-arterial embolization of renal cell carcinoma: a systematic review and meta-analysis.

PURPOSE: To evaluate if trans-arterial embolization (TAE) of the primary tumor in patients with renal cell carcinoma (RCC) improves symptomatology such as pain and hematuria or oncologic outcomes such as progression-free survival (PFS) and overall survival (OS). MATERIALS AND METHODS: The systematic review search included PubMed, Ovid/MEDLINE, and Embase for full-text English articles including randomized and non-randomized prospective trials as well as prospective and retrospective case series. To be included, prospective trials needed ≥ 25 patients in each arm while case series and retrospective chart reviews required at least two patients. Evaluated outcomes included PFS, OS, change in tumor size, improvements in pain, improvements in hematuria, and adverse events (AEs). RESULTS: 1327 articles were retrieved and screened. Nine studies met inclusion criteria (retrospective case series, n = 8; non-randomized prospective trial, n = 1) which included 237 patients (M = 156 (65.8%); F = 56 (23.6%); gender unreported = 25 (10.5%); mean age: 69.4 (range: 38-87)) with a mean tumor diameter of 9.3 cm (5.2-10.5). When reported, the TNM stages were stage I (n = 10), II (n = 18), III (n = 36), and IV (n = 121). 60 patients were treated for pain and hematuria. After TAE, pain improved in 59 patients (98.3%) and hematuria improved in 57 patients (95%). A meta-analysis for improvements in pain and hematuria demonstrated an event rate of pain improvement of 0.952 (0.788-0.990; p < 0.001) and an event rate for hematuria improvement of 0.923 (0.809-0.971; p < 0.001). Median OS ranged from 1 to 39 months but only one study reported PFS (10.5 months). Only one study demonstrated a statistically significant improvement in OS with TAE when compared with patients that did not undergo TAE (p = 0.02). A reduction in tumor size was only achieved in 17 patients (17/49; 34.7%) limiting evaluation. AEs included fever (n = 115/237; 48.5%), flank pain (n = 72/237; 30.4%), nausea (n = 58/237; 24.5%), hematuria (n = 12/237; 5.1%), hypertension (n = 12/237; 5.1%), reduced GFR (n = 6/237; 2.5%), hematoma (n = 6/237,2.5%), and ileus (n = 3/237; 1.3%). CONCLUSION: TAE monotherapy of the primary tumor in patients with RCC improves symptomatology such as pain and hematuria with an acceptable safety profile.

Utility of the RENAL Nephrometry Scoring System in Predicting Adverse Events and Outcomes of Percutaneous Microwave Ablation of Renal Tumors.

PURPOSE: To assess the utility of the radius, exophytic/endophytic, nearness to collecting system or sinus, anterior/posterior, and location relative to polar lines (RENAL) nephrometry scoring system at predicting adverse events and outcomes in percutaneous microwave ablation (MWA) of renal tumors. MATERIALS AND METHODS: A retrospective review of 116 patients who underwent MWA from 2004 to 2018 at 2 large university hospitals was conducted. Patient demographics and tumor characteristics were collected. The RENAL nephrometry scores were calculated, and procedure-related adverse events were stratified into minor and major (the Society of Interventional Radiology classification of class C or higher). Technical and oncologic outcomes were based on follow-up magnetic resonance imaging and computed tomography scans after ablation. RESULTS: The mean RENAL score was 6.6 (range, 4-11), and the mean tumor size was 24 mm. Follow-up ranged between 16 and 161 weeks (median, 50 weeks; mean, 65 weeks). Oncologic control was achieved in 96% (n = 111) of patients. The major and minor adverse event rates were 8.6% (n = 10) and 17% (n = 19), respectively. The mean RENAL score for patients with recurrent and/or residual tumor (8.2 ± 2.7) was higher than that for patients without disease recurrence (6.5 ± 3.5, P = .05). However, in a multivariate analysis, the RENAL score was not found to be an independent predictor of oncologic outcomes (odds ratio, 1.548; P = .092). CONCLUSIONS: The RENAL nephrometry score has minimal utility for predicting outcomes and adverse events in MWA of renal tumors. The inconsistent nature of RENAL nephrometry scoring in percutaneous ablation procedures underscores the need for an ablation-specific risk stratification system.

External Validation of the Renal Ablation-Specific (MC)2 Risk Scoring System in Predicting Complications from Percutaneous Renal Cryoablation.

PURPOSE: The (MC)2 score is a renal ablation-specific risk scoring system to predict major complications from percutaneous renal cryoablation (PRCA). However, it is untested in an external population of patients. The purpose of this study is to validate the ability of the (MC)2 score to predict major complications after PRCA in an external population. MATERIALS AND METHODS: Retrospective review of patients who underwent PRCA from 2004 to 2019. Patient demographics, medical histories, and tumor characteristics were collected. The (MC)2 score was calculated and patients were assigned to low risk (< 5), moderate risk (5-8) and high-risk (> 8) groups. Complications were recorded. Major complications were classified according to CIRSE guidelines. RESULTS: Two hundred and one patients [M = 116; F = 85; median age = 65 (range 27-90)] met inclusion criteria. Eleven patients (5.5%) developed major complications and 50 patients (24.9%) developed minor complications. Of patients with major complications, mean tumor diameter was 39 mm (± 10.4), seven patients (63.6%) had a central tumor, four patients (36.4%) had complicated diabetes, and one patient (9.1%) had a prior MI. Major complication rates were 2.1%, 14%, and 14.3% in the (MC)2 low risk, moderate risk, and high risk groups, respectively. The mean (MC)2 score for patients with major complications [6.2 (± 2.4)] was higher than the mean score for patients with minor complications [4.7 (± 2.4) (p = 0.07)] and no complications [3.9 (± 1.9) (p < 0.01)]. The area under the ROC curve to predict major complications was 0.78. CONCLUSION: The (MC)2 risk scoring system appropriately identifies patients at risk for major complications from PRCA in this external patient population.

Role of Imaging in Renal Cell Carcinoma: A Multidisciplinary Perspective.

With the expansion in cross-sectional imaging over the past few decades, there has been an increase in the number of incidentally detected renal masses and an increase in the incidence of renal cell carcinomas (RCCs). The complete characterization of an indeterminate renal mass on CT or MR images is challenging, and the authors provide a critical review of the best imaging methods and essential, important, and optional reporting elements used to describe the indeterminate renal mass. While surgical staging remains the standard of care for RCC, the role of renal mass CT or MRI in staging RCC is reviewed, specifically with reference to areas that may be overlooked at imaging such as detection of invasion through the renal capsule or perirenal (Gerota) fascia. Treatment options for localized RCC are expanding, and a multidisciplinary group of experts presents an overview of the role of advanced medical imaging in surgery, percutaneous ablation, transarterial embolization, active surveillance, and stereotactic body radiation therapy. Finally, the arsenal of treatments for advanced renal cancer continues to grow to improve response to therapy while limiting treatment side effects. Imaging findings are important in deciding the best treatment options and to monitor response to therapy. However, evaluating response has increased in complexity. The unique imaging findings associated with antiangiogenic targeted therapy and immunotherapy are discussed. An invited commentary by Remer is available online. Online supplemental material is available for this article. ©RSNA, 2021.

ACR Appropriateness Criteria® Nontraumatic Aortic Disease.

Nontraumatic aortic disease can be caused by a wide variety of disorders including congenital, inflammatory, infectious, metabolic, neoplastic, and degenerative processes. Imaging examinations such as radiography, ultrasound, echocardiography, catheter-based angiography, CT, MRI, and nuclear medicine examinations are essential for diagnosis, treatment planning, and assessment of therapeutic response. Depending upon the clinical scenario, each of these modalities has strengths and weaknesses. Whenever possible, the selection of a diagnostic imaging examination should be based upon the best available evidence. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment. The purpose of this document is to assist physicians select the most appropriate diagnostic imaging examination for nontraumatic aortic diseases.