Patient Access of Their Radiology Reports Before and After Implementation of 21st Century Cures Act Information-Blocking Provisions at a Large Multicampus Health System.

BACKGROUND. To implement provisions of the 21st Century Cures Act that address information blocking, federal regulations mandated that health systems provide patients with immediate access to elements of their electronic health information, including imaging results. OBJECTIVE. The purpose of this study was to compare patient access of radiology reports before and after implementation of the information-blocking provisions of the 21st Century Cures Act. METHODS. This retrospective study included patients who underwent outpatient imaging examinations from January 1, 2021, through December 31, 2022, at three campuses within a large health system. The system implemented policies to comply with the Cures Act information-blocking provisions on January 1, 2022. Imaging results were released in patient portals after a 36-hour embargo period before implementation versus being released immediately after report finalization after implementation. Data regarding patient report access in the portal and report acknowledgment by the ordering provider in the EMR were extracted and compared between periods. RESULTS. The study included reports for 1,188,692 examinations in 388,921 patients (mean age, 58.5 ± 16.6 [SD] years; 209,589 women, 179,290 men, eight nonbinary individuals, and 34 individuals for whom sex information was missing). A total of 77.5% of reports were accessed by the patient before implementation versus 80.4% after implementation. The median time from report finalization to report release in the patient portal was 36.0 hours before implementation versus 0.4 hours after implementation. The median time from report release to first patient access of the report in the portal was 8.7 hours before implementation versus 3.0 hours after implementation. The median time from report finalization to first patient access was 45.0 hours before implementation versus 5.5 hours after implementation. Before implementation, a total of 18.5% of reports were first accessed by the patient before being accessed by the ordering provider versus 44.0% after implementation. After implementation, the median time from report release to first patient access was 1.8 hours for patients with age younger than 60 years old versus 4.3 hours for patients 60 years old or older. CONCLUSION. After implementation of institutional policies to comply with 21st Century Cures Act information-blocking provisions, the length of time until patients accessed imaging results decreased, and the proportion of patients who accessed their reports before the ordering provider increased. CLINICAL IMPACT. Radiologists should consider mechanisms to ensure timely and appropriate communication of important findings to ordering providers.

Update on Percutaneous Ablation for Sarcoma.

PURPOSE OF REVIEW: To provide an update on the current state of percutaneous thermal ablation in the treatment of sarcoma. RECENT FINDINGS: Data continue to accrue in support of ablation for local control and palliation of specific sarcoma subtypes such as extra-abdominal desmoid fibromatosis and for broader indications such as the treatment of oligometastatic disease. The synergistic possibilities of various combination therapies such as cryoablation and immunotherapy represent intriguing areas of active investigation. Histotripsy is an emerging non-invasive, non-thermal ablative modality that may further expand the therapeutic arsenal for sarcoma treatment. Percutaneous thermal ablation is a valuable tool in the multidisciplinary management of sarcoma, offering a minimally invasive adjunct to surgery and radiation therapy. Although there remains a paucity of high-level evidence specific to sarcomas, ablation techniques are demonstrably safe and effective for achieving local tumor control and providing pain relief in select patients and are of particular benefit in those with metastatic disease or requiring palliative care.

Percutaneous Cryoablation of Plasmacytomas: Oncologic Effectiveness and Adverse Events.

PURPOSE: To evaluate the oncologic outcomes and adverse events associated with cryoablation of plasmacytomas. MATERIALS AND METHODS: Retrospective 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. RESULTS: The 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. CONCLUSIONS: Percutaneous cryoablation is a viable treatment option for patients with plasmacytomas, including those with recurrent plasmacytomas after EBRT. Postcryoablation adverse events are relatively common.

Radiofrequency Ablation of Benign and Malignant Thyroid Nodules.

Thyroid nodule treatment has significantly evolved over recent years with attempts to individualize treatment on the basis of the cause of the nodule and patient performance status. The risks and complications associated with surgery and radioactive iodine have promoted interest in additional therapies such as radiofrequency ablation (RFA). RFA creates an electrical current through a target tissue (thyroid nodule) with resultant tissue heating causing coagulative necrosis. National and international groups are beginning to recognize the role of RFA as a viable therapeutic option in the treatment of thyroid nodules. Based on numerous guidelines, RFA is indicated in the treatment of symptomatic benign nodules and autonomously functioning nodules when surgery is refused or when the patient would not tolerate surgery. The treatment of thyroid malignancy with RFA is controversial, with some groups advocating for its use in the treatment of small papillary thyroid cancers in specific scenarios. The most important aspect of RFA is the preprocedural workup and adequate patient selection. Procedural technique varies among centers. However, RFA is typically performed as a single-day-admission outpatient procedure. Methods such as hydrodissection and a moving shot technique are employed to ensure adequate coverage of the nodule without overtreating the peripheries and damaging sensitive structures. As a result, the procedure is well tolerated, and major complications such as recurrent laryngeal nerve injury and nodule rupture are very rare. In the proper patient cohort, thyroid RFA offers an efficacious and safe option in the management of thyroid nodules. An invited commentary by Filippiadis and Vrachliotis is available online. ©RSNA, 2022.

Prevention of Allergic-like Reactions at Repeat CT: Steroid Pretreatment versus Contrast Material Substitution.

Background It is unclear whether steroid premedication is an effective means of preventing repeat allergic-like reactions in high-risk patients with a previous allergic-like reaction to iodinated contrast material (ICM). Purpose To compare the effectiveness of ICM substitution (ie, using iohexol in a patient with a previous iopromide reaction) with 12- and 2-hour steroid premedication for preventing repeat acute allergic-like reactions in high-risk patients. Materials and Methods This retrospective study identified all high-risk (ie, having a previous allergic-like reaction) adult and pediatric patients who underwent a contrast-enhanced CT examination at the institution from June 1, 2009, to May 9, 2017. Prophylactic treatments and repeat reactions were identified using chart review. The effectiveness of prophylactic treatments on repeat reaction rates was examined with multivariable regression models that used generalized estimating equations. Results A total of 1973 high-risk patients who underwent 4360 subsequent ICM-enhanced CT examinations were included. Of the 4360 examinations, a total of 280 allergic-like reactions occurred (6%) in 224 of the 1973 patients (11% of patients), with only 19 of 280 reactions (7%) that were more severe than the previous reaction being demonstrated. After adjustment, patients who received a different ICM with and without steroid premedication had a significantly lower rate of repeat reactions than did patients who received steroid premedication and the same ICM (same ICM and steroid premedication: 80 of 423 examinations [19%]; different ICM and no steroid premedication: 10 of 322 examinations [3%]; odds ratio [OR], 0.14 [95% CI: 0.06, 0.33]; P < .001; different ICM and steroid premedication: five of 166 patients [3%]; OR, 0.12 [95% CI: 0.04, 0.36]; P < .001). When examining the first scan only, patients who received the same ICM had a similar risk of repeat reactions regardless of whether they received steroid premedication (steroid premedication: 44 of 172 patients [26%] vs no premedication: 73 of 298 patients [25%]; OR, 1.00 [95% CI: 0.64, 1.57]; P = .99). Conclusion In this cohort, using an iodinated contrast material (ICM) substitution was more effective for preventing repeat allergic-like reactions than using steroid premedication and the same ICM that caused the previous reaction. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Davenport and Weinstein in this issue.

Image-guided tumor ablation in gynecologic oncology: Review of interventional oncology techniques and case examples highlighting a collaborative, multidisciplinary program.

As interventional oncology services within radiology mature, image-guided ablation techniques are increasingly applied to recurrent gynecologic malignancies. Ablation may be performed using thermal techniques like cryoablation, microwave ablation, or radiofrequency ablation, as well as non-thermal ones, such as focused ultrasound or irreversible electroporation. Feasibility and approach depend on tumor type, size, number, anatomic location, proximity of critical structures, and goals of therapy. Current indications include local control of limited metastatic disease or palliation of painful bone metastases refractory or unsuitable to conventional therapies. Technical aspects of these procedures, including methods to protect nearby critical structures are presented through illustrative examples. Cases amenable to image-guided ablation include, but are not limited to, hepatic or pulmonary metastases, musculoskeletal metastases, retroperitoneal nodal metastases, pelvic side wall disease, abdominal wall disease, and vaginal or vulvar tumors. Protective maneuvers, such as hydro-displacement of bowel, neuromonitoring, and retrograde pyeloperfusion through ureteral stents, permit safe ablation despite close proximity to vulnerable nerves or organs. Image-guided ablation offers an alternative modality to achieve local tumor control without the risks associated with surgery or systemic treatment in appropriately selected patients. A multidisciplinary approach to use of image-guided ablation includes collaboration between gynecologic oncology, interventional radiology, anesthesia, urology and radiation oncology teams allowing for appropriate patient-centered case selection. Long-term follow up and additional studies are needed to determine the oncologic benefits of such techniques.

Percutaneous Image-Guided Core Needle Biopsy of Neuroendocrine Tumors: How Common Is Intraprocedural Carcinoid Crisis?

PURPOSE: To retrospectively evaluate the incidence of carcinoid crisis, other complications, and physiologic disturbances during percutaneous image-guided core needle biopsy of neuroendocrine tumors (NETs) in the lung and the liver. MATERIALS AND METHODS: Between January 2010 and January 2020, 106 computed tomography (CT) or ultrasound (US)-guided core needle biopsies of lung and liver NETs were performed in 95 consecutive adult patients. The mean age was 64 ± 13 years, and 48% were female. The small bowel was the most common primary site (33%, 31/95), and 32 (34%) patients had pre-existing symptoms of carcinoid syndrome. The mean tumor size was 3.2 ± 2.6 cm, and mean number of passes was 3.4 ± 1.6. A 17/18-gauge needle was used in 91% (96/106) of the biopsies. Thirteen (12%) patients received either outpatient or prophylactic octreotide. RESULTS: No patients experienced carcinoid crisis or needed octreotide, inotropes, vasopressors, or resuscitation. A single biopsy procedure (0.9%, 1/106) was complicated by bleeding that required angiographic hepatic artery embolization. Changes in pre-biopsy- versus post-biopsy systolic blood pressure and heart rate were -1.6 mm Hg (P = .390) and 0.6 beat/min (P = .431), respectively. Tumor functional status, overall tumor burden, and the elevation of neuroendocrine markers were not associated with intraprocedural physiologic disturbances. There were 4 minor complications (0.4%, 4/106) associated with the biopsy procedure that were not attributed to hormone excretion from tumor manipulation. CONCLUSIONS: Percutaneous image-guided core biopsy of NETs is safe, with low complication rate and no definite carcinoid crisis in the current cohort.

A Single-Institution Experience in Percutaneous Image-Guided Cryoablation of Lymph Node Metastases.

OBJECTIVE. The purpose of this study was to assess the feasibility, safety, and efficacy of percutaneous cryoablation for the treatment of lymph node metastases. MATERIALS AND METHODS. In this single-institution retrospective study 55 patients were identified who underwent CT-guided cryoablation of metastatic lymph nodes between November 2006 and September 2019. Patient demographics, disease characteristics, and procedural details were recorded. The primary endpoints were technical success and major complications. The secondary endpoints were time to local and time to distant progression. Complications were graded according to the Society of Interventional Radiology consensus guidelines. RESULTS. The study sample comprised 55 patients (42 men, 13 women; mean age 64 ± 12 years) who underwent 61 cryoablation procedures to treat 65 lymph node metastases. Targeted nodes measured 1.7 ± 1.2 cm in mean short-axis diameter. Technical success was achieved in 60 of 61 cryoablation procedures (98%). Adjunctive maneuvers performed to protect adjacent structures included hydrodissection (n = 40), ureteral stenting (n = 3), and neural monitoring (n = 3). There were two Society of Interventional Radiology major complications (3%): pneumothorax (n = 1) and bleeding (n = 1). Local tumor control was achieved in treatment of 53 of 65 (82%) nodal metastases within a median of 25 months (range, 1-121 months) of follow-up. Local progression occurred in 12 of 65 cases (18%); the median time to recurrence was 11 months. CONCLUSION. Percutaneous cryoablation of nodal metastases is feasible and safe. Further investigation is warranted to assess the long-term efficacy of this technique and to define its role in oncologic care.

Acute Reactions to Gadolinium-Based Contrast Agents in a Pediatric Cohort: A Retrospective Study of 16,237 Injections.

BACKGROUND. Incidences and risk factors for acute reactions to gadolinium-based contrast agents (GBCAs) are not fully understood, particularly in pediatric patients. OBJECTIVE. The purpose of this study was to retrospectively examine allergiclike and physiologic acute reactions in pediatric patients who receive GBCAs for MRI examinations. METHODS. The study cohort consisted of all pediatric patients (age < 18 years old) who underwent an MRI examination with a GBCA at our institution from June 1, 2009, to May 9, 2017. Acute reactions were identified by medical record review and classified by severity using the American College of Radiology guidelines. Potential risk factors for reactions were examined using generalized estimating equation methods accounting for rare events. RESULTS. A total of 16,237 GBCA injections (10,141 gadodiamide injections, 4880 gadobutrol injections, and 1216 gadobenate dimeglumine injections) were administered to a study cohort of 10,190 patients (49% [7982/16,237] girls and 51% [8255/16,237] boys). Incidences of 0.10% (17/16,237) for allergiclike and 0.14% (23/16,237) for physiologic reactions were observed. No severe reactions occurred. Allergiclike reaction incidences were significantly higher with gadobenate compared with gadodiamide (0.49% vs 0.04%; p < .001) and in patients who underwent abdominal or pelvic MRI examinations (0.38%) or cardiac examinations (0.55%) compared with head examinations (0.05%; p < .001 and p = .006, respectively). Physiologic reaction incidences were significantly higher in older patients (0.25% in patients 12-17 years old vs 0.03% in patients 2 to < 12 years old; p < .001) and in patients who underwent abdominal or pelvic examinations compared with head examinations (0.38% vs 0.10%; p = .002). Of 16 MRI examinations performed in patients with a prior allergiclike reaction to GBCAs, only one resulted in a repeat reaction. CONCLUSION. In this pediatric cohort, GBCA type, patient age, and MRI type were risk factors for acute reactions. Repeat reactions were rare. CLINICAL IMPACT. Providers must weigh the risks and benefits when choosing a particular GBCA to use in their practices and must consider multiple, potentially disparate risks associated with each GBCA.

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

PURPOSE: To determine safety and efficacy of retrograde pyeloperfusion for ureteral protection during cryoablation of adjacent renal tumors. MATERIALS AND METHODS: Retrospective 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. RESULTS: Technical 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. CONCLUSIONS: Retrograde 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.

Acute Adverse Events Following Gadolinium-based Contrast Agent Administration: A Single-Center Retrospective Study of 281 945 Injections.

Background Acute allergic-like and physiologic reactions occur following administration of gadolinium-based contrast agents (GBCAs) for MRI examinations. Because these reactions are uncommon, it is challenging to compare reaction rates between GBCAs and to determine risk factors. Purpose To compare reaction rates between the four GBCAs gadodiamide, gadobutrol, gadobenate dimeglumine, and gadoterate meglumine, and to determine potential risk factors for reactions. Materials and Methods This retrospective study identified all intravenous GBCA injections for MRI examinations performed at a single institution from June 1, 2009, to May 9, 2017. Reactions were identified by reviewing records from the MRI technologist, MRI nursing staff, radiologist, emergency department, and provider. Reactions were classified as allergic-like or physiologic and as mild, moderate, or severe by using American College of Radiology criteria. GBCA reaction rates and other potential risk factors were examined by using multivariable regression models with generalized estimating equations. Results Analysis included a total of 158 100 patients (median age, 55 years [interquartile range, 40-67 years], 51% women) who received a total of 281 945 GBCA injections (140 645 gadodiamide, 94 109 gadobutrol, 39 138 gadobenate, and 8053 gadoterate). At multivariate analysis, gadobenate or gadobutrol had higher rates of allergic-like reactions compared with gadodiamide (gadobenate: odds ratio [OR], 3.9 [95% confidence interval {CI}: 3.0, 5.1]; P < .001; gadobutrol: OR, 2.3 [95% CI: 1.8, 2.9]; P < .001) or gadoterate (gadobenate: OR, 4.8 [95% CI: 1.0, 23]; P = .049; gadobutrol: OR, 2.8 [95% CI: 0.6, 14]; P = .20). Physiologic reactions were more frequently observed with gadoterate (OR, 7.7 [95% CI: 2.3, 25; P = .001), gadobenate (OR, 1.8 [95% CI: 1.3, 2.5; P < .001), and gadobutrol (OR, 1.6 [95% CI: 1.3, 2.1; P < .001) administration compared with gadodiamide. Six severe allergic-like reactions (three gadobutrol, three gadobenate) occurred requiring hospitalization. Patient age (P values .025 to < .001), sex (P < .001), location (P = .006), and MRI type (P = .003 and P = .006) were associated with acute reactions. Conclusion Gadobenate and gadobutrol are associated with higher rates of allergic-like reactions compared with gadodiamide or gadoterate, and gadoterate, gadobenate, and gadobutrol are associated with higher rates of physiologic reactions compared with gadodiamide. Patient sex, age, location, and MRI type correlate with acute reaction rates. © RSNA, 2019 Online supplemental material is available for this article.

Procedure-Related Pain During Image-Guided Percutaneous Biopsies: A Retrospective Study of Prevalence and Predictive Factors.

OBJECTIVE. The purpose of this study was to evaluate the prevalence and severity of pain reported during image-guided percutaneous biopsies and to identify factors associated with increased reported pain. MATERIALS AND METHODS. In this retrospective study, a database of adult patients who underwent CT- or ultrasound-guided percutaneous core needle biopsy between July 22, 2013, and February 1, 2018, was reviewed. Data collected included patient age and sex, biopsy site, biopsy type (lesion or parenchymal), needle gauge, number of passes, use of sedation, and whether it was the patient's first recorded biopsy. The maximum procedure-related pain reported on a 0-10 numeric rating scale was recorded. Multivariable logistic regression with generalized estimating equations was used to assess the association between covariates and patient-reported pain. RESULTS. A total of 13,344 biopsy procedures were performed in 10,474 patients. Patients reported no pain (0 of 10 scale) during 9765 (73.2%) procedures. Female sex, younger age at biopsy, undergoing IV sedation, and larger needle diameter were all associated with increases in patient-reported pain. Biopsies of renal allografts were the least likely to be painful, followed by hepatic allografts. CONCLUSION. Patients typically report mild or no pain from image-guided biopsy performed by radiologists. Younger patients and women report greater pain. This information can assist preprocedural counseling and reassurance of patients and may help them predict procedure-related patient needs.

Percutaneous Cryoablation of Solitary, Sporadic Renal Cell Carcinoma: Outcome Analysis Based on Clear-Cell versus Papillary Subtypes.

PURPOSE: To evaluate treatment outcomes with percutaneous cryoablation (PCA) based on renal cell carcinoma (RCC) histology. METHODS AND MATERIALS: Patients treated with PCA for a solitary, sporadic stage T1a RCC from 2003 to 2016 were identified from a single institution's renal ablation registry. Patients with multiple tumors, history of RCC, or genetic syndromes associated with RCC (n = 60); no specific RCC subtype determined from core biopsy (n = 66); RCC subtype other than clear-cell or papillary (n = 7); or less than 3 mo of follow-up imaging (n = 5) were excluded. In total, 173 patients met study inclusion criteria. Oncologic outcomes, clinical outcomes, and complications were evaluated based on tumor subtype. RESULTS: Of the 173 patients who underwent PCA for a stage T1a RCC, 130 (75%) had clear-cell RCC (ccRCC) and 43 (25%) had papillary RCC (pRCC). Median tumor size was 2.9 cm (range, 1.3-4.0 cm). Technically successful cryoablation was achieved in all 173 patients. Local tumor recurrence developed in 6 patients with ccRCC (4.6%), new renal tumors developed in 1 patient (0.8%), and metastatic RCC developed in 1 patient (0.8%) who also had local tumor recurrence. No patients with pRCC showed local tumor recurrence, new renal tumors, or metastatic disease. The 5-year disease-free survival rate in patients with ccRCC was 88%, compared with 100% in patients with pRCC (P = .48). Nine patients (5.2%), all with ccRCC, experienced major complications (P = .11). CONCLUSIONS: Percutaneous ablation is a viable treatment option for patients with clinical stage T1a pRCC and ccRCC. Percutaneous ablation may be a very favorable treatment strategy particularly for pRCC.

Introduction of Microwave Ablation Into a Renal Ablation Practice: Valuable Lessons Learned.

OBJECTIVE: The purpose of this study was to evaluate the early outcomes of percutaneous microwave ablation (MWA) for clinical stage T1 (cT1) renal masses when performed within a high-volume ablation practice with critical emphasis on procedural safety. MATERIALS AND METHODS: A retrospective review of a percutaneous renal ablation registry identified 26 patients with a total of 27 cT1 renal masses treated with MWA between 2011 and 2017. Mean patient age was 63.8 years and 16 (61.5%) patients were male. Mean renal mass size ± SD was 2.3 ± 0.8 cm (range, 1.1-4.7 cm). The main outcome parameters investigated were technical success, local tumor progression, survival rates, and complications. Complications were categorized using the Clavien-Dindo classification system. Rates of local progression-free and cancer-specific survival (PFS and CSS, respectively) were estimated using the Kaplan-Meier method. RESULTS: Technical success was 100% on contrast-enhanced CT or MRI performed immediately after renal MWA. Twenty-four patients (92%) with 25 tumors had follow-up imaging for 3 months or longer (mean, 20.6 ± 11.6 months), with no local tumor recurrences identified. Estimated 3-year local PFS and CSS were 96% and 94%, respectively. The overall complication rate was 19.2%; two patients (7.7%) experienced minor complications (grade I or II) and three patients (11.5%) experienced major bleeding or urinary-related complications (grade III or higher), including one death. CONCLUSION: This study suggests that percutaneous MWA is a promising minimally invasive treatment option for cT1 renal masses. Nonetheless, major bleeding and urinary-related complications can occur, and further studies are needed to determine optimal patient and tumor selection for renal MWA.

Percutaneous Cryoablation of Renal Cell Carcinoma with Sinus Vein Involvement Based on Preprocedural Imaging.

PURPOSE: To assess feasibility, safety, and oncologic outcomes of cryoablation in treatment of renal cell carcinoma (RCC) with extension into adjacent renal sinus vein. MATERIALS AND METHODS: Review of an internally maintained renal ablation registry identified 7 patients (4 men and 3 women; median age 62 y; age range, 45-91 y) who underwent percutaneous cryoablation of RCC with imaging consistent with extension of tumor into an immediately adjacent renal sinus vein. Four of 7 (57%) patients had recurrent tumors following prior partial nephrectomy. Three of 7 patients (43%) had solitary kidneys. RESULTS: Median tumor size was 4.3 cm (range, 1.9-5.0 cm). Biopsy showed RCC in 6 of 7 patients. Technical success was achieved in 6 of 7 tumors (86%) There was a single Clavien grade 3 major complication. Median hospital stay was 1 night (range, 1-3 nights). Follow-up imaging performed in the 6 successfully treated patients at median 11 months (range, 2-101 months) showed no local tumor progression. In 2 patients with solitary kidneys, estimated glomerular filtration rate declined from 63 mL/min/1.73 m2 to 45 mL/min/1.73 m2 and 67 mL/min/1.73 m2 to 40 mL/min/1.73 m2 at 101 months and 12 months following treatment, respectively. Estimated glomerular filtration rate remained > 60 mL/min/1.73 m2 in the remaining patients. CONCLUSIONS: In this small select group of patients, percutaneous cryoablation afforded a safe and, based on early outcomes, effective means of providing local control of locally invasive RCC. Percutaneous cryoablation may obviate the need for nephrectomy in similar patients.

Outcomes of Ultrasound-Guided Thrombin Injection of Nongroin Arterial Pseudoaneurysms.

PURPOSE: To evaluate success and complication rates of percutaneous ultrasound-guided thrombin injection of nongroin pseudoaneurysms (PSAs). MATERIALS AND METHODS: Retrospective review of a prospectively maintained institutional database yielded 39 cases of arterial PSAs occurring at nongroin sites that were treated with percutaneous ultrasound-guided thrombin injection between 2000 and 2016 (average patient age 69.2 y ± 14.0). Of PSAs, 74.4% (29/39) arose in the upper extremities, and 92.3% (36/39) were iatrogenic. The brachial artery was the most commonly affected vessel (51.3% [20/39]), and arterial access was the most common cause (56.4% [22/39]). Average overall PSA size was 2.4 cm (range, 0.5-7.2 cm); average amount of thrombin injected was 320 IU (range, 50-2,000 IU). Technical success was defined as absence of flow within the PSA immediately after thrombin injection. Treatment success was defined as sustained thrombosis on follow-up imaging obtained at 1-3 days after treatment. RESULTS: Technical and treatment success rates of thrombin injections were 100% (39/39) and 84.8% (28/33), respectively. Longer term follow-up imaging (average 71 d; range, 12-201 d) was available for 7 of the treatment successes with 100% (7/7) showing sustained thrombosis. Comparing treatment successes and failures, there was no significant difference in average PSA size (2.3 cm vs 2.0 cm, P = .51) or average amount of thrombin injected (360 IU vs 180 IU, P = .14). There were no complications. CONCLUSIONS: Ultrasound-guided thrombin injection is a safe, efficacious treatment option for PSAs arising in nongroin locations.

Effects of Aspirin Therapy on Ultrasound-Guided Renal Allograft Biopsy Bleeding Complications.

PURPOSE: To determine if patient aspirin exposure and timing affect bleeding risk after renal allograft biopsy. MATERIALS AND METHODS: Review of 6,700 renal allograft biopsies (in 2,362 unique patients) was performed. Median patient age was 53.0 years [interquartile range 43.0, 62.0]; 56.2% of patients were male. Of biopsies, 4,706 (70.2%) were performed in patients with no aspirin exposure within 10 days of biopsy; 664 (9.9%), were performed within 8-10 days of aspirin exposure; 855 (12.8%), within 4-7 days; and 475 (7.1%), within 0-3 days. Follow-up to 3 months after the procedure was completed in all patients. Biopsies were categorized as protocol or indication; 19.7% were indication biopsies. Bleeding complications were graded based on SIR criteria. Logistic regression models examined the association between aspirin use and bleeding events. RESULTS: Rate [95% confidence interval] of major bleeding complications was 0.24% [0.14, 0.39], and rate of any bleeding complication was 0.66% [0.46, 0.90]. Bleeding events were significantly associated with patients undergoing indication biopsies compared with protocol biopsies (odds ratio [OR] 2.27, P = .012). Patient factors associated with major bleeding complications in multivariate models included estimated glomerular filtration rate (OR 0.61, P = .016) and platelet count (OR 0.64, P = .033). Aspirin use was not significantly associated with increased risk of bleeding complication except for use of 325 mg of aspirin within 3 days of biopsy (any complication OR 3.87 [1.12, 13.4], P = .032; major complication OR 6.30 [1.27, 31.3], P = .024). CONCLUSIONS: Renal allograft biopsy bleeding complications are very rare, particularly for protocol biopsies. Use of 325 mg of aspirin within 3 days of renal allograft biopsy was associated with increased bleeding complications.

Utility of PET/CT After Cryoablation for Early Identification of Local Tumor Progression in Osseous Metastatic Disease.

OBJECTIVE: The purpose of this study is to evaluate the utility of combined PET/CT for the detection of early local tumor progression after cryoablation of bone metastases. MATERIALS AND METHODS: A retrospective single-institution review revealed 61 consecutive patients with 80 separate bone metastases treated with cryoablation who were evaluated with a preablation PET/CT and at least two postablation PET/CT examinations between September 2007 and July 2015. Patients were excluded if they had local therapy or pathologic fracture after ablation. The patients were grouped according to postcryoablation disease status (i.e., local tumor progression or not) and PET radiotracer (i.e., 11C-choline or 18F-FDG) used. The maximum standardized uptake value (SUVmax) ratio (i.e., ratio of SUVmax to blood pool) was calculated within each osseous metastasis before and after cryoablation, and these were then compared between groups. RESULTS: Of the 61 patients and 80 ablations performed, 32 patients were imaged with FDG PET/CT and 29 were imaged with 11C-choline PET/CT. Twenty-three patients imaged with FDG and 13 patients imaged with 11C-choline had evidence of local tumor progression on all postablation PET/CT examinations. The SUVmax ratio was significantly higher in patients with local tumor progression on the first and most remote postcryoablation PET/CT examinations for both FDG and 11C-choline (p < 0.001 in all cases). There was no significant difference in the postablation systemic therapy between the groups with and without local tumor progression. CONCLUSION: Increased SUVmax ratio in patients after cryoablation for osseous metastatic disease should raise concern about local tumor progression independently of time after ablation.

Image-Guided Thermal Ablative Therapies in the Treatment of Sarcoma.

OPINION STATEMENT: Percutaneous thermal ablation, including microwave ablation (MWA), radiofrequency ablation (RFA), and cryoablation, is a well-established focal treatment option for primary and metastatic malignancies. While published literature specific to ablation of sarcomas is relatively lacking compared with non-sarcomatous malignancies, what is available is promising. In situations where a focal treatment option is desired, strong consideration should be given to percutaneous thermal ablation, in addition to surgery and radiation therapy. A significant advantage of percutaneous thermal ablation over surgery and radiation includes the repeatability of ablation, as there is no absolute limit on the number of times an ablation can be performed. Compared with surgery, ablation offers the potential of decreased recovery time, a less invasive procedure, and is often performed in patients deemed not medically fit for surgery.

Percutaneous Cryoablation of Extraabdominal Desmoid Tumors: A 10-Year Experience.

OBJECTIVE: Extraabdominal desmoid (EAD) tumors pose a therapeutic challenge because they often recur locally and behave aggressively. Accepted management options include surgery, radiation, chemotherapy, and observation. The objective of this study was to assess the safety and efficacy of percutaneous cryoablation for the treatment of EAD tumors. MATERIALS AND METHODS: A retrospective search of our cryoablation database was performed to identify patients with EAD tumors treated with percutaneous cryoablation between June 15, 2004, and June 15, 2014. During this 10-year time period, we treated 18 patients with 26 discrete tumors during 31 treatment sessions. After cryoablation, contrast-enhanced MRI or CT was performed. Any enhancing soft tissue was considered viable EAD tumor and was measured in three planes. RESULTS: Of the 26 EAD tumors treated, follow-up imaging with IV contrast material was available for 23 tumors. The mean imaging follow-up was 16.2 ± 20.0 (SD) months. All 31 sessions were technically successful procedures. No residual viable EAD tumor was observed in nine of 23 tumors (39.1%). Some degree of volume reduction was evident in 22 of 23 tumors (95.7%). Progressive disease was observed in one of the 23 tumors (4.3%). Of the cases with residual or progressive disease, the recurrence occurred at the margin of the treated tumor in all cases. No major complications were observed, and none of the complications was more severe than Clavien-Dindo grade I. CONCLUSION: Percutaneous cryoablation is a safe, effective, and repeatable treatment for achieving local control of EAD tumors.