Transrenal Ureteral Embolization Utilizing Amplatzer Vascular Plugs and N-Butyl Cyanoacrylate Glue.

This retrospective study presents three consecutive patients who underwent bilateral ureteral occlusion using the Amplatzer vascular plugs and N-butyl cyanoacrylate glue sandwich method. The patients were 63- and 65-year-old males and a 79-year-old female. Indications for the procedure included severe cystitis and complex vesicular fistulas unresponsive to urinary diversion. All three patients had immediate resolution of urinary leakage, resulting in symptom relief throughout the follow-up period. There were no procedure-related complications or side effects.

Skin-to-tumor Distance Predicts Treatment Failure of T1A Renal Cell Carcinoma Following Percutaneous Cryoablation.

OBJECTIVE: To determine the impact of skin-to-tumor (STT) distance on the risk for treatment failure following percutaneous cryoablation (PCA). METHODS: We retrospectively reviewed patients who underwent PCA with documented T1a recurrent renal cell carcinoma (RCC) at 2 academic centers between 2005 and 2015. Patient demographics, tumor characteristics, and perioperative and postoperative course variables were collected. Additionally, we measured the STT distance by averaging the distance from the skin to the center of the tumor at 0°, 45°, and 90° on preoperative computed tomography imaging. RESULTS: We identified 86 patients with documented T1a RCC. The mean age at the time of surgery was 69 years (range: 37-91 years), and the mean tumor size was 2.7 cm (range: 1.0-4.0 cm). With a mean follow-up of 24 months (range: 3-63 months), 11 (12.8%) treatment failures occurred. Patients with treatment failure had significantly higher mean STT distance than those without: 11.0 cm (range: 6.3-20.1 cm) compared to 8.4 cm (range: 4.4-15.2 cm), respectively (P = .002). STT distance was an independent predictor of treatment failure (odds ratio: 1.32, 95% confidence interval: 1.04-1.69, P = .029). STT distance greater than 10 cm had a fourfold increased risk of tumor treatment failure (odds ratio: 4.43, 95% confidence interval: 1.19-16.39, P = .018). Tumor size, R.E.N.A.L. Nephrometry score, and number of cryoprobes placed were not associated with treatment failure. CONCLUSION: STT, an easily measured preoperative variable, may inform the risk of RCC treatment failure following PCA.

Improving the Odds: Intercostal Metal Coils Mark Area to Resect in Rib Lesions.

Precise localization of a rib lesion for its resection remains a challenge because of multiple factors including nonpalpable pathology, unfavorable body habitus, inaccurate clinical examination, and unreliable rib count on physical examination, unfavorable lesion location within a rib (its posterior aspect), and resection of sclerotic lesions with grossly intact rib cortex. We describe a novel rib localization technique that eliminates potential mistakes and avoids resection of an inappropriate rib. Our method of rib localization includes placement of metallic coils by interventional radiologists under computed tomography guidance where two coils are deployed within the intercostal spaces, one superior and one inferior to the rib lesion. Intraoperative use of fluoroscopy results in precise localization of rib lesions even in cases where the pathology is not grossly apparent. We implemented this approach in 2014 and have since performed it in five patients for both lytic and sclerotic lesions. Placement of markers superficial to the intercostal spaces resulted in their displacement in one case. Successfully, we removed the correct ribs in each patient without technical difficulties or complications. Our series demonstrates a novel strategy for a highly accurate and relatively easy way to identify the exact portion of the rib for surgical resection. Intercostal space positioning of the coil markers superior and inferior to the lesion prevents their dislodgement during patient transport and positioning on the operating room table, which improves rib identification accuracy and reliability. When combined with intraoperative fluoroscopy, it will greatly eliminate resection of incorrect ribs.

Predictors of Complications After Percutaneous Image-Guided Renal Cryoablation for T1a Renal Cortical Neoplasms.

PURPOSE: To determine the incidence and predictors of major complications in patients undergoing percutaneous cryoablation (PCA) for small renal masses. METHODS: We performed a retrospective analysis of patients undergoing PCA from 2005 to 2012. We analyzed demographic, radiographic, and complication data. We defined complications as any deviation from the expected postoperative course. We determined predictors of complications. RESULTS: A total of 190 patients were included in the study. The mean age was 69 years, and 132 (69%) were males. The mean tumor diameter was 2.2 cm (0.8-4.0 cm). The mean number of probes utilized per procedure was 2.3. We observed 16 (8.4%) complications including 14 Clavien grade I, which includes 6 (2%) large renal/retroperitoneal hematomas, 4 (2%) pneumothoraxes, 2 (1%) urinary tract infections, and 2 (1%) atrial fibrillations. There were two (1%) Clavien grade II complications (intestinal perforations). In univariable analysis, larger tumors and more probes were associated with higher risk of complications (all ps < 0.05). In multivariable analysis, larger tumor dimension (odds ratio [OR] = 2.85; 95% confidence interval [CI] = 1.34, 6.05; p = 0.006) was independently associated with major complications. After multivariable adjustments for patient's characteristics such as age, gender, American Society of Anesthesiologists, year of surgery, and histopathology, larger tumor dimension (OR = 2.85; 95%CI = 1.34, 6.05; p = 0.006) and more cryoablation probes (OR = 1.94; 95%CI = 1.36, 2.75; p < 0.001) were independently associated with higher risk of major complications. CONCLUSIONS: In a cohort of patients undergoing PCA for T1a small renal mass, larger tumor dimension and more cryoablation probes were independently associated with higher risk of complication. Although PCA is relatively safe and the major complications are infrequent, careful patient selection is crucial.

Salvage Percutaneous Cryoablation for Locally Recurrent Renal-Cell Carcinoma After Primary Cryoablation.

BACKGROUND: The management of locally recurrent renal-cell carcinoma (RCC) following cryoablation remains a clinical dilemma. There is limited data regarding the management of locally recurrent disease in the setting of patients who have failed initial percutaneous cryoablation (PCA). We evaluate and report our experience with salvage PCA for local recurrence following renal cryoablation failure. PATIENTS AND METHODS: We reviewed our experience with patients who underwent salvage PCA for local biopsy proven RCC recurrence following primary cryoablation procedures. Complications and oncologic outcomes were evaluated. Recurrence-free survival after primary and repeat cryoablation was plotted using the Kaplan-Meier curves. RESULTS: A total 250 patients underwent primary cryoablation for RCC and 20 (8%) patients were identified who underwent repeat PCA for 21 locally recurrent tumors. The mean tumor size was 2.4 cm. Biopsy revealed clear cell in 14 patients, three papillary and four chromophobe RCC. All repeat cryoablation procedures were completed successfully, with no treatment failures on postprocedure imaging. There were no complications or deaths. With the median follow-up of 30 months (range 7-63), 3 (15%) patients experienced local recurrence. One patient had an enhancing lesion at 13 months following repeat PCA and underwent a third PCA. Two patients had recurrence at 6 and 35 months respectively and underwent successful laparoscopic partial nephrectomy. Local recurrence-free, metastasis-free and cancer-specific survival rates were 85%, 100%, and 100% respectively. Limitations include retrospective design and small number of patients. CONCLUSIONS: Repeat PCA after primary cryoablation failure is feasible, has a low complication rate, and acceptable short-term oncologic outcomes. Further studies with durable follow-up are required.

Radiation Exposure During Percutaneous Ablation of Small Renal Masses: A Multi-Institutional Multimodality Analysis.

OBJECTIVE: To understand the effective radiation dose during percutaneous cryoablation (CA) and radiofrequency ablation (RFA) and characterize variables that may affect the individual dose. MATERIALS AND METHODS: The effective radiation dose was determined by conversion of the dose-length product from CT scans performed during percutaneous CA or RFA for patients with solitary renal masses (<4 cm) at four academic centers. Radiation dose per case was compared between patients and institutions using multivariate and univariate analysis. Lifetime attributable risk of cancer was calculated for each institution and utilized to determine the number needed to harm for a range of ages at the time of exposure. RESULTS: One hundred twenty-three patients met the inclusion criteria with a mean age of 71 years. Sixty-nine percent of patients were male, mean body-mass index (BMI) was 29.4, and mean tumor size was 2.2 cm. The mean effective radiation dose per ablation was 40 mSv (range 3.7-147). On multivariate analysis, only BMI and institution were associated with the radiation dose. No significant difference in radiation exposure was seen for RFA or CA procedures. CONCLUSIONS: Radiation exposure during percutaneous ablation is similar to a multiphase CT scan. However, there is wide variability in individual treatment exposure, varying from 3.7 to 147 mSv, depending primarily on institution and BMI. Standardization of protocols is required to achieve as low as reasonably achievable levels of radiation.

Comparison of outcomes in patients undergoing percutaneous renal cryoablation with sedation vs general anesthesia.

OBJECTIVE: To compare the efficacy and safety of local anesthesia with conscious sedation (LACS) with general anesthesia (GA) in patients undergoing percutaneous renal cryoablation (PRC) for renal cortical neoplasms. METHODS: We performed a retrospective review of patients undergoing PRC between 2003 and 2013. Patient demographics, tumor characteristics, and perioperative and postoperative follow-up data were recorded and analyzed. We compared 3 principal outcomes across the GA and LACS groups: anesthesia-related outcomes, treatment failure, and complications. RESULTS: A total of 235 patients with available data were included. Of these, 82 underwent PRC under GA and 153 patients under LACS. The 2 groups were similar with regard to age, gender, body mass index, American Society of Anesthesiologists score, tumor features, preoperative serum creatinine level, and hematocrit value. The GA and LACS groups had a similar percentage of patients with biopsy-proven renal cell carcinoma (68.5% and 64.2%, respectively; P = .62). The mean follow-up time for GA and LACS was 37 and 21 months, respectively (P <.0001). The mean procedure time for GA was significantly longer compared with LACS (133 vs 102 minutes; P <.001), and the mean hospital stay was shorter under LACS (1.08 vs 1.95 days; P <.0001). There was no difference in immediate failure (0% and 1.9%; P = .051) or recurrences (11% and 3.9%, respectively; P = .051) between GA and LACS groups. There was no difference in intraoperative and postoperative treatment-related complications between the 2 groups. CONCLUSION: PRC for small renal masses under LACS is effective and safe. PRC with LACS has the advantage of decreased procedure time and a shorter hospital stay.

Image-guided percutaneous renal cryoablation: preoperative risk factors for recurrence and complications.

OBJECTIVE: To investigate the value of the R.E.N.A.L nephrometry scoring system in predicting treatment success for image-guided percutaneous cryoablation (PCA). PATIENTS AND METHODS: The study included 139 patients with renal masses treated with PCA. Preoperative computed tomography or magnetic resonance images were reviewed by a urology resident. The primary endpoint variable was incomplete treatment or tumour recurrence. R.E.N.A.L. scores were categorized into low (4-6), moderate (7-9), and high (10-12). Logistic regression analysis was conducted to predict tumour recurrence. Additional variables collected included age at surgery, American Society of Anesthesiologists score, lesion size, skin-to-tumour distance, skin-to-hilum distance, and number of treatment cryoprobes. RESULTS: At a median follow-up of 24 months, there were 10 tumour recurrences (six moderate and four high R.E.N.A.L. score categories). Nephrometry score and number of probes used were not associated with recurrence (odds ratio [OR] 1.02, P = 0.9 and P = 0.53, respectively). The tumour distances for patients with recurrence and no recurrence were 10.8 cm and 8.5 cm, respectively (P ≤ 0.05), the skin-to-tumour distance was associated with treatment failure (OR 1.24, P = 0.015); for each unit increase in the mean value, patients were 1.5 times more likely to have a tumour recurrence (95% confidence interval [CI] 1.04-1.72). The model that best predicted complications included the number of probes used (P = 0.002) and R.E.N.A.L. score (OR 1.35, P = 0.027). For each additional probe used, patients were twice as likely to have complications (OR 1.98, 95% CI 1.28-3.05). With each unit increase in R.E.N.A.L. score, patients were 1.5 times more likely to experience a complication (OR 1.49, 95% CI 1.05-2.11). CONCLUSIONS: An increased skin-to-tumour distance is associated with a higher risk of treatment failure after PCA. Furthermore, an increase in both R.E.N.A.L nephrometry score and number of probes used was associated with an increased risk of complications after PCA. The R.E.N.A.L. nephrometry score as a measure of tumour complexity was not associated with tumour recurrence.

First Prize (tie): Hemorrhage following percutaneous renal surgery: characterization of angiographic findings.

PURPOSE: Percutaneous surgery is an established approach to a spectrum of renal pathology, and hemorrhage is the most concerning complication of this technique. We determined the frequency of postoperative hemorrhage requiring selective angioembolization (sae), the efficacy of this approach, and characterized the angiographic findings. METHODS: We reviewed our database of 4695 patients who underwent percutaneous renal surgery and identified patients requiring SAE for postoperative hemorrhage. Angiographic findings were recorded and efficacy of SAE documented. RESULTS: Patients undergoing percutaneous stone extraction (PSE; 3685), percutaneous antegrade endopyelotomy (PAE; 850), and upper-tract transitional cell carcinoma (UTTCC) resection (160) were reviewed. We identified 57 patients requiring SAE (1.2%) who underwent 44 PSEs (77.2%), 7 PAEs (12.3%), and 6 UTTCC resections (10.5%). This represented 1.2%, 0.8%, and 3.2% of all PSE, PAE, and UTTCC resections, respectively. Angiography revealed treatable lesions in 94.7% of patients. Overall, 64 angiographic findings were encountered including 30 pseudoaneurysms (53% of patients, 47% of findings), 14 arteriovenous fistulas (AVFs) (25% of patients, 22% of findings), and 14 instances of contrast extravasation (25% of patients, 22% of findings). Two arterial dissections and one instance each of a hypervascular area, a vascular "cut-off" sign, and a fistula between an artery and the percutaneous tract were identified. One bleeding vessel identified at the base of a UTTCC resection was not amenable to embolization. Ten patients (17.5%) had >or=1 angiographic finding. Three patients (5.3%) had no angiographic findings to account for hemorrhage. No angioembolization-related complications occurred. Complete resolution of bleeding was observed in 54 patients (95%). CONCLUSIONS: Major hemorrhage requiring intervention after percutaneous renal surgery is uncommon. The most common angiographic finding is arterial pseudoaneurysm, followed by arteriovenous fistula, and contrast extravasation. In 95% of cases angiography reveals a demonstrable and treatable etiology. This strongly supports the first-line use of angiography for intractable bleeding in this setting.

Selective arterial prostatic embolization (SAPE) for refractory hematuria of prostatic origin.

OBJECTIVES: To assess SAPE as an alternative treatment option in patients with refractory hematuria of prostatic origin. METHODS: A retrospective analysis of charts from 10 patients. Two patients were excluded from the analysis because of severe atherosclerotic disease that prevented selective angiography of the pelvic vasculature. Therefore, 8 patients, mean age of 78.3 +/- 7.1 years with a history of refractory hematuria of prostatic origin were analyzed. All patients failed conventional therapy. The selective embolization procedures were performed between 2000 and 2006. Success was monitored with postembolization angiography and cessation of hematuria clinically. RESULTS: Of the 8 patients, 6 had a history of adenocarcinoma of the prostate (mean Gleason Grade 7, range 5 to 9); 4 were previously treated with external beam radiation. The remaining patient's histories were consistent with benign prostatic hypertrophy. SAPE was technically successful in all 8 patients and resulted in immediate cessation of gross hematuria. Mean follow-up postembolization was 20.0 months (range 1.5 to 86.3 months). One patient had gross hematuria develop 14 months after embolization that was attributed to a bladder tumor recurrence. One patient with T4 prostate cancer had a rectovesical fistula develop 1 month after embolization. CONCLUSIONS: SAPE results in cessation of refractory gross hematuria in patients with benign prostate hyperplasia and patients with prostate cancer previously treated with radiotherapy. SAPE may be considered an effective treatment for gross hematuria in patients with refractory hematuria regardless of the cause (radiation, cancer and/or hyperplasia).

Successful conservative management of colorenal fistula after percutaneous cryoablation of renal-cell carcinoma.

BACKGROUND: Cryoablation is an increasingly utilized treatment for renal-cell carcinoma. We describe the first reported case of colorenal fistula resulting from percutaneous renal cryoablation. CASE REPORT: A 63-year-old man with hematuria was found to have an enhancing renal mass that was treated with percutaneous CT-guided cryoablation. Two months later, he presented with lower urinary-tract symptoms, and CT imaging revealed a colorenal fistula at the ablation site. Ureteral stent placement resulted in resolution of the fistula. CONCLUSIONS: Contrary to previously reported animal and clinical studies, our case report demonstrates that it is possible to incur serious harm to the renal collecting system as a result of percutaneous renal cryoablation. In stable patients, an attempt at conservative management of a fistula should precede extensive reconstructive efforts.