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Purpose: With the incidence of renal cell carcinoma on the rise treatment options for the small renal mass have broadened. Cryoablation is increasingly used as a therapeutic option for renal tumors in select cases. However, studies with long-term oncologic outcomes are sparse. We evaluated the long-term oncologic outcomes of laparoscopic renal mass cryoablation., Materials and Methods: We reviewed our laparoscopic cryoablation database for patients treated with laparoscopic cryoablation from October 1997 to February 2005. Patients with less than 3 months of followup were excluded from study. Patient and tumor characteristics, and perioperative outcomes, including complications, were recorded. Recurrence-free, cancer specific and overall survival was analyzed using Kaplan-Meier curves., Results: A total of 142 tumors in 138 consecutive patients were treated with laparoscopic cryoablation. Mean age of the cohort was 66.35 years. Of the patients 99 (71.7%) were male and 39 (28.3%) were female. Mean body mass index was 29.15 kg/m(2) and median ASA score was 3. A solitary kidney was present in 23 patients (16.2%). Mean tumor size on cross-sectional imaging was 2.4 cm. The mean preoperative and postoperative estimated glomerular filtration rate was 66.72 and 61.00 ml per minute, respectively. The postoperative estimated glomerular filtration rate was determined at a mean ± SD of 15.17 ± 10.99 months of followup. The median R.E.N.A.L. nephrometry score was 5. Of the 142 tumors 100 were diagnosed as renal cell carcinoma after histopathological examination of the biopsy specimen. At 3, 5 and 10 years in patients diagnosed with renal cell carcinoma estimated recurrence-free survival was 91.4%, 86.5% and 86.5%, estimated cancer specific survival was 96.8%, 96.8% and 92.6%, and estimated overall survival was 88.7%, 79.1% and 53.8%, respectively. Mean followup was 98.8 ± 54.2 months in those diagnosed with renal cell carcinoma. Mean time to recurrence was 2.3 years. The latest experienced recurrence was 4.4 years after laparoscopic cryoablation. There was a postoperative complication rate of 10.6% with a total of 15 complications., Conclusions: Laparoscopic cryoablation achieves good long-term oncologic outcomes for localized small renal masses. It can safely be used in patients who cannot undergo or are unwilling to accept the risks of partial nephrectomy. Mean time to recurrence was 2.3 years and all recurrences developed within 4.4 years of initial treatment., (Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Objective: To analyze our 15-year experience with small renal masses ablation and present oncologic and functional outcomes of laparoscopic cryoablation (LCA) and percutaneous cryoablation (PCA)., Materials and Methods: We identified patients who underwent LCA (n = 275) or PCA (n = 137) for small renal masses between 1997 and 2012. Differences in overall survival (OS) and recurrence-free survival (RFS) were analyzed using a log-rank test. Cox proportional hazard ratios model was used to determine factors that predicted OS. Fit proportional hazard risk ratios were also calculated to determine if there were any factors that affected tumor recurrence., Results: Tumor sizes were equal between the 2 groups; however, tumors in the PCA group were more complex. The overall (7.27% and 7.29%) and major complications (0.7% and 3.6%) were similar. The estimated probability of 5-year OS for LCA and PCA was 89% and 82%, respectively. The estimated probability of the 5-year RFS for LCA and PCA was 79% and 80%, respectively. Heart disease (hazard ratio, 2.15; 95% confidence interval, 1.35-3.41; P = .001) and history of disease recurrence (hazard ratio, 2.49; 95% confidence interval, 1.60-3.86; P = .001; P <.0001) were predictors of death. The median follow-up time for the LCA group (4.41 years [1.67-6.91 years]) was longer than the PCA group (3.15 years [1.37-4.08 years]; P = .0001)., Conclusion: We found no significant difference in OS or RFS at 5 years between the 2 groups. Tumor size and anterior location affected local recurrence rates, and these factors should be taken into consideration when choosing the appropriate treatment plan. RENAL nephrometry score or type of cryoablation was not associated with tumor recurrence., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: To evaluate the efficacy and safety of probe ablative therapy as salvage treatment for renal tumor in von Hippel-Lindau (VHL) patients after previous partial nephrectomy (PN)., Methods: Medical records of VHL patients undergoing probe ablative treatment for renal tumors from March 2003 to January 2010 at our institution were retrospectively analyzed., Results: Fourteen VHL patients who were submitted to salvage probe ablative therapy were included in the analysis. Twelve patients (85%) had a solitary kidney. Overall, 33 tumors were ablated by either percutaneous cryoablation (P-Cryo) (n of procedures = 13), radiofrequency ablation (RFA) (n = 14), and laparoscopic cryoablation (L-Cryo) (n = 3). Average maximal renal tumor diameter was 2.6 ± 1 cm. Average ablation time was 18.3 ± 2.1 minutes for P-Cryo, 36.7 ± 17 minutes for RFA, and 17.3 ± 4 minutes for L-Cryo. All procedures were successfully completed without transfusions and intraoperative complications. No early postoperative complications were recorded. Postoperative decline in renal function was minimal and not clinically significant. With a mean follow-up of 37.6 months (range 12-82), 4 patients had a suspicious recurrence on computed tomography/magnetic resonance imaging (CT/MRI) scan and in 3 of them a re-ablation was performed. Actuarial overall and cancer-specific survivals were 92% and 100%, respectively., Conclusions: Probe ablative therapy seems to represent a suitable treatment option for VHL patients with a previous history of PN as it offers a repeatable operation, with a high technical success rate and causing minor changes in renal function., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Percutaneous cryoablation of renal tumors requires a number of important steps for success and relies heavily on imaging for treatment planning, intraprocedural guidance and monitoring, detection of untreated tumor, and surveillance for disease progression. Imaging-guided percutaneous cryoablation has several advantages over laparoscopic cryoablation. In particular, computed tomography (CT) and magnetic resonance (MR) imaging allow global evaluation of the ablation zone and an accurate depiction of the treatment margin. Ultrasonography allows real-time guidance of probe placement but cannot help depict ice ball formation as accurately as CT or MR imaging. Multiphasic CT or MR imaging should be performed at structured intervals following ablation. Treated tumors are expected to decrease in size over time, and lesion growth and internal or nodular enhancement are suspicious for tumor recurrence or progression. Complications include probe site pain, hematoma, incomplete ablation, and recurrent tumor. Current limitations of percutaneous cryoablation include the inability to control hemorrhage without intraarterial access and a lack of long-term follow-up data. Nevertheless, percutaneous cryoablation is an effective choice for minimally invasive nephron-sparing treatment of renal tumors.

Purpose: Percutaneous imaging guided tumor ablation has an increasingly prominent role as minimally invasive treatment for renal tumors. Precise cryoprobe placement is essential for successful ablation. CT-Nav is a novel stereotactic surgical navigation system with the potential to achieve precise percutaneous cryoprobe placement while decreasing radiation exposure compared to conventional computerized tomography guided procedures., Materials and Methods: We performed a prospective pilot study to evaluate the technical feasibility, safety and accuracy of the system during renal cryoablation. Patients with enhancing renal masses amenable to renal cryoablation underwent preoperative computerized tomography with a preplaced tracking sensor taped to the body. Using a stereroscopic infrared camera the tracking sensor was located 3-dimensionally and a tracking handle was used to guide the cryoprobe percutaneously based on preoperative preloaded computerized tomography. Demographic and perioperative data were added prospectively to an institutional review board approved database. Immediately after cryoprobe placement computerized tomography was repeated to confirm placement accuracy., Results: A total of 13 tumors in 10 patients were successfully cryoablated with the novel navigational system. Mean tumor size was 2.2 cm. Preoperative biopsy revealed renal cell carcinoma in 9 cases. Mean operative time was 155 minutes. No intraoperative or postoperative complications were noted. Mean length of stay was 9.5 hours. Mean targeting registration error was 4.2 mm., Conclusions: Stereotactic percutaneous cryoablation for renal tumors offers the potential for safe, precise needle placement., (2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Over the past decade, a number of probe ablative therapies have emerged for the treatment of patients with localized renal tumors. Cryoablation and radiofrequency ablation (RFA) have been studied in the greatest detail. We present the results of 164 laparoscopic cryoablations and 82 percutaneous RFAs performed in our institution and compare them retrospectively in terms of complications, impact on renal function, follow-up imaging, and oncologic outcomes. Comparison of cryotherapy versus RFA revealed that mean tumor size was similar (2.56 cm vs 2.51 cm); however, the cryoablation group had a greater number of anteriorly located tumors (39% vs 10%), as well as fewer central tumors (6% vs 37%) and fewer solitary kidneys (24% vs 49%). Mean thermal treatment time was 19.3 minutes versus 32.2 minutes in the cryoablation and RFA groups, respectively. Radiologic evidence of tumor recurrence or persistence of disease was noted in 3 patients (1.8%) who underwent cryoablation and in 9 (11.1%) who were treated with RFA. All of have been successfully treated with repeat ablation/nephrectomy, or they are currently under observation. Complication rates were minimal in both groups; no significant impact on mean serum creatinine levels was noted. Cancer-specific survival following cryotherapy was 98% at a median follow-up of 3 years and 100% for RFA at 1-year median follow-up. Cryoablation and RFA are developmental nephron-sparing options. Early results are encouraging for both forms of probe ablation in terms of early oncologic control, preservation of renal function, and low complication rates. Longer-term oncologic data are necessary so that the true value of these treatment modalities can be determined.

Purpose: We report intermediate term oncological followup data on 56 patients undergoing laparoscopic renal cryoablation, of whom each completed a 3-year followup., Materials and Methods: Since September 1997, 56 patients undergoing laparoscopic renal cryoablation have completed a followup of 3 years each. The postoperative followup protocol comprised serial magnetic resonance imaging (MRI) at 1 day, months 1, 3, 6, 12, 18 and 24, and yearly thereafter for 5 years. Computerized tomography guided needle biopsy of the cryolesion was performed 6 months postoperatively and repeated if MRI findings were abnormal. Followup data were obtained prospectively., Results: For a mean renal tumor size of 2.3 cm mean intraoperative size of the created cryolesion was 3.6 cm. Sequential mean cryolesion size on MRI on postoperative 1 day, and at 3 and 6 months, and 1, 2 and 3 years was 3.7, 2.8, 2.3, 1.7, 1.2 and 0.9 cm, representing a 26%, 39%, 56%, 69% and 75% percent reduction in cryolesion size at 3 and 6 months, and 1, 2 and 3 years, respectively. At 3 years 17 cryolesions (38%) had completely disappeared on MRI. Postoperative needle biopsy identified locally persistent/recurrent renal tumor in 2 patients. In the 51 patients undergoing cryotherapy for a unilateral, sporadic renal tumor 3-year cancer specific survival was 98%. There was no open conversion, kidney loss, urinary fistula, dialysis requirement, or perirenal or port site recurrence in any patients., Conclusions: Three-year outcomes following renal cryoablation are encouraging. Longer term (5-year) data are necessary to determine the proper place of renal cryotherapy among minimally invasive, nephron sparing options.

Purpose: We determined the short-term and long-term sequelae of intentional cryoablation of the renal pelvicaliceal system and evaluated whether continuous irrigation of the renal pelvicaliceal system with warm saline protects it against cryo-injury., Materials and Methods: In 12 swine open bilateral renal cryoablation using an argon gas based system was performed to create a cryolesion in the lower pole that was intentionally extended into the collecting system. A single cryoprobe was used to create a 3 cm ice ball in group 1 (6 animals) and 2, 3 mm cryoprobes were used to create a 4.5 cm ice ball in group 2 (6). In all 12 right kidneys pelvicaliceal warming (range 38C to 42C) was performed using continuous retrograde saline irrigation through an indwelling 5Fr ureteral catheter. In all 12 left kidneys cryoablation was performed without pelvicaliceal warming. Real-time confirmation of caliceal involvement by the cryolesion was obtained by retrograde ureteropyelogram. Immediately after cryo-injury 6 left and 6 right kidneys were harvested for histology and the animals with a solitary kidney were followed for 1 to 3 months., Results: Nadir cryoprobe tip temperature was -136C with a mean cryolesion time of 10.5 minutes. Cryolesion size was comparable in the right vs left kidneys in groups 1 and 2 (2.9 vs 3.0 and 4.7 vs 4.6 cm, respectively). Similarly cryoablation time was comparable between the right and left kidneys in groups 1 and 2 (11.3 vs 10.8 and 11.9 vs 12.2 minutes, respectively). Two animals died of aspiration pneumonia (1) and wound dehiscence (1). In all 10 surviving animals no instance of urinary extravasation was noted. At 1-month followup regrowth of normal urothelium occurred with some scarring of the lamina propria or underlying smooth muscle. Adjacent renal parenchyma was replaced by fibrous scar. At 3 months the cryo-injured collecting system was completely healed with a fibrous scar. There were no appreciable histological differences between the kidneys with or without warm pelvicaliceal irrigation., Conclusions: Our data suggest that absent physical puncture injury of the collecting system with the cryoprobe tip the cryodamaged renal collecting system heals by secondary intention in a watertight manner. These data have clinical relevance for facilitating cryoablation of a small, localized, central renal tumor in proximity to the pelvicaliceal system.

Objectives: Laparoscopic renal cryoablation is a developmental minimally invasive nephron-sparing treatment alternative for highly select patients with small renal tumors. We present our evolving experience with this procedure., Methods: Thirty-two patients (34 tumors) with a mean tumor size of 2.3 cm on preoperative computed tomography underwent laparoscopic renal cryoablation. As dictated by the tumor location, cryoablation was performed by either the retroperitoneal (n = 22) or the transperitoneal (n = 10) laparoscopic approach using real-time ultrasound monitoring. A double freeze-thaw cycle was routinely performed., Results: The mean surgical time was 2.9 hours, cryoablation time 15.1 minutes, and blood loss 66.8 mL. For a mean intraoperative ultrasonographic tumor size of 2 cm, the mean cryolesion size was 3.2 cm. The hospital stay was less than 23 hours in 22 (69%) of 32 patients. Sequential magnetic resonance imaging scans demonstrated a gradual contraction in the mean diameter of the cryolesions. Of the 20 patients who underwent a 1-year follow-up magnetic resonance imaging scan, the cryoablated tumor was no longer visible in 5. Of note, 23 patients have now undergone a 3 to 6-month follow-up computed tomography-directed biopsy of the cryoablated tumor site; the biopsy was negative for cancer in all 23 patients. No evidence of local or port-site recurrence was found during a mean follow-up of 16.2 months., Conclusions: Critical long-term data regarding laparoscopic renal cryoablation, a developmental technique, are awaited. However, our initial experience is cautiously optimistic. Despite its significant potential for false-negative results, it is encouraging that the follow-up computed tomography-directed needle biopsies at 3 to 6 months were negative for cancer in 23 of 23 patients.

Objective: We describe the MR imaging findings of patients who underwent laparoscopic renal lesion cryoablation., Materials and Methods: Twenty-one patients (men, 11; women, 10; age range, 36-84 years; average age, 65.5 years; SD, 11.9) with 23 small renal masses (< or =4 cm) underwent laparoscopic renal lesion cryoablation. Twenty patients (22 masses) underwent follow-up MR imaging on the first day after surgery, 12 (13 masses) at 1 month, 16 (18 masses) at 3 months, 14 (15 masses) at 6 months, and 12 (12 masses) at 12 months. Three radiologists retrospectively reviewed MR images for the signal intensity, characteristics, and size of cryolesions. CT-guided needle biopsy was performed 6 months after cryoablation (18 patients) and no evidence of malignancy was discovered., Results: Including all lesions at all times on T1-weighted images, cryolesion signal intensity was isointense to renal parenchyma (47/76, 61.8%) or isointense with hyper- or hypointense foci (7/76, 9.2%). On T2-weighted images, almost all lesions (72/76, 94.7%) were isointense or hypointense, and there was a hypointense rim between the cryolesion and renal parenchyma in 38.2% of lesions (29/76). A thin peripheral rim of enhancement was noted in 19.7% (14/74) of lesions. Cryolesions decreased in size an average of 61.5% (SD, 22.82; n = 12) at 1 month, 78.7% (SD, 13.5; n = 17) at 3 months, 83.5% (SD, 24.3; n = 15) at 6 months, and 94.2% (SD, 8.1; n = 11) at 1 year after cryoablation (one patient was not scanned 1 day after cryoablation and was not included in our calculations)., Conclusion: After renal cryoablation, MR imaging revealed common signal characteristics such as low-signal-intensity rims on T2-weighted images, enhancement patterns such as thin peripheral rims, and interval size changes.

Objectives: To present the technique and short-term results of retroperitoneal laparoscopic renal cryoablation., Methods: Ten patients underwent laparoscopic renal cryoablation of 11 exophytic renal tumors ranging in size from 1.5 to 3 cm identified on computed tomography. Tumors were located at the upper (3), middle (5), or lower (3) pole of the kidney. Three patients had a solitary kidney. A 3-port retroperitoneal laparoscopic approach was used to create renal cryolesions. Puncture cryoablation was performed with a 4.8-mm cryoprobe. Real-time, endoscopic, steerable, color Doppler ultrasound was used to monitor the evolving cryolesion. All patients have completed a minimum follow-up of 3 months (mean 5.5, range 3 to 9)., Results: Cryoablation was technically successful in all 10 patients (11 tumors). Under ultrasound guidance, the ice ball was intentionally created up to 1 cm beyond the tumor edge with the aim of achieving negative margins. Mean surgical time was 2.4 hours, cryoablation (double freeze-thaw) time 12.9 minutes, cryoprobe tip temperature -186 degrees C, and blood loss 75 mL. Systemic temperature remained unaltered. Hospital stay was less than 23 hours in 9 of 10 patients. Follow-up magnetic resonance imaging at 1 day and 1, 2, and 3 months identified the punched-out, nonenhancing, spontaneously resorbing, renal cryolesion. Follow-up biopsies of the cryoablated tumor site were negative for cancer in the 3 patients who have undergone the biopsy., Conclusions: The initial series of laparoscopic renal cryoablation is presented. The retroperitoneoscopic approach, by avoiding the peritoneal cavity, minimizes the chances of the bowel coming in contact with the evolving cryolesion, and the potential sequelae thereof. Laparoscopic renal cryoablation is currently developmental and long-term data are awaited. Nevertheless, it is potentially an attractive addition to available nephron-sparing surgical techniques.