Initial experience with laparoscopically assisted percutaneous cryotherapy of renal tumors

BACKGROUND AND PURPOSE: Laparoscopic renal cryoablation is a feasible therapeutic option for small renal tumors. Advances in cryoablation technology have produced smaller cryoprobes. We review our initial experience with laparoscopic cryoablation utilizing 17-gauge cryoneedles. PATIENTS AND METHODS: Four patients aged 21 to 78 years underwent laparoscopy-assisted percutaneous cryotherapy between May 2003 and March 2004. The tumor size ranged from 1.5 to 2.5 cm. The procedure involved transperitoneal exposure of the tumor utilizing three 5- or 10-mm ports. The cryoprobes were placed percutaneously, without the need for tract dilation. Two freeze-thaw cycles were performed with cooling to below -70 degrees C. RESULTS: In all patients, the procedure was completed without complication. The mean operative time was 125 minutes. The mean blood loss was 29 mL. No perioperative complications occurred. In follow-up, one patient with a tumor suspected of being renal-cell carcinoma demonstrated residual enhancement and underwent percutaneous radiofrequency ablation. CONCLUSIONS: Laparoscopy-assisted percutaneous cryotherapy is a feasible treatment option in patients with small renal tumors. Laparoscopy allows mobilization of both anterior and posterior tumors. Direct viewing of the mass may facilitate accurate placement of the cryoneedles. The small size of the cryoneedles minimizes bleeding at the entry site.     

Computerized tomography guided percutaneous renal cryoablation with the patient under conscious sedation: initial clinical experience

PURPOSE: We report on our initial clinical experience with CT guided percutaneous renal cryoablation. MATERIALS AND METHODS: CT guided percutaneous renal cryoablation was performed on 27 tumors using conscious sedation in 20 patients. Eligible patients had tumors of 5 cm or less and were poor surgical candidates or otherwise warranted nephron sparing treatment. Tumors were classified as central or noncentral depending on their relationship to the renal sinus fat. During cryoablation intraoperative active ice ball formation was monitored with real-time CT imaging to ensure adequate tumor coverage. Postoperative followup imaging was obtained at regular intervals. RESULTS: Our method appears technically feasible as of the 27 cryoablations performed, only 1 complication occurred requiring blood transfusion in a patient with a large, centrally located tumor. To date we have 16 tumors in 12 patients with imaging followup of 1 month or more (mean followup 5.9 months). Mean baseline tumor size in this group was 2.5 cm with 11 small (3 cm or less) and 5 large (more than 3 cm) tumors. Of the tumors 5 were centrally located and 11 were noncentrally located. Preliminary data suggest that of the 16 cryoablated tumors 15 showed no signs of enhancement on followup. CONCLUSIONS: CT guided percutaneous renal cryoablation appears to be a feasible treatment option for small, noncentrally located renal tumors. While early results appear promising, longer followup is needed to more clearly define the role of this treatment method.     

Percutaneous renal tumor cryoablation with magnetic resonance imaging guidance

PURPOSE: Cryoablation of small renal tumors has been performed mainly via the laparoscopic or open approach. This study was done to assess the feasibility and safety of performing percutaneous renal tumor cryoablation using interventional magnetic resonance imaging (MRI) for monitoring. MATERIALS AND METHODS: Patients with radiography documented small renal tumors 4 cm or less in diameter were offered percutaneous renal tumor cryoablation performed in an interventional MRI unit. Patients received general anesthesia or intravenous sedation and were placed into the interventional MRI unit. Under MRI guidance a 2 or 3 mm cryoprobe was advanced into the renal mass and the mass was subjected to 3 freeze-thaw cycles at -80 to 70C. Patients were hospitalized overnight for observation. Followup imaging with MRI or computerized tomography and physical examinations were done at 1 week, and 1, 3, 6 and 12 months. RESULTS: Ten men and 10 women 49 to 76 years old (mean age 58) with a total of 22 tumors have been treated, including 1 with bilateral lesions and another with 2 tumors in 1 kidney. Mean tumor diameter was 3 cm. (range 1.8 to 7.0). Two patients with a mass exceeding study entry criteria (5 and 7 cm, respectively) who were not open surgery candidates were treated on a compassionate basis. Average treatment time was 97 minutes (range 56 to 172). To date 1 patient has had evidence of persistent tumor on followup imaging and required re-treatment. The only complication was a superficial wound abscess. Mean followup was 9.1 months (range 3 to 14) with no radiographic evidence of disease recurrence or new tumor development. CONCLUSIONS: In this small series of patients percutaneous renal tumor cryoablation was technically feasible with minimal morbidity. At limited followup there appears to be no radiological evidence of new tumor development. Percutaneous cryoablation may prove to be an additional treatment option for small renal tumors.     

Percutaneous cryoablation of renal cell carcinoma guided by horizontal open magnetic resonance imaging

BACKGROUND: Cryoablation is a treatment option for some patients with small exophytic lesions of the kidney. The purpose of this study is to determine the feasibility, safety, and intermediate-term treatment outcome of percutaneous cryoablation of renal cell carcinoma guided by horizontal open magnetic resonance imaging (MRI). METHODS: We prospectively used cryoablation to treat 13 patients with radiographically confirmed enhancing small, solid renal tumors (< or =4.8 cm). An argon gas-based cryoablation system was used. One to four cryoprobes with 2 or 3-mm diameters were placed percutaneously into the tumor under local anaesthesia and MRI guidance. Ice ball dimensions were monitored by 2-D MR images. Double freeze-thaw cycles were conducted throughout the procedure. After successful cryoablation, patients were followed on a regular basis to evaluate the treatment's clinical outcome. RESULTS: Median follow up from time of procedure is 35 months (range, 28-42). In all cases the entire procedure was accomplished without significant morbidity or complications. A mild retroperitoneal hematoma, which subsided spontaneously, was noted in one patient. Follow-up dynamic computed tomography (CT) at 3 months after operation confirmed the absence of enhancement in resolved tumor masses for 11 of 13 cases. None of these 11 patients had clinical evidence of recurrent disease at last follow up. The remaining two patients had lesions with some enhanced areas. Subsequent partial nephrectomy histologically confirmed the presence of vital tumor in, respectively, the center and the periphery of the residual masses. One of these patients developed multiple lung and ipsilateral adrenal metastases 13 months after surgical resection. CONCLUSIONS: Percutaneous cryoablation of small renal cell carcinomas under horizontal open MRI guidance appears to be safe and feasible. An intermediate-term follow up continues to demonstrate efficacy in most patients; however, a few patients experience incomplete ablation with risk of treatment failure. The ideal candidates for this procedure still need to be determined in longer follow up with diligent observation.     

Percutaneous renal cryoablation of renal tumors in patients with von Hippel-Lindau disease

PURPOSE: We determine the feasibility and safety of performing percutaneous cryoablation of renal tumors in patients with von Hippel-Lindau disease. MATERIALS AND METHODS: We selected 2 men and 2 women with von Hippel-Lindau disease and radiographic determined solid renal tumors were selected to undergo percutaneous cryoablation. All patients underwent standard preoperative evaluation. An interventional magnetic resonance imaging unit was used for probe guidance and ice ball monitoring. The cryoablation procedure was performed with a 2 or 3 mm. cryoprobe using a pressurized argon gas system for ice ball formation. The patients were hospitalized overnight for observation and discharged home the following day. A followup computerized tomogram or magnetic resonance imaging scan was performed at 1 week, 1, 3, 6 and 12 months and every 6 months thereafter, along with physical examination, urinalysis, serum blood urea nitrogen and creatinine. RESULTS: A total of 5 tumors were treated ranging from 2.8 to 5.0 cm. in diameter. All patients underwent the procedure without difficulty with 2 requiring re-treatment due to residual tumor for a total of 7 treatments. At followup from 2 to 23 months there has been no radiographic evidence of recurrence at the cryoablated areas. CONCLUSIONS: Percutaneous cryoablation of renal tumors in patients with von Hippel-Lindau disease proved to be successful in this initial series. Although 2 patients had residual tumor after the initial cryoablation procedure re-treatment was performed with no adverse sequela. This minimally invasive therapy may allow patients with von Hippel-Lindau disease to avoid the necessity of multiple open surgical procedures.     

Percutaneous computerized tomography guided renal cryoablation using local anesthesia: pain assessment

PURPOSE: The administration of intravenous sedation during prone computerized tomography guided, percutaneous procedures has the potential for complications. We assessed the pain associated with computerized tomography guided, percutaneous renal cryoablation using straight local anesthesia. MATERIALS AND METHODS: Patients were treated with cryoablation probes inserted into the renal tumor under computerized tomography guidance with local anesthesia. Patients were asked to rate the pain experienced during needle placement and cryoablation using a visual 10-degree pain score scale. Sedation was given when pain was greater than 7 or when requested by the patient. Parameters assessed were cardiopulmonary complications, the need for intravenous supplementation, the pain score during the procedure and the postoperative score. RESULTS: A total of 25 patients (30 tumors) underwent a total of 26 cryoablation sessions with only local anesthesia. Mean patient age +/- SD was 67 +/- 13 years (range 33 to 88). Average tumor and ice ball size was 2.1 +/- 0.7 (range 1.1 to 4.3) and 4.1 +/- 1.0 cm (range 2.6 to 5.9), respectively. The mean dose of 1% lidocaine was 43.89 +/- 24.97 ml (range 10 to 110). All procedures were completed in an average of 68.78 +/- 20.7 minutes (range 40 to 120). Vital signs were not significantly changed during the procedure. Successful completion of percutaneous computerized tomography guided cryoablation using local anesthesia was accomplished in 22 of the 26 sessions (84.62%) without sedation. Four patients required intravenous supplementation. CONCLUSIONS: Percutaneous computerized tomography guided cryoablation for renal tumors can be performed using local anesthesia with minimal discomfort in most patients.     

Results of computerized tomography guided percutaneous ablation of renal masses with nondiagnostic pre-ablation pathological findings

PURPOSE: Ablative therapy for renal masses has been criticized because the entire tumor cannot be evaluated pathologically after the procedure. Diagnosis depends on imaging findings and the results of percutaneous needle biopsies, which may be nondiagnostic in up to 21% of cases. We determined outcomes in patients undergoing ablation who had nondiagnostic biopsies at the time of the procedure. MATERIALS AND METHODS: A total of 79 patients (88 renal masses) underwent percutaneous computerized tomography guided biopsy and ablation of a renal mass under conscious sedation. Patients with nondiagnostic biopsies were identified and the medical records were reviewed retrospectively. All patients had an enhancing renal mass on preoperative computerized tomography or magnetic resonance imaging and all underwent postoperative contrast imaging to evaluate persistent viable tumor. RESULTS: A total of 19 patients (20 tumors) with nondiagnostic percutaneous biopsy (22.7% or 20 of 88) were included in the study. No serious complications occurred. Tumors were treated with frequency ablation (12) or cryoablation (7). In 17 patients (89.5%) post-procedure imaging confirmed the absence of contrast enhancement at a median followup of 27.3 months (range 3 weeks to 56 months). In 2 cases (10.5%) post-procedure imaging showed a residual renal mass or recurrence with enhancement, suggesting that the original percutaneous biopsy result was false negative. In 1 patient residual tumor was identified on initial post-ablation imaging and the patient underwent laparoscopic partial nephrectomy. In another patient recurrence was diagnosed 30 months after ablation and the patient underwent laparoscopic radical nephrectomy. Although there was a nondiagnostic percutaneous biopsy in each case, pathological findings in the subsequent surgical specimen confirmed renal cell carcinoma. CONCLUSIONS: Nondiagnostic percutaneous biopsy at renal tumor ablation does not obviate the need for standard post-procedure imaging followup. Of patients with nondiagnostic biopsies in this series 10.5% still harbored viable renal cell carcinoma after percutaneous ablation.     

Percutaneous computerized tomography guided cryoablation for localized renal cell carcinoma: factors influencing success

PURPOSE: We evaluated the factors that influenced the initial success rate and complication rate of percutaneous computerized tomography guided cryoablation of localized renal cell carcinoma of clinical stage T1N0M0. MATERIALS AND METHODS: A total of 21 patients with a mean age of 71.5 years and a pathological diagnosis of renal cell carcinoma were treated with percutaneous computerized tomography guided cryoablation under conscious sedation on an outpatient basis. We retrospectively reviewed clinical data, tumor characteristics, techniques and results. Tumors with complete loss of contrast enhancement were considered successfully treated. RESULTS: A total of 21 patients with 23 tumors underwent 25 cryoablation sessions. The mean intraoperative computerized tomography scan tumor size was 2.1 cm (range 0.5 to 4.3) and the mean ice ball size was 4.1 cm (range 2.2 to 7.2). Of the patients 82.6% (19 of 23) had a single treatment. Patients were followed with postoperative scans of 4.6 to 18.3 months (mean 12.3). There were 2 recurrences. The rate of successful complete tumor ablation was influenced by various factors. Tumor location and size were the major determinants for achieving tumor eradication. CONCLUSIONS: Percutaneous renal cryoablation using computerized tomography imaging proved to be a successful technique for guiding probe placement and monitoring ice ball formation. Patient selection based on tumor size and location may aid in improved outcomes. Further study and followup are necessary to determine long-term oncological efficacy.     

Pilot experience with real-time ultrasound guided percutaneous renal mass cryoablation

PURPOSE: We describe our pilot experience with percutaneous cryoablation of renal masses using real-time sonography. MATERIALS AND METHODS: Three patients presented with 4 renal masses in 4 kidneys, which enhanced with contrast administration by computerized tomography or magnetic resonance imaging criteria. Renal neoplasm cryoablation was performed using general anesthesia with 17 gauge cryoneedles percutaneously placed into the renal tumor under real-time sonographic guidance. Followup cross-sectional imaging was performed 6 to 7 weeks following cryoablation in all patients. RESULTS: No perioperative complications were noted. All patients were discharged home within 24 hours of the procedure and postoperative pain was controlled with oral nonnarcotic medications. Followup cross-sectional imaging indicated that the lesions shrank an average 63% +/- 15% from initial pretreatment volume. Importantly none of the lesions showed contrast enhancement by computerized tomography or magnetic resonance imaging criteria. CONCLUSIONS: Our initial experience shows that percutaneous, sonographically guided renal neoplasm cryoablation can be a safe method for treating renal masses.     

磁共振导航经皮穿刺肝癌冷冻消融治疗27例

目的探讨在开放式磁共振（MRI）监视下采用经皮穿刺方法进行肝癌的冷冻消融治疗的可行性、疗效和安全性。方法2008年1～9月,对27例原发性肝癌在MRI引导下行经皮肝穿刺行氩氦刀治疗2个冷冻、解冻程序,MRI显示冰球扩展并包裹整个肿瘤。冷冻治疗后第10天联合肝动脉灌注化疗栓塞（TACE）5例。结果MRI引导下经皮穿刺冷冻治疗均成功,26例（96.3%）显示冰球扩展并包裹整个肿瘤,呈现边缘清晰的信号暗区,1例冰球不能包裹整个肿瘤。术后随访1～12个月,平均3.5月,甲胎蛋白（AFP）值下降至正常14例（51.9%）,AFP持续升高1例,先降复又升高12例。进行1次以上影像学复查肿瘤完全坏死或无明确存活病灶14例（51.9%）,肿瘤不完全坏死或有存活病灶13例（48.1%）。无严重并发症。结论MRI引导下经皮穿刺的肝脏肿瘤冷冻消融治疗是可行和安全的,疗效确切。     

PERCUTANEOUS CRYOABLATION OF PORCINE KIDNEYS WITH MAGNETIC RESONANCE IMAGING MONITORING

PURPOSE: We determined the feasibility of a percutaneous approach using magnetic resonance imaging (MRI) for creating cryoablation lesions in the porcine kidney. METHODS AND METHODS: Three domestic swine underwent renal cryoablation under MRI guidance with a total of 6 cryoablation lesions created in 5 kidneys. A 3 mm. cryoprobe was placed under MRI guidance using an interventional MRI unit. With a pressurized argon gas cooling unit the cryoablation lesion was created and monitored by MRI. Gross and histological examination of the kidneys was performed 1 week after the procedure. RESULTS: All animals survived the procedure without difficulty. A total of 6 cryoablation lesions were produced in 5 kidneys. The lesions were 1.9 x 1.3 to 3.9 x 1.9 cm. on MRI. Histological examination 1 week after treatment showed that the lesions were 1.7 x 1.0 to 3.2 x 1.2 cm. There was an area of coagulation necrosis surrounded by a transition zone of inflammatory reaction a mean of 0.5 cm. in diameter with each lesion. CONCLUSIONS: Percutaneous renal cryoablation using MRI imaging proved to be a successful technique for guiding probe placement and monitoring ice ball formation. Because MRI allows imaging in 3 planes, it may be useful for cryoablation of intraparenchymatous tumors.     

后腹腔镜下冷冻消融治疗小肾肿瘤的初步报告

目的 探讨后腹腔镜下冷冻消融治疗小肾肿瘤的临床疗效.方法 肾肿瘤患者10例,共11个肿瘤.肿瘤位于左肾3例、右肾6例、双肾1例;肾上极2例、中极6例、下极3例.均经CT或MRI检查证实:肿瘤直径平均2.8(1.5～4.0)cm,远离集合系统,无远处转移.临床分期均为T1aN0M0.实验室检查Hb(137±21)g/L、红细胞沉降率(ESR)(27±12)mm/1 h、SCr(92±41)μmol/L、GFR(42±10)ml/min.均采用后腹腔镜下冷冻消融治疗.术中常规行穿刺病理检查. 结果 10例患者手术均成功,平均手术时间(101±31)min,平均出血量(42±21)ml.未发生腹腔镜手术相关并发症.术后平均住院(4±2)d.术后Hb(129±18)g/L,ESR(31±14)mm/1 h,SCr(95±39)μmol/L,患肾GFR(40±11)ml/min,与术前比较差异均无统计学意义(P＞0.05).病理检查,11个肿瘤中透明细胞癌8个、乳头状肾细胞癌2个、血管平滑肌脂肪瘤1个.10例平均随访16(6～21)个月.术后第1、3和6个月复查MRI,肿瘤冷冻区域呈梗死、无信号增强、逐渐消散等演变过程.术后6个月肿瘤冷冻区域活检1例阴性.无局部复发或远处转移病例.结论 后腹腔镜下冷冻消融治疗小肾肿瘤安全有效,远期疗效尚需进一步随访观察.     

Pain after percutaneous radiofrequency ablation of renal tumors

BACKGROUND AND PURPOSE: Most patients have minimal pain after percutaneous radiofrequency ablation (RFA) of a renal tumor. However, anecdotally, there is some variation in the amount of patient discomfort. Our goal was to identify relevant patient factors and characteristics of their renal tumors that may influence pain after percutaneous RF ablation. PATIENTS AND METHODS: We performed a retrospective chart review of 59 sequential patients who received percutaneous RFA between 2001 and 2005 at a single institution. Data on patient age, sex, body mass index (BMI), and narcotic administration in the periprocedural period were available for 46 patients. Preoperative imaging (CT or MRI) was reviewed to determine tumor size and location, as well as the shortest distance of the mass to the body-wall musculature. RESULTS: The distance from the renal mass to the body-wall musculature was significantly correlated with the total narcotics received in the periprocedural period. This measured distance did not correlate with the patient's BMI. No other relations between patient factors or tumor characteristics and peri-procedural narcotic usage were identified. CONCLUSION: Patients whose tumors lie close to their body-wall musculature have greater narcotic requirements in the periprocedural period. Knowledge of this correlation should result in better patient counseling and help anticipate periprocedural analgesia requirements.     

Retroperitoneoscopy-assisted cryoablation of renal tumors using multiple 1.5 mm ultrathin cryoprobes: a preliminary report

OBJECTIVES: Laparoscopic cryoablation has recently been proposed as a minimally invasive nephron-sparing treatment for selected patients. We report on our experience with a retroperitoneoscopic technique using multiple ultrathin cryoprobes. METHODS: Seven patients underwent retroperitoneoscopic renal cryoablation for solid renal masses. Mean tumor size on the CT scan was 2.6 (1.5-3.5) cm. A double freeze-thaw cycle of renal cryoablation was performed under real-time ultrasound monitoring using a total of six 1.5-mm cryoprobes simultaneously. RESULTS: Cryoablation was technically successful in all patients without any need for conversion. Mean duration of surgery was 161 (130-195) minutes and mean blood loss was 107 (50-250) ml. Perioperative biopsy of the tumor confirmed renal cell carcinoma in four patients and angiomyolipoma in two patients; it was inconclusive in one case. Mean follow-up for 13.6 (4-22) months showed no evidence of residual tumor or recurrence. CONCLUSIONS: Retroperitoneoscopy-assisted cryosurgical ablation using multiple ultrathin 1.5-mm cryoprobes is a minimally invasive treatment that is suitable to treat small renal tumors.     

Percutaneous image-guided cryoablation with temporary balloon occlusion of the renal artery for the treatment of central renal tumors

PurposeThe purpose of this study was to report the technical feasibility and outcomes of percutaneous image-guided cryoablation with temporary balloon occlusion of the renal artery for the treatment of central renal tumors.Materials and methodsAll consecutive patients with central renal tumors treated with cryoablation and temporary renal artery occlusion from January 2017 to October 2021 were retrospectively included. Patient demographics, tumor's characteristics, procedural data, technical success, primary and secondary clinical efficacy, complications (according to Cardiovascular and Interventional Radiology Society of Europe [CIRSE] classification) and follow-up were investigated.ResultsA total of 14 patients (8 men, 6 women; mean age 72.4 years ± 21.4 [SD] years; age range: 42–93 years) with 14 central renal tumors (median size, 32 mm; IQR: 23.5, 39.5 mm; range: 13–50 mm) were treated with percutaneous image-guided cryoablation and temporary balloon occlusion of the renal artery. Technical success was 13/14 (93%), with 1/14 (7%) failure of vascular access. A median of 4 cryoprobes (IQR: 3, 4.75) were inserted and protective hydrodissection was performed in 11/14 (79%) patients. Median time to perform cryoprobes insertion, hydrodissection and vascular access was 26.5 min (IQR: 18, 35 min), 10 min (IQR: 10, 17 min) and 30 min (IQR: 20, 45 min) respectively. Median duration of the whole intervention was 150 min (IQR: 129, 180 min; range: 100–270 min). Median hospital stay was 2.5 days (IQR: 2, 4 days; range: 2–14 days). Major complications occurred in 3/14 (21%) patients. Primary efficacy rate was 93% (13/14 patients). Median oncological follow-up was 25 months (IQR: 11, 33 months; range: 6–39 months). One patient experienced renal tumor recurrence at 14-months of follow-up, which was successfully treated with repeat cryoablation.ConclusionPercutaneous image-guided cryoablation of renal tumors with temporary balloon occlusion of the renal artery is technically feasible, with a high technical success rate and paths the way for percutaneous treatment of central renal tumors.     

Ultrasound-guided percutaneous ablation of a renal mass in a renal allograft

A 50-year-old man underwent magnetic resonance imaging and was found to have an incidental 3.2-cm mass in a renal allograft. Because of the multiple comorbidities associated with renal allograft patients, a minimally invasive option such as percutaneous ablation should be considered. The patient underwent percutaneous ultrasound-guided cryoablation. The final histopathologic examination of the needle biopsy was consistent with an oncocytic neoplasm. The 9-month follow-up contrast-enhanced magnetic resonance imaging scan showed no residual tumor. Long-term follow-up and greater clinical experience are still necessary to confirm the efficacy of cryoablation for allograft lesions.     

Defining the complications of cryoablation and radio frequency ablation of small renal tumors: a multi-institutional review

PURPOSE: Ablative treatments (cryoablation or radio frequency ablation) for renal cell carcinoma aim to decrease morbidity by treating renal tumors in situ, eliminating the need for extirpation. These technologies have potential for complications previously unassociated with renal tumor treatment. We identified complications associated with percutaneous and laparoscopic ablative treatment of renal tumors. MATERIALS AND METHODS: Groups at medical centers with reported experience with ablation of renal tumors were invited to participate in this study. Each group submitted retrospective data regarding overall ablative treatment experience and associated complications. For each incident the nature of the complication, its associated morbidity, the necessity and nature of any subsequent interventions, and the final patient outcome were evaluated. Complications were divided into minor and major categories. Data were collected from groups at 4 institutions with a combined experience of 271 cases. Of these cases 139 were cryoablation and 133 were radio frequency ablation. There were 181 procedures performed percutaneously and 90 performed laparoscopically. RESULTS: A total of 30 complications occurred (11.1%) with 5 major (1.8%) and 25 minor (9.2%) complications, and 1 death (0.4%). Overall 26 of the 30 complications (86.7%) were directly attributable to the ablation procedure. The most common complication was pain or paraesthesia at the probe insertion site. CONCLUSIONS: Ablation technologies appear to have a low complication profile when used to treat small renal tumors. The majority of complications are minor and require observation only. Further study and followup are necessary to determine long-term oncological efficacy.     

Early experience with laparoscopic cryoablation in patients with small renal tumors and severe comorbidities

PURPOSE: To present our preliminary experience with laparoscopic renal cryoablation in patients with small renal tumors and severe comorbidities. PATIENTS AND METHODS: Eight patients with a mean age of 75.6 years (range 68-82 years) who had small (mean 2.6+/-0.7-cm; range 1.4-3.8-cm) peripheral renal cortical lesions and significant comorbidities underwent laparoscopic cryoablation with a 3-mm cryoprobe. None of the patients was considered a good candidate for extirpative surgery. Tumors were biopsied prior to cryoablation. Intraoperative laparoscopic ultrasonography was utilized to confirm the tumor and to monitor the biopsy and the cryoablation process. RESULTS: Most patients had right-sided tumors, although there were no significant differences in the approach or outcome on this basis. Seven patients had intraoperative biopsies, and in all cases, good tissue samples were obtained. There were no intraoperative or postoperative complications. The average blood loss was 102.5+/-123.3 mL, and the mean operative time was 120+/-27.8 minutes. The mean hospital stay was 2.9+/-1.6 days. Postoperative imaging demonstrated defects consistent with ablation of the affected area; however, a residual nonenhancing mass defect usually was demonstrated. CONCLUSION: Laparoscopic cryoablation appears to be safe for the treatment of solid or complex renal masses in elderly patients with severe comorbidities. Further studies are necessary to determine the long-term efficacy before this modality can be considered an acceptable curative treatment for small renal cortical tumors.     

Cryoablation of renal tumours in patients with solitary kidneys

OBJECTIVE: To investigate the use of cryoablation for small renal tumours (相似文献   

Laparoscopic cryoablation under sonographic guidance for the treatment of small renal tumors

PURPOSE: To evaluate the efficacy of ultrasound-guided laparoscopic cryoablation of small renal tumors. PATIENTS AND METHODS: Eleven men and five women with solid renal tumors (mean size 2.6 cm) were treated using laparoscopically monitored cryoablation between October 2000 and October 2002. Nine tumors were left sided and seven right. Ten patients were treated retroperitoneoscopically and six transperitoneally. A double-freeze/active-thaw technique was utilized with two 10-minute freeze cycles. RESULTS: The mean operating time was 188 minutes. There was one open conversion for failure to progress. The mean blood loss was 40 mL. Tumor biopsy demonstrated five renal-cell carcinomas, two oncocytomas, and lesions that either were benign or were not biopsied. The mean hospital stay was 1.9 days with a median stay of 1 day. With a mean follow-up of 9.6 months, all tumors remain nonenhancing and are stable or smaller than the original lesion. Two patients have died of unrelated causes and without evidence of disease. CONCLUSIONS: This series of patients adds to the growing body of literature suggesting that cryoablation is a well-tolerated method for treating small renal tumors. Longer follow-up is required to fully define its place in the therapeutic armamentarium.