Cryoablation Of Small Renal Masses Research Articles

Preoperative lipiodol marking and its role on survival and complication rates of CT-guided cryoablation for small renal masses

BackgroundPartial nephrectomy for small renal masses (SRM) may be useful for preserving renal function, but is technically more difficult than radical nephrectomy. Cryoablation may be performed under local anesthesia. The objective of the present study is to assess the safety and therapeutic efficacy of cryoablation with lipiodol marking for SRM.MethodsCryoablation therapy was performed on 42 patients under local anesthesia. Their median age was 74 years (31–91). The median tumor diameter was 21 mm (10–42). Responses to the treatment were evaluated using modified Response Evaluation Criteria in Solid Tumors (mRECIST) by contrast-enhanced CT. In six patients (14.3%) for whom it was not possible to use contrast medium, plain CT findings were assessed according to Response Evaluation Criteria in Solid Tumors (RECIST).ResultsTwenty-nine (69%) and five (12%) patients achieved complete responses (CR) and partial responses (PR), respectively, while four (10%) and four (10%) patients each had stable disease (SD) and progressive disease (PD) after the first course of therapy. A second course of cryoablation therapy with lipiodol marking was performed on three out of four patients with PD after the first course of therapy, and resulted in a total of 32 patients achieving CR (76%). Four (36.4%) out of 11 patients for whom lipiodol marking was not conducted had PD, whereas none of the 31 patients for whom lipiodol marking was conducted had PD. All grade complications were reported in 11 (24.4%) patients while grade 3 in two (4.4%) patients. 11 (24.4%) A significant difference was observed in postoperative hemorrhagic events in all grades (18% in patients undergoing cryoablation without lipiodol marking vs. 0% in patients undergoing cryoablation without lipiodol marking).ConclusionsAlthough further studies involving more patients are needed in order to evaluate long-term results, cryoablation therapy appears to be a useful treatment option for SRM. Preoperative marking with lipiodol was helpful for improving complication and survival rates with cryoablation.

P146 - Preoperative lipiodol marking improved safety and success rate on CT-guided cryoablation for small renal masses

P146 - Preoperative lipiodol marking improved safety and success rate on CT-guided cryoablation for small renal masses

Preoperative Aspects and Dimensions Used for Anatomical Score Predicts Treatment Failures in Laparoscopic Cryoablation of Small Renal Masses.

To determine the potential of the preoperative aspects and dimensions used for anatomical (PADUA) classification score as a predictive tool in relation to residual unablated tumor and disease-free survival (DFS) following laparoscopy-assisted cryoablation (LCA) of small renal masses. A multi-institutional cohort of 212 patients with biopsy-verified T1N0M0 renal malignancies treated with LCA between August 2005 and September 2014 were retrospectively investigated with respect to oncologic outcomes. The preoperative PADUA score was found to be low (6-7 points) in 70 patients (33%), moderate (8-9 points) in 86 patients (40.6%), and high (10-14 points) in 56 patients (26.4%). The mean PADUA score was significantly higher in cases (n = 11) with residual unablated tumor (10.4 vs 8.1, p < 0.001) and in cases (n = 8) with local tumor recurrence (9.8 vs 8.1, p < 0.001) at a mean follow-up of 37 (95% confidence interval: 34-40) months. The estimated 2-, 3-, and 5-year DFS for patients with a moderate PADUA score was 96%, 94%, and 94% compared with 95%, 87%, and 81%, respectively, for patients with a high PADUA score (log-rank, p = 0.003). The PADUA score did not predict overall survival. The PADUA score significantly predicts residual unablated tumor and DFS following LCA. Further studies are needed to validate the efficacy of the PADUA score in relation to oncologic outcomes following ablative procedures.

Percutaneous image-guided cryoablation of small renal masses.

Renal cell carcinoma is a common malignancy with increasing incidence due to the incidental detection of non-symptomatic small renal masses on imaging. Management of these small tumors has evolved toward minimally invasive nephron-sparing techniques which include partial nephrectomy and image-guided ablation. Cryoablation and radiofrequency ablation are the most utilized ablation modalities with the former more suited for larger and central renal masses due to intra-procedural visualization of the ablation zone and reduced pelvicalyceal injury. In this article, we review the epidemiology and natural history of renal cell carcinoma, the role of biopsy, and the management options available-surgery, image-guided ablation, and active surveillance-with a focus on cryoablation. The clinical outcomes of the longer term maturing cryoablation data are discussed with reference to partial nephrectomy and radiofrequency ablation. Image-guided ablation has often been the management choice in patients deemed unfit for surgery; however, growing evidence from published series demonstrates image-guided ablation as a sound alternative treatment with equivalent oncological outcomes and minimal patient impact.

Clinical Outcomes of Patients With Nondiagnostic Biopsy During Cryoablation of Small Renal Masses

To compare the outcomes of patients with biopsy-proven renal cell carcinoma (RCC), benign tumors (BTs), and nondiagnostic (ND) biopsies after renal cryoablation (RC). We retrospectively reviewed medical records of 114 patients who underwent RC between 2003 and 2013. Patients were stratified according to biopsy histopathology results-RCC, BT, and ND biopsy. We recorded patient demographics and tumor features and examined oncologic outcomes among the 3 groups. RC was performed in 114 patients with 117 tumors. Seventy-two tumors (61.5%) were RCC, 18 (15.4%) were BTs (oncocytoma or angiomyolipoma), and 27 (23.1%) were ND. Patient characteristics and tumor features were similar among the 3 groups. The median follow-up was 26.5, 26.0, and 22.0 months in the RCC, BT, and ND biopsy groups, respectively (P = .18). Residual disease occurred in the RCC (1.4%) and ND biopsy (7.4%) groups, but not in the BT group (P = .19). All 9 patients (12.5%) who developed recurrent disease had biopsy-proven RCC. The 2- and 5-year recurrence-free survival rates (RFS) for patients with biopsy-proven RCC were 90.2% and 81.2%, respectively. Because no patient in the BT and ND biopsy groups had a recurrence, their RFS was 100%. No patient with a BT or ND biopsy developed a local recurrence with short-term follow-up, whereas a recurrence developed in 12.5% of biopsy-proven RCC tumors. RFS for patients with biopsy-proven RCC was worse than the other 2 biopsy groups, although not statistically significant. Long-term follow-up in a larger cohort of patients is needed to further evaluate these preliminary findings.

Abstract No. 411 - Surviving the interventional radiology ice-bucket challenge: percutaneous cryoablation of renal masses in difficult anatomic locations

Renal masses in difficult anatomic locations can often be safely and appropriately treated with percutaneous image-guided cryoablation. The purpose of this exhibit is to describe and demonstrate adjunctive techniques that improve safety and technical success rates of percutaneous cryoablation of renal masses in difficult anatomic locations. Management strategies for the treatment of small renal masses include active surveillance, percutaneous ablation, or nephron-sparing surgery. The decision is made based on age of patient, medical history, surgical comorbidities, mass size and location, rate of growth, and patient preference. Percutaneous image-guided cryoablation is a well-accepted, minimally invasive therapy to treat small renal masses, particularly in patients who are poor surgical candidates due to multiple comorbidities, multiple tumors, or renal failure. Lesions typically considered more difficult to ablate include central lesions, size larger than 3 centimeters, upper pole location, endophytic, and adjacent to ureter, colon, or other organs. Some renal lesion locations have been classically described as more difficult to treat with percutaneous cryoablation due to risk of damaging adjacent critical structures, such as the ureter, renal pelvis, or adjacent bowel. Retrograde pyeloperfusion, hydrodissection, and angioplasty balloon interposition are three techniques that can be used to safely perform cryoablation in these difficult anatomic locations. In addition, choosing a patient position on the procedure table to create the safest treatment window is critical. These techniques can be used individually or in combination to improve safety when ablating renal masses in challenging anatomic locations. Maximizing patient positioning, retrograde pyeloperfusion, hydrodissection, and angioplasty balloon interposition are critical adjunctive techniques that can be used to improve safety when performing percutaneous image-guided cryoablation of small renal masses in difficult anatomic locations.

1:27 PM, Abstract No. 269 - Safety and efficacy of renal cryoablation for small renal masses: midterm follow-up

database, all patients with stage T1aN0M0 RCC (r4cm) diagnosed in 2004 to 2011 were identified. Sociodemographic trends in use of surgery vs. TA were evaluated by chi-square and logistic regression. Overall survival (OS) was estimated using Kaplan-Meier from the time of diagnosis. Difference in utilization rate of TA in 2004-2007 vs. 2008-2011 was observed. Results: Of 28351 patients with T1a lesion, 2133 (7.5%) did not receive curative therapy. Of 26218 patients who received curative therapy, the majority underwent surgical resection: 24992 (95.3%) surgical resection, 671(2.6%) CRA, 553(2.1%) (po0.001). While mean overall survival was similar between the surgery (81.1 months) and TA (81.0 months) group (p1⁄40.612). Those who did not receive curative therapy had a significantly shorter mean OS (70.4 mo; po0.001) when compared to curative group as a whole. Furthermore, mean OS for TA group was also significantly prolonged compared to no curative therapy group (po0.001). Being unmarried, Z65 years of age, being insured, living in metropolitan areas, in Pacific Coast region, and residing in areas with higher median family income demonstrated higher likelihoods of receiving TA when compared to surgery (po0.001). There was a significant increase in the rate of use of TA compared to surgery in more recent years (3.2% in 2004-2007 vs. 5.3% in 2008-2011 (po0.001)). Older age, being unmarried, living in rural areas with lower median family income and lower educational status were found to be predictor of not receiving therapy. Conclusion: There was significant disparity in the management of T1a RCC lesions, in part affected by patient’s sociodemographic determinants. In addition, there was significant underutilization of less invasive thermal ablation which demonstrated similar survivorship compared to surgery and significantly prolonged survival compared to no therapy.

Contrast-enhanced ultrasound (CEUS): an excellent tool in the follow-up of small renal masses treated with cryoablation.

Strict imaging follow-up is mandatory after cryoablation of small renal masses (SRMs). Although it uses ionizing radiation and nephrotoxic iodinated contrast, computed tomography (CT) is still the gold standard test. Contrast-enhanced ultrasound (CEUS) is a novel technique that informs in real time about renal perfusion avoiding radiation and nephrotoxicity. The objective of this study is to compare outcomes between CEUS and CT in the follow-up of SRMs treated with cryoablation, as well as to assess degree of agreement between them. This is a prospective observational study (May 2012 to December 2013) comparing CEUS and CT in 16 patients with SRMs cryoablated. The on-going protocol of the study includes a CT and CEUS 3 months after treatment and then every 6 months during 5 years. Local relapse was defined as the presence of contrast enhancement in the mass. All the CEUS were performed by a single experienced observer (E.S.). Degree of agreement was measured with kappa index. CEUS detected contrast enhancement in three patients (3/16, 18.8%) and CT in two patients (2/16, 12.5%). Degree of agreement between CEUS and CT, according to Landis-Koch classification, was 0.76 (CI 0.33-1.19; p = 0.0165), which is excellent and higher than expected by random. Sensitivity of the test is 93.75% (15/16). Median time of follow-up after cryoablation is 22 months (15.5-36.5). CEUS has an excellent agreement with CT and a high sensitivity in the follow-up of SRMs treated with cryosurgery, demonstrating its usefulness. Due to these encouraging results, it could become a reference test in the near future for monitoring SRMs after ablative treatment.

EP159 Experience of cryoablation for small renal masses in our institute

EP159 Experience of cryoablation for small renal masses in our institute

Surgical cryoablation as an option for small renal masses in patients who are not ideal partial nephrectomy candidates: intermediate-term outcomes

There has been increasing interest in surveillance and ablative techniques for small renal masses (SRM), given the increasing number being diagnosed at smaller sizes. Of the currently available ablative techniques, radiofrequency ablation and cryoablation have been the popular ones. We describe our intermediate-term outcomes with using cryoablation for SRM in patients who were not ideal candidates for partial nephrectomy. Nineteen patients treated with cryoablation were included. Patients with renal lesions <4 cm were considered for cryoablation, and all patients were treated between 2002 and 2007. Access was either laparoscopic (transperitoneal) or via open surgical techniques. From 2002 to 2004, the CryoCare System (Endocare, Inc., Irvine, CA) was used, with probe sizes ranging from 3 to 5 mm. Before 2004, the SeedNet system (Galil Medical, Arden Hills, MN) was used, with 17-gauge (1.47 mm) IceRod cryoneedles. Recurrence-free survival (RFS) and overall survival (OS) were calculated using Kaplan Meier methodology. The mean age was 56.7 years. The mean tumour size was 2.6 cm (range 1.2-4.0 cm). There were no intraoperative or postoperative complications in the 19 patients. One patient has been lost to follow-up; mean follow up was 41.6 months (range 7-84 months) in the cohort. Recurrence, defined as either increase in size of lesion or enhancement on follow-up imaging, was seen in 4 patients. There was 1 non-cancer specific death, and 1 cancer specific death. The 4-year RFS rate and OS rate were 83.6% and 94.1%, respectively, in patients with SRM who were unsuitable for partial nephrectomy.

Percutaneous Computed Tomography–guided Renal Mass Radiofrequency Ablation versus Cryoablation: Doses of Sedation Medication Used

PurposeTo compare the amount of sedation medication administered during radiofrequency (RF) ablation versus cryoablation of small renal masses. Materials and MethodsRecords were retrospectively reviewed in patients who underwent percutaneous computed tomography–guided RF ablation and cryoablation of small renal masses from January 2002 to June 2011 for patient and tumor characteristics, amount of medications used for moderate sedation, and complications. Sedation was performed by giving patients titrated doses of midazolam and fentanyl. Additional medications were given if the desired level of sedation was not achieved. ResultsThere were 116 patients who underwent 136 ablation procedures; 71 patients underwent RF ablation, and 65 patients underwent cryoablation. RF ablation was associated with a significantly higher mean dose of fentanyl (mean dose for RF ablation, 236.43 μg; mean dose for cryoablation, 172.27 μg; P<.001). RF ablation was also associated with a higher mean dose of midazolam (mean dose for RF ablation, 4.5 mg; mean dose for cryoablation, 3.27 mg; P<.001). In the RF ablation group, two patients required additional sedation with droperidol. As a result of oversedation, two patients in the RF ablation cohort required sedation reversal with naloxone and flumazenil. None of the patients who underwent cryoablation required sedation reversal. No other sedation-related complications occurred. ConclusionsCryoablation of small renal masses was performed with less sedation medication than RF ablation. This finding suggests renal cryoablation is less painful than RF ablation; however, prospective studies with validated pain scales are needed to confirm these results.

Laparoscopic Renal Cryoablation: Single Institutional Experience from South America

Objective: Minimal invasive thermal ablative techniques are emerging as a viable option for patients who are not candidates for open, laparoscopic or robotic-assisted partial nephrectomy. Cryoablation is a low risk alternative with good oncologic outcomes. We present our initial experience with cryoablation for small renal masses using the laparoscopic approach. Patients and Methods: We prospectively collected the perioperative data of patients undergone renal cryoablation at our institution. From May/2009 to January/2011, 41 patients with incidental small renal mass were submitted to laparoscopic cryoablation. Results: The mean patient age was 58.8 years. The mean operative time was 115.4 ± 60.3 min and no patient needed blood transfusion. The mean of size tumors was 2.8 cm (1-5 cm). Intraoperative biopsies showed 27 (65%) malignant tumors, 5 (12%) oncocytomas, two (6%) angiomyolipomas 7 (17%) inconclusive. With a mean follow-up of 16 months (12-21), there were no significant differences between creatinine, estimated glomerular filtration rate and hemoglobin level before and after the procedure. There was no open conversion, kidney loss, urinary fistula, dialysis requirement or re-operations. Conclusion: Laparoscopic renal cryoablation is safe, with low complication rate and short learning curve.

R.E.N.A.L. Nephrometry Score Accurately Predicts Complications Following Laparoscopic Renal Cryoablation

The R.E.N.A.L. nephrometry is a standardized scoring system that quantifies the complexity of kidney tumors. We evaluated our experience with laparoscopic cryoablation and determined the ability of nephrometry to predict complications. We reviewed the records of all patients who underwent laparoscopic cryoablation from July 2005 to February 2010 at 3 institutions. The composite R.E.N.A.L. score was determined using preoperative imaging, and tumors were categorized as low (4-6), moderate (7-9) or high complexity (10-12). Perioperative data were analyzed to determine the presence of complications. The distribution of surgical complications and tumor categories was compared using the chi-square and Student's t test. Logistic regression was used to analyze the association between nephrometry score and postoperative complications. A total of 210 patients underwent laparoscopic cryoablation, 77 of whom had available preoperative imaging. Mean patient age was 64.5 years and mean tumor size was 2.6 cm (range 1 to 4.5). Mean nephrometry score was 6.1 (range 4 to 12). Of the tumors 47 (61%) were categorized as low, 23 (30%) as moderate and 7 (9%) as high complexity lesions. Overall there were 15 (19.5%) complications, including 7 (9.5%) major and 8 (10%) minor complications. There was a significant difference in complication rates among the low (47 patients, 0%), moderate (23 patients, 35%) and high complexity (7 patients, 100%) groups, respectively (p <0.001). On multivariate analysis nephrometry score was independently associated with a higher risk of postoperative complications (OR 2.23, 95% CI 1.05-2.11, p = 0.008). In a multi-institutional cohort of patients undergoing laparoscopic cryoablation, the R.E.N.A.L. nephrometry score is independently associated with the occurrence of complications. Therefore, nephrometry can be used to successfully stratify patients in terms of anticipated risk of complications which, in turn, may help with surgical decision making.

UP-01.203 Experience in Cryoablation of Small Renal Masses from a Single UK Centre

UP-01.203 Experience in Cryoablation of Small Renal Masses from a Single UK Centre

Second Prize: Recurrence Rates After Percutaneous and Laparoscopic Renal Cryoablation of Small Renal Masses: Does the Approach Make a Difference?

As radiologic detection of small renal masses increases, patients are increasingly offered percutaneous renal cryoablation (PRC) or transperitoneal laparoscopic renal cryoablation (TLRC). This multicenter experience compares these approaches. Between September 1998 and May 2010, review of our PRC and TLRC experience was performed. Patients with ≥ 12-month follow-up were included for analysis. Post-treatment surveillance consisted of laboratory studies and imaging at regular intervals. Treatment failure was considered if persistent mass enhancement or interval tumor growth was radiographically evident. Repeated biopsy and re-treatment were recommended in the event of recurrence. Sixty-one patients underwent PRC and 84 patients underwent TLRC. No significant differences were noted with respect to demographic factors. Mean tumor size was 2.7 ± 1.1 cm (PRC) and 2.5 ± 0.8 (TLRC) cm (P = 0.090). Mean follow-up was 31.0 ± 15.9 months (PRC) and 42.3 ± 21.2 (TLRC) months (P = 0.008), with local tumor recurrence noted in 10/61 (16.4%) PRC and 5/84 (5.9%) TLRC (P = 0.042). For PRC, disease-free survival (DFS) and overall survival (OS) were 93.7% and 88.9%, respectively, with four patients having evidence of disease at last follow-up. DFS and OS were 91.7% and 89.3% for TLRC, with seven patients having evidence of disease at last follow-up. DFS (P = 0.654) and OS (P = 0.939) were similar. In this multicenter study of well-matched cohorts, PRC had higher primary treatment failure rates than TLRC. While no differences were noted between DFS and OS, analysis is limited by intermediate follow-up. Further study is necessary to discern reasons for the higher recurrence rates in PRC and to determine what long-term consequences exist.

Results of laparoscopic cryoablation in the treatment of small renal masses

Context:Study of clinical outcome in renal cryoablation.Aims:Laparoscopic cryoablation (LCA) is emerging as a reliable treatment option for small renal masses (SRMs) particularly in elderly patients. Our aim was to study the results of cryoablation for small renal masses in our cohort of patients.Settings and Design:We retrospectively studied all patients who underwent LCA for SRMs between September 2005 and July 2008.Materials and Methods:All patients were discussed in our multidisciplinary meeting prior to cryoablation. Our LCA protocol included two freeze-thaw cycles, achieving a core temperature of –70°C and a peripheral temperature of at least –40°C. Follow-up included serum creatinine measurements and pre- and postcontrast CT scans at 3, 6, 12, 18, and 24 months and yearly thereafter.Statistical analysis used:Paired samples t-test was used to study statistical difference.Results:Twenty-two patients underwent LCA with a mean (range) age of 68 (39–81 years) years. The mean (range) tumor size was 29 (19–45 mm) mm. Two patients required blood transfusions, one patient developed pneumonia, and another patient developed a small area of skin necrosis at the cryoneedle entry site. The average (range) hospital stay was 4 (2–14 days) days. Twenty-one patients have had CT follow-up at a mean (range) of 24 (4–42 months) months. Three of the 21 tumors showed central enhancement on follow-up CT scans, consistent with treatment failure.Conclusions:Laparoscopic cryoablation is a safe treatment option for SRM in a selected group of patients.

Percutaneous vs surgical cryoablation of the small renal mass: is efficacy compromised?

• To review and analyse the cumulative literature to compare surgical and percutaneous cryoablation of small renal masses (SRMs). • A MEDLINE search was performed (1966 to February 2010) of the published literature in which cryoablation was used as therapy for localized renal masses. • Residual disease was defined as persistent enhancement on the first post-ablation imaging study, while recurrent disease was defined as enhancement after an initially negative postoperative imaging study, consistent with the consensus definition by the Working Group on Image-Guided Tumor Ablation. • Data were collated and analysed using the two-sample Mann-Whitney test and random-effects Poisson regression, where appropriate. • In all, 42 studies, representing 1447 lesions treated by surgical (n= 28) or percutaneous (n= 14) cryoablation were pooled and analysed. • No significant differences were detected between approaches regarding patient age (median 67 vs 66 years, P= 0.55), tumour size (median 2.6 vs 2.7 cm, P= 0.24),or duration of follow-up (median 14.9 vs 13.3 months, P= 0.40). • Differences in rates of unknown pathology also failed to reach statistical significance (14 vs 21%, P= 0.76). The difference in the rate of residual tumour was not statistically different (0.033 vs 0.046, P= 0.25), nor was the rate of recurrent tumour (0.008 vs 0.009, P= 0.44). • The reported rate of metastases was negligible in both groups, precluding statistical analysis. • Cryoablation has shown acceptable short-term oncological results as a viable strategy for SRMs. • Analysis of the cumulative literature to date shows that surgical and percutaneous cryoablation have similar oncological outcomes.

Standard of Care and New Operative Techniques for Small Renal Tumors: a Meta-analysis with a Special Focus on Cryoablation

Introduction: the aim of this article is to realize a meta-analysis of published data evaluating open nephrectomy, laparoscopic nephrectomy and cryoablation for small renal masses to define the current data, and to adjust oncological results for patients and follow-up heterogeneity by performing econometric estimations. Materials and methods: a systematic literature review using the STROBE checklist was performed for clinically localized sporadic renal masses from the beginning of January 1996 until October 31, 2008 . The main variables evaluated were patients’ age and sex, tumor size, ASA score, duration of follow-up, available clinical outcomes, pathological data, and oncological outcomes. Results: 152 studies representing 19,994 patients were analyzed. The authors found a significant lower operation time for percutaneous cryoablation, and a lower hospital stay and blood losses for all types of cryoablation (i.e. open, laparoscopic and percutaneous). No significant difference is found between cryoablation and resection methods as regard to complication rates. When adjusting oncological results for patients and follow-up heterogeneity, higher recurrence rates at five years are found for cryoablation, on the contrary, no difference is found for specific-cancer survival rates at five years. Conclusions: cryoablation is a safe and less invasive procedure than resection methods. However, its long term efficacy has not yet been established and a more stringent selection of patients is needed to reduce recurrence rates.

Renal Functional Outcomes After Cryoablation of Small Renal Masses

Renal function outcomes after renal cryosurgery have not been widely scrutinized. We report 2-year renal function outcomes from a single-center cohort of patients who were treated with cryoablation for small renal masses. We performed a retrospective review of our laparoscopic and percutaneous renal cryoablation experience between January 2003 and April 2007. Global renal function was assessed using measured serum creatinine and estimated glomerular filtration rate (eGFR) (MDRD equation). Chronic kidney disease (CKD) was defined as a serum creatinine level >2.0 mg/dL or eGFR <60 mL/min/1.73 m(2). Sixty-two patients were included in the analysis. Mean follow-up was 30 months (range 13-63 mos). Mean tumor size was 2.33 cm (range 1-4.6 cm). Comorbid conditions were prevalent: 77% hypertension, 35% hyperlipidemia, 31% diabetes mellitus, 39% tobacco use, and 32% heart disease (coronary artery disease/congestive heart failure). Based on eGFR calculations, preoperative CKD was noted in 17 of 62 (27%) patients. De novo CKD was noted in 5 of 45 (11%) patients. Patients in whom de novo CKD developed had lower pretreatment eGFR (71.0 vs 98.4 60 mL/min/1.73 m(2), P = 0.03) and larger tumor size (2.94 vs 2.19 cm, P = 0.04) compared with patients who were maintaining normal renal function. When CKD was defined as creatinine level >2.0 mg/dL, only one and six patients were identified with preoperative and de novo CKD, respectively. In a cohort of renal cryosurgery patients who were characterized by highly prevalent medical comorbidities, renal function was generally well maintained, with a low rate of de novo CKD based on eGFR calculations. A serum creatinine level >2.0 mg/dL was a less sensitive measure of CKD.

The R.E.N.A.L. Nephrometry Score: A Comprehensive Standardized System for Quantitating Renal Tumor Size, Location and Depth

Treatment decisions for renal malignancies depend largely on qualitative data, including a description of tumor anatomy and the experience of the treating surgeon. Currently characterization of renal tumor anatomical elements is descriptive and lacks standardization. Surgical decision making and data set comparisons would be significantly enhanced by a consistent, reproducible system that quantitates the pertinent characteristics of localized renal lesions. We have developed and propose a standardized nephrometry scoring system (R.E.N.A.L. Nephrometry Score) to quantify the anatomical characteristics of renal masses on computerized tomography/magnetic resonance imaging. The nephrometry score is based on 5 critical and reproducible anatomical features of solid renal masses. Of the 5 components 4 are scored on a 1, 2 or 3-point scale with the 5th indicating the anterior or posterior location of the mass relative to the coronal plane of the kidney. We applied the R.E.N.A.L. Nephrometry Score to 50 consecutive masses resected at Fox Chase Cancer Center. The R.E.N.A.L. Nephrometry Score consists of (R)adius (tumor size as maximal diameter), (E)xophytic/endophytic properties of the tumor, (N)earness of tumor deepest portion to the collecting system or sinus, (A)nterior (a)/posterior (p) descriptor and the (L)ocation relative to the polar line. The suffix h (hilar) is assigned to tumors that abut the main renal artery or vein. The nephrometry scoring system accurately classified the complexity of 50 consecutive tumors undergoing excision at our institution. Standardized reporting of renal tumor size, location and depth is essential for decision making and effective comparisons. The R.E.N.A.L. Nephrometry Score is a reproducible standardized classification system that quantitates the salient anatomy of renal masses. This novel approach for the systematic characterization of renal tumors provides a tool for meaningful comparisons of renal masses in clinical practice and in the urological literature.