Eric H. Kim

Percutaneous cryoablation of renal masses: Washington University experience of treating 129 tumours

For patients who are unfit for extirpative surgery, percutaneous cryoablation (PCA) presents a minimally‐invasive alternative for the treatment of renal masses. PCA has been demonstrated to be safe, with complication rates <10% being reported consistently. Studies have suggested that a minimal and insignificant decline in renal function can occur after PCA. Finally, among studies with a follow‐up >20 months, treatment success rates range from 75% to 96%. However, longer‐term oncological and functional results for patients treated with PCA are relatively limited. The present study profiles one of the largest reported experiences with PCA for renal masses: 129 tumours in 124 patients. Our complication rate was comparable to that observed in other reported studies. At a mean follow‐up of 30 months, treatment success was achieved in 87% of tumours, which is in line with published PCA success rates. On multivariable analysis, tumour size >3.0 cm was found to be significantly associated with treatment failure. A minimal but statistically significant renal functional decline was observed, with 20% of patients experiencing a progression in National Kidney Foundation‐Chronic Kidney Disease stage. On multivariable analysis, age >70 years, hilar tumour location and postoperative day 1 estimated glomerular filtration rate <60 mL/min/1.73 m2 were found to be significantly associated with renal functional decline. The present study confirms that PCA of renal masses represents a safe alternative to surgery in patients with substantial medical comorbidities. In the present cohort, baseline patient and tumour characteristics probably impact the risk of tumour recurrence, as well as renal disease progression, after PCA.

Renal Cryoablation Versus Robot-Assisted Partial Nephrectomy: Washington University Long-Term Experience

BACKGROUND AND PURPOSE American Urological Association guidelines endorse partial nephrectomy as the preferred treatment for patients with small renal masses, while considering patients with significant comorbidities potential candidates for ablative therapy. We compared perioperative, renal functional, and oncologic outcomes of renal cryoablation and robot-assisted partial nephrectomy (RAPN) based on our long-term institutional experience. PATIENTS AND METHODS A retrospective review evaluated 267 patients who underwent laparoscopic or percutaneous cryoablation (July 2000-June 2011) and 233 patients who underwent RAPN (June 2007-September 2012) for enhancing renal masses at Washington University. RESULTS The perioperative complication rate was 8.6% in the cryoablation group vs 9.4% in the RAPN group (P = 0.75). There was no significant difference in complication risk between the two treatment modalities on multivariate analysis. Estimated glomerular filtration rate (eGFR) at last follow-up was 6% lower than preoperative eGFR in the cryoablation group and 13% lower in the RAPN group (P<0.01). The advantage of cryoablation in preserving renal function persisted on multivariate analysis (P = 0.02). In patients with pathologically proven renal-cell carcinoma, 5-year Kaplan-Meier disease-free survival (DFS), cancer-specific survival (CSS), and overall survival was 83.1%, 96.4%, and 77.1% in the cryoablation cohort vs 100%, 100%, and 91.7% in the RAPN group. Mean time to recurrence was 16.2 months (range 0.03-42.0 mos). Cryoablation was associated with increased recurrence risk (hazard ratio [HR] = 11.4, P = 0.01) on multivariate analysis. CONCLUSIONS Cryoablation and RAPN are safe alternatives for managing renal masses amenable to nephron-sparing interventions, offering acceptable morbidity and excellent renal preservation. While RAPN offers improved DFS, for those willing to undergo close postoperative monitoring and accept the potential need for re-treatment of recurrent disease, cryoablation offers excellent long-term CSS.

Prostate-specific antigen-based screening: controversy and guidelines

Although prostate-specific antigen (PSA) screening has improved the detection of prostate cancer, allowing for stage migration to less advanced disease, the precise mortality benefit of early detection is unclear. This is in part due to a discrepancy between the two large randomized controlled trials comparing PSA screening to usual care. The European Randomized Study of Screening for Prostate Cancer (ERSPC) found a survival benefit to screening, while the United States Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial did not. Furthermore, the benefit of immediate surgical intervention for screen-detected prostate cancer is unclear, as the results superficially differ between the two large randomized controlled trials comparing prostatectomy to observation. The Prostate Cancer Intervention Versus Observation Trial (PIVOT) found no survival benefit for prostatectomy in PSA screened U.S. men, while the Scandinavian Prostate Cancer Group Study Number Four (SPCG-4) found a survival benefit for prostatectomy in clinically diagnosed prostate cancer. As a result of the controversy surrounding PSA screening and subsequent prostate cancer treatment, guidelines vary widely by organization.

Laparoscopic Cryoablation of Renal Masses: Single-center Long-term Experience

OBJECTIVE To evaluate perioperative and long-term functional and oncological outcomes of laparoscopic cryoablation (LCA) performed at Washington University. METHODS A retrospective chart review was performed evaluating 62 consecutive patients who underwent LCA at our institution between 2000 and 2005. RESULTS Mean age-adjusted Charlson Comorbidity Index (CCI) was 6.1 (SD, 2.1; 95% confidence interval [CI], 5.6-6.6). Mean tumor size was 2.52 cm (SD, 0.99; CI, 2.3-2.8). Mean operative time was 162.0 minutes (SD, 66.6; CI, 142.0-182.1). Mean estimated blood loss was 84.9 mL (SD, 102; CI, 58.6-111.2). Mean hospital stay was 2.6 days (SD, 1.90; CI, 2.1-3.1). The perioperative complication rate was 9.7% (Clavien 1-2). Among patients with biopsy proven, localized renal cell carcinoma, the 6-year Kaplan-Meier estimated disease-free survival (DFS) was 80%; cancer-specific survival (CSS) was 100%; and overall survival (OS) was 76.2%. Mean follow-up in this subset was 76.0 months (SD, 39.3; CI, 62.7-89.4; n = 35), whereas mean time to cancer recurrence was 27.6 months (SD, 11.2; CI, 15.9-39.3; n = 6). Tumor size ≥2.6 cm was the only predictor of cancer recurrence in a multivariate Cox proportional hazards model (hazard ratio [HR] = 28.9; P = .046; n = 35). Mean preoperative estimated glomerular filtration rate (eGFR) was 68.3 (SD, 22.3; CI, 62.1-74.5), compared to 64.5 mL/min/1.73 m(2) (SD, 28.9; CI, 56.5-72.6) at last follow-up (P = .12; n = 52). Excluding patients requiring secondary ablative or extirpative treatments for recurrent renal cell carcinoma, preoperative eGFR <60 mL/min/1.73 m(2) (odds ratio [OR] = 88.3; P = .036) and age-adjusted CCI ≥6 (OR = 32.4; P = .046) were the only factors predicting renal disease progression on multiple logistic regression (n = 47). CONCLUSION We report what is by far the longest follow-up to date of postlaparoscopic cryoablation changes in eGFR and note excellent long-term renal functional outcomes. For those willing to accept the potential need for retreatment for recurrent disease, LCA offers excellent long-term CSS.

Comparison of Laparoscopic and Percutaneous Cryoablation for Treatment of Renal Masses

OBJECTIVE To compare perioperative and oncologic outcomes between laparoscopic (LCA) and percutaneous cryoablation (PCA) and identify predictors of treatment failure after cryoablation. METHODS Retrospective analysis was performed on 145 patients undergoing LCA and 118 patients undergoing PCA at our institution between July 2000 and June 2011. RESULTS LCA and PCA were performed on 167 and 123 tumors, respectively. Perioperative complication rates were 10% for both the groups. Mean length of stay was significantly shorter for the PCA group (2.1 ± 0.5 vs 3.5 ± 3.1 days, P <.01). Both groups had a comparable decline in estimated glomerular filtration rate at most recent follow-up (LCA 3.8 ± 18.5 mL/min/1.73 m(2) vs PCA 6.6 ± 17.1 mL/min/1.73 m(2), P = .21). Mean oncologic follow-up was 71.4 ± 32.1 months for LCA and 38.6 ± 19.6 months for PCA. Kaplan-Meier estimated 5-year overall and recurrence-free survival were 79.3% and 85.5%, respectively, for LCA and 86.3% and 86.3%, respectively, for PCA. Multivariate Cox proportional hazards analysis demonstrated that cryoablation approach (LCA vs PCA) was not predictive of overall mortality or disease recurrence (P = .36 and .82, respectively). Predictors of overall mortality included age-adjusted Charlson comorbidity index ≥ 6 (P = .01) and preoperative estimated glomerular filtration rate <60 mL/min/1.73 m(2) (P = .02). Predictors of recurrence included tumor size ≥ 3 cm (P <.01), body mass index ≥ 30 kg/m(2) (P = .01), and endophytic growth (P = .04). CONCLUSION Mean length of stay was shorter for patients undergoing PCA as compared with LCA. Complication rates and decline in renal function at most recent follow-up were similar between groups. Oncologic outcomes were influenced by baseline patient and tumor characteristics rather than the cryoablation approach.

Off-Clamp Robot-Assisted Partial Nephrectomy: Initial Washington University Experience

BACKGROUND AND PURPOSE Because of the impact warm ischemia time may have on renal function, various surgical techniques have been proposed to minimize or eliminate warm ischemia. The purpose of this study is to evaluate our initial renal functional outcomes of off-clamp robot-assisted partial nephrectomy (RAPN), while assessing the safety profile of this unconventional surgical approach. PATIENTS AND METHODS We performed a retrospective review of our off-clamp RAPN experience between August 2007 and January 2012. All patients with baseline and postoperative serum creatinine determinations were included. Patient demographics, operative information, perioperative outcomes, and renal functional outcomes were evaluated for this cohort. RESULTS Forty-two patients with a mean age of 59.9 years (standard deviation [SD]=12) had a median follow-up of 100 days (range 1-1007 days). In all cases, warm ischemia time was 0 minutes. Mean operative time was 143 minutes (SD=59), and median estimated blood loss was 138 mL (range 50-1500 mL). No intraoperative complications were encountered, and all surgical margins were negative. Our postoperative complication rate was 14.3%. At the most recent follow-up, the mean estimated glomerular filtration rate (eGFR) was 76.2 mL/min/1.73 m(2) (SD=27.6), compared with 78.5 mL/min/1.73 m(2) (SD=28.9) preoperatively (P=0.11). Therefore, the mean eGFR decline of 2.3 mL/min/1.73 m(2) (SD=9.1) was not significant. CONCLUSIONS Off-clamp RAPN is associated with minimal morbidity and minimal decline in renal function on short-term follow-up. Further studies and continued monitoring of renal function are needed to determine if off-clamp RAPN provides any advantage in renal function preservation relative to the traditional RAPN with vascular clamping.

Retroperitoneal Robot-Assisted Partial Nephrectomy for Posterior Renal Masses Is Associated with Earlier Hospital Discharge: A Single-Institution Retrospective Comparison

PURPOSE To compare perioperative outcomes, specifically hospital length of stay (LOS), after retroperitoneal and conventional transperitoneal robot-assisted partial nephrectomy (RAPN). PATIENTS AND METHODS We retrospectively compared consecutive patients with a posterior renal mass undergoing retroperitoneal RAPN (n=116) versus transperitoneal RAPN (n=97) at our institution between July 2007 and March 2014. The surgical approach was based on patient and tumor characteristics, history of abdominal surgery, and surgeon preference. The primary outcome was postoperative LOS, and secondary outcomes included complication rate, inpatient narcotic pain medication use, and inpatient antiemetic use. RESULTS Baseline patient and tumor characteristics were similar between groups. A significantly great proportion of patients undergoing retroperitoneal RAPN had LOS equal to 1 day (57% vs 10%, P<0.01). Complication rates were similar between groups (P=0.37). Median pain medication use was also similar between groups (P=0.85). A significantly greater proportion of retroperitoneal RAPN patients, however, needed no antiemetics postoperatively (59% vs 43%, P=0.02). On multivariate analysis, transperitoneal RAPN was a significant predictor of LOS greater than 1 day (odds ratio=7.4, P<0.01), when controlling for age, sex, body mass index, patient comorbidity, previous abdominal surgery, baseline kidney function, nephrometry score, and tumor size. CONCLUSIONS For patients with posterior renal masses, retroperitoneal RAPN significantly reduces their hospital LOS when compared with transperitoneal RAPN.

Endopyelotomy for pediatric ureteropelvic junction obstruction: a review of our 25-year experience.

PURPOSE We elucidate the role of endopyelotomy as a primary and secondary intervention for ureteropelvic junction obstruction in children. MATERIALS AND METHODS We retrospectively identified 79 pediatric patients who underwent endopyelotomy for ureteropelvic junction obstruction between 1986 and 2011. Eleven patients were lost to followup and were excluded from analysis. Patient demographics, operative information, complications and success rates were reviewed for the remaining 68 patients. Treatment success was defined as the absence of symptom recurrence and improved radiographic features on ultrasound, computerized tomography, diuretic renogram or excretory urogram at most recent followup. RESULTS Primary endopyelotomy data were analyzed in 37 patients with a median age of 11.1 years. The success rate was 65% at a median followup of 34 months (range 1.5 to 242). Treatment failure occurred in 13 patients with a median time to failure of 8 months (range 1.5 to 131). There were 8 cases of failure during 12 months of surgery. Secondary endopyelotomy data were analyzed in 31 patients with a median age of 6.5 years. The success rate was 94% at a median followup of 61 months (range 1 to 204). Treatment failure occurred in 2 patients at 1 and 6 months. Approximately two-thirds of all procedures used an antegrade approach. CONCLUSIONS Primary endopyelotomy is significantly less successful than pyeloplasty in the treatment of ureteropelvic junction obstruction in pediatric patients. However, secondary endopyelotomy following failed pyeloplasty represents a viable alternative to redo pyeloplasty.

Robot-assisted partial nephrectomy: off-clamp technique.

Robot-assisted partial nephrectomy (RAPN) has been established as a viable alternative to open and laparoscopic partial nephrectomy for small renal tumors. Multiple variations in surgical technique have been described to reduce warm ischemia time (WIT). We present our off-clamp technique for RAPN. From August 2007 to January 2012, off-clamp RAPN was performed on 47 tumors in 39 patients. WIT was 0 minutes in all cases. The mean operative time was 147 minutes (SD=58); the mean and median estimated blood loss were 219 mL (SD=253) and 150 mL (range 50-1500), respectively; the mean length of stay was 1.9 days (SD=1.1). There were no intraoperative complications, and results for all surgical margins were negative. In experienced hands, our off-clamp technique for RAPN is a safe and feasible technique that eliminates WIT.

Magnetic resonance imaging-targeted vs. conventional transrectal ultrasound-guided prostate biopsy: Single-institution, matched cohort comparison

OBJECTIVES To compare magnetic resonance imaging-targeted biopsy (MRITB) and conventional transrectal ultrasound-guided biopsy (TRUSGB) in the detection of prostate cancer (PCa) at our institution. METHODS Our prospective registry of patients undergoing prostate MRITB from December 2010 to July 2013 was analyzed. Patients were matched one-to-one to patients who underwent TRUSGB based on the following characteristics: age, prostate-specific antigen level, prostate volume, race, family history of PCa, initial digital rectal examination (DRE), prior use of 5-alpha reductase inhibitor, and prior diagnosis of PCa. MRITB was performed using a TargetScan system with the patient under general anesthesia. Magnetic resonance imaging suspicious regions (MSRs) were targeted with cognitive registration, and a full TargetScan template biopsy (TSTB) was also performed. RESULTS In total, 34 MRITB patients were matched individually to 34 TRUSGB patients. As compared with TRUSGB, patients who underwent MRITB had a greater overall rate of PCa detection (76% vs. 56%, P = 0.12) and a significantly higher number with Gleason score≥7 (41% vs. 15%, P = 0.03), whereas the rates of Gleason score 6 PCa detection were similar between MRITB and TRUSGB (35% vs. 41%, P = 0.80). As compared with the TSTB, magnetic resonance imaging suspicious regions-directed biopsies during MRITB had a significantly higher overall PCa detection (54% vs. 24%, P<0.01) and Gleason score≥7 PCa detection (25% vs. 8%, P<0.01). When compared with TSTB, TRUSGB had similar detection rates for benign prostate tissue (76% vs. 79%, P = 0.64), Gleason score 6 PCa (16% vs. 14%, P = 0.49), and Gleason score ≥7 PCa detection (8% vs. 7%, P = 1.0). CONCLUSIONS Cognitive registration MRITB significantly improves the detection of Gleason score≥7 PCa as compared with conventional TRUSGB.