Vincent G. Bird

Flexible ureterorenoscopy and holmium laser lithotripsy for the management of renal stone burdens that measure 2 to 3 cm: a multi-institutional experience.

BACKGROUND AND PURPOSE Percutaneous nephrostolithotomy (PCNL) is the current standard of care for management of large renal stones (>2 cm). Recent studies have evaluated flexible ureterorenoscopy (URS)/holmium laser lithotripsy as an alternative treatment for patients with contraindications to or preference against PCNL. Stones in an intermediate size range (2-3 cm) may be most amenable to URS/laser lithotripsy as definitive treatment in a single stage. We report a multi-institutional series of URS/laser lithotripsy for renal stone burdens that measure 2 to 3 cm. PATIENTS AND METHODS Patients who underwent URS/holmium laser lithotripsy for renal stones that measured 2 to 3 cm were identified retrospectively at three tertiary care centers. Demographic information, disease characteristics, and perioperative and postoperative data were gathered. Patients with renal stone burdens of 2 to 3 cm who were treated by URS/laser lithotripsy and had at least one postoperative visit and imaging study were included. Stone clearance was evaluated using 0-2 mm and <4 mm residual stone burden on postoperative imaging. RESULTS One hundred and twenty patients underwent URS/holmium laser lithotripsy for renal stones of 2 to 3 cm. Mean stone burden was 2.4 cm, and mean body mass index was 29.3 kg/m². Indications for URS/laser lithotripsy vs PCNL included patient preference (57), technical or anatomic factors (24), patient comorbidities (17), failed shockwave lithotripsy (9), patient body habitus (3), solitary kidney (3), chronic renal insufficiency (3), and strict anticoagulation (2). Thirty-one (26%) patients had stent placement preprocedure, and 94 (78%) patients underwent outpatient surgery. A ureteral access sheath was used in 67%. One hundred and one (84%) patients underwent single-stage procedures. There was one intraoperative complication (ureteral perforation), and there were eight minor postoperative complications (6.7%). The reoperation rate through the mean 18-month follow-up was 3/120 or 2.5%. Seventy-six (63%) patients had residual stone burden of 0 to 2 mm, and 100 (83%) patients had residual burden of <4 mm. CONCLUSIONS We demonstrate that single-stage URS/holmium laser lithotripsy is effective for management of renal stones that measure 2 to 3 cm through intermediate follow-up. Staged procedures can be used selectively for technical reasons or disease factors. Although PCNL achieves superior stone clearance overall, URS/laser lithotripsy is a viable treatment option for selected patients.

Practice patterns in the treatment of large renal stones.

PURPOSE To determine the current practice patterns of a large group of urologists in the treatment of large renal stones. MATERIALS AND METHODS A survey was sent to all actively practicing members of the North Central Section of the American Urological Association. The questions pertained to age, time in practice, type of practice, time devoted to treating stones, residency training, case scenarios with treatment options, and whether they or a radiologist performed percutaneous access. The data were statistically analyzed. RESULTS The response rate was 51% (564/1102 surveys returned). Three quarters (73%) of the urologists were comfortable performing percutaneous nephrolithotomy (PCNL), and 35% gave reasons they do not perform PCNL. Only 11% of those performing PCNL routinely obtained the percutaneous access themselves. Trends in the analysis included: (1) those trained to perform PCNL during residency were more often comfortable with this procedure; (2) younger urologists were more comfortable performing PCNL, even if they had been in practice for only a short time; (3) urologists in private practice were nearly as comfortable performing PCNL as were academic urologists; (4) urologists not comfortable with PCNL more often recommended SWL over PCNL as a primary treatment for moderate/large renal stones; and (5) few urologists routinely obtained percutaneous access themselves. CONCLUSIONS Many urologists trained in recent years are comfortable performing PCNL. The type of training received influences treatment recommendations, and percutaneous access is most often obtained by/in conjunction with radiologists. This information may be useful in guiding residency training programs in the preparation of residents for the treatment of large renal stones.

Evaluation and Comparison of Urolithiasis Scoring Systems Used in Percutaneous Kidney Stone Surgery

PURPOSE Contemporary predictive tools for percutaneous nephrolithotomy outcomes include the Guy stone score, S.T.O.N.E. nephrolithometry and the CROES nephrolithometric nomogram. We compared each scoring system in the same cohort to determine which was most predictive of surgical outcomes. METHODS We retrospectively reviewed the records of patients who underwent percutaneous nephrolithotomy between 2009 and 2012 at a total of 3 academic institutions. We calculated the Guy stone score, the S.T.O.N.E. nephrolithometry score and the CROES nephrolithometric nomogram score based on preoperative computerized tomography images. A single observer at each institution reviewed all images and assigned scores. Univariate and multivariate analysis was done to determine the most predictive scoring system. RESULTS We enrolled 246 patients in study. In stone-free patients vs those with residual stones the mean Guy score was 2.2 vs 2.7, the mean S.T.O.N.E. score was 8.3 vs 9.5 and the mean CROES nomogram score was 222 vs 187 (each p <0.001). Logistic regression revealed that the Guy, S.T.O.N.E. nephrolithometry and CROES nomogram scores were significantly associated with stone-free status (p = 0.02, 0.004 and <0.001, respectively). The Guy and S.T.O.N.E. nephrolithometry scores were associated with estimated blood loss (p <0.0001 and 0.03) and length of stay (p = 0.03 and 0.009, respectively). The CROES nomogram did not predict estimated blood loss or length of stay. CONCLUSIONS All scoring systems and the stone burden equally predicted stone-free status. The Guy and S.T.O.N.E. nephrolithometry scores were associated with estimated blood loss and length of stay. A single scoring system should be adopted to unify reporting.

Management of Renal Masses with Laparoscopic-Guided Radiofrequency Ablation versus Laparoscopic Partial Nephrectomy

BACKGROUND AND PURPOSE Laparoscopic-guided radiofrequency ablation (LRFA) has been introduced as a minimally invasive nephron-sparing management option for renal tumors. Many patients who desire treatment present with multiple comorbidities, which poses a therapeutic challenge. Our purpose is to determine if multipass LRFA is comparable, in terms of surgical risk and immediate postoperative outcomes, to laparoscopic partial nephrectomy (LPN). PATIENTS AND METHODS A retrospective study identified 36 and 33 patients who underwent LRFA and LPN, respectively. Perioperative demographic data, tumor characteristics, and follow-up data were evaluated. Statistical analysis was performed using the Student t test and chi-square analysis. RESULTS Age, American Society of Anesthesiology score, and Charlson Comorbidity Index were significantly higher in the LRFA group than the LPN group (P < 0.001). Average tumor size was 2.8 cm and 3.1 cm for the LRFA and LPN groups, respectively. There were no significant differences in change between the preoperative and postoperative creatinine/glomerular filtration rate values or perioperative complication rates for the groups. Estimated blood loss and length of stay were significantly lower for the LRFA group than the LPN group (P < 0.05). Follow-up ranged 6 to 23 months and 6 to 58 months for the LRFA and the LPN groups, respectively. There has been no evidence of tumor recurrence in the follow-up period. CONCLUSIONS We present our initial report comparing patients undergoing LRFA v LPN for the management of renal tumors. Our preliminary results with our experience with multipass laparoscopic-guided RFA demonstrate that this technique can be safely used in an elderly, higher risk population. Long-term follow-up is needed to determine oncologic efficacy.

Prediction of single procedure success rate using S.T.O.N.E. nephrolithometry surgical classification system with strict criteria for surgical outcome.

OBJECTIVE To evaluate the S.T.O.N.E. nephrolithometry scoring system for percutaneous nephrolithotomy using computerized tomography (CT) imaging with strict criteria for stone clearance. MATERIALS AND METHODS We analyzed a cohort of 122 patients who consecutively underwent primary percutaneous nephrolithotomy from July 2010 to March 2012 at our university-based referral hospital. All patients routinely have preoperative and postoperative CT imaging for stone burden determination. Primary outcome (residual stone) was scored as 0-2, 3-4, and >4 mm. All S.T.O.N.E. nephrolithometry parameters were recorded and scored as per published definition. The t test was used for continuous variables, and the chi-square testing or the Fisher exact test (when counts were small) was used for categorical covariates. S.T.O.N.E. score correlation with stone-free status was analyzed by logistic regression. RESULTS Nephrolithometry score ranged from 5 to 13 with a mean of 9.5. Postoperative CT for residual stone showed 67 (54.9%), 26 (21.3%), and 29 (23.8%) patients had 0-2, 3-4, and >4 mm residual stone, respectively. Mean nephrolithometry scores for residual stone of 0-2, 3-4, and >4 mm were 8.87, 9.73, and 10.79 respectively (P <.0001). There were 11 (9.8%) complications. CONCLUSION With use of strict CT imaging criteria for assessment of residual stone status, the S.T.O.N.E. scoring system is reproducible and predictive of treatment success. Further investigation is required to both validate this model and to determine if other predictive parameters will improve it as a predictive model.

Clinical, Pathologic, and Functional Outcomes After Nephron-Sparing Surgery in Patients with a Solitary Kidney: A Multicenter Experience

BACKGROUND AND PURPOSE Surgical management of a renal neoplasm in a solitary kidney is a balance between oncologic control and preservation of renal function. We analyzed patients with a renal mass in a solitary kidney undergoing nephron-sparing procedures to determine perioperative, oncologic, and renal functional outcomes. PATIENTS AND METHODS A multicenter study was performed from 12 institutions. All patients with a functional or anatomic solitary kidney who underwent nephron-sparing surgery for one or more renal masses were included. Tumor size, complications, and recurrence rates were recorded. Renal function was assessed with serum creatinine level and estimated glomerular filtration rate. RESULTS Ninety-eight patients underwent 105 ablations, and 100 patients underwent partial nephrectomy (PN). Preoperative estimated glomerular filtration rate (eGFR) was similar between the groups. Tumors managed with PN were significantly larger than those managed with ablation (P<0.001). Ablations were associated with a lower overall complication rate (9.5% vs 24%, P=0.01) and higher local recurrence rate (6.7% vs 3%, P=0.04). Eighty-four patients had a preoperative eGFR ≥60 mL/min/1.73 m(2). Among these patients, 19 (23%) fell below this threshold after 3 months and 15 (18%) at 12 months. Postoperatively, there was no significant difference in eGFR between the groups. CONCLUSIONS Extirpation and ablation are both reasonable options for treatment. Ablation is more minimally invasive, albeit with higher recurrence rates compared with PN. Postoperative renal function is similar in both groups and is not affected by surgical approach.

Initial Clinical Experience With Use of Ureteral Access Sheaths in the Diagnosis and Treatment of Upper Tract Urothelial Carcinoma

OBJECTIVE To describe our experience with ureteral access sheaths in the diagnosis and treatment of upper tract urothelial carcinoma. METHODS We retrospectively identified a patient cohort who underwent ureteroscopy for suspicion of upper tract urothelial carcinoma and identified those with placement of a ureteral access sheath. Records were reviewed for demographic information, comorbidity data, operative complications, and pathology results. The histologic grade of ureteroscopic biopsies and nephroureterectomy specimens were evaluated for concordance. RESULTS A total of 125 patients underwent 235 procedures for known or suspected upper tract urothelial carcinoma. Access sheaths were used in patients in whom significant urothelial lesions were noted in the proximal upper urinary tract. A total of 64 patients underwent 85 sheath-inclusive procedures. Sheath deployment was successful in 83 (97.6%) of the 85 procedures. Biopsies yielded specimen adequate for histopathologic diagnosis in 75 (90.4%) of 83 cases. No ureteral access sheath-related complications were noted. Of the 125 patients, 34 underwent removal of 35 renal units. The concordance of tumor grade between biopsy and nephroureterectomy specimens was 88.6% (P=.0002). CONCLUSION Ureteral access sheaths are safe for use in the diagnosis and treatment of upper tract urothelial carcinoma. Sheath placement facilitated the acquisition of multiple biopsy specimens adequate for histopathologic evaluation. Our technique precluded the need for repeat ureteroscopy to establish a diagnosis. Biopsies obtained through an access sheath were highly predictive of tumor grade in nephroureterectomy specimens.

Laparoscopic Radical Nephrectomy for Patients with T2 and T3 Renal-Cell Carcinoma: Evaluation of Perioperative Outcomes

PURPOSE Laparoscopic radical nephrectomy (LRN) is considered standard of care for T1 renal tumors not amenable to nephron-sparing surgery. Indications are now expanding to include patients with T2 or T3 tumors. The purpose of this study is to evaluate LRN as a minimally invasive procedure for treatment of advanced stage renal tumors. MATERIALS AND METHODS We performed a retrospective analysis of a cohort of consecutive patients with renal tumors undergoing LRN for clinical stages T1 to T3. Parameters examined included patient demographics, medical comorbidities, tumor characteristics, perioperative outcomes, and complications. RESULTS In all, 252 kidneys were removed from 247 consecutive patients undergoing LRN; 246/252 (97.6%) kidneys contained renal-cell carcinoma and 55 (21.8%) patients had pT2/T3 disease. Mean pathologic tumor size in the T1 and T2/T3 groups was 4.1 and 7.8 cm, respectively. Compared with patients with T1 tumor, patients with T2/T3 tumor had higher body mass index (p = 0.010), higher specimen weight (p = 0.002), higher mean Fuhrman grade (p = 0.014), and more postoperative complications (p = 0.035). Mean blood loss for T1 and T2/T3 patients was 133 and 198 cc, respectively; 3/197 patients (1.5%) and 4/55 patients (7.3%) in the T1 and T2/T3 groups received blood transfusion, respectively (p < or = 0.05). CONCLUSIONS LRN for the treatment of clinical stage T2 and T3 disease should be considered. LRN can be safely performed with good perioperative outcome. Blood transfusion and complication rates are higher for LRN in pT2/T3 patients. However, the decision to modify surgical technique should be considered when either oncologic efficacy or patient safety is a concern.

Diagnostic Yield of Renal Biopsy Immediately Prior to Laparoscopic Radiofrequency Ablation: A Multicenter Study

INTRODUCTION Ablative therapy is increasing for the management of small renal masses. Laparoscopic as well as percutaneous cryotherapy and radiofrequency ablation (RFA) have been utilized. Herein we review our experience with renal biopsy immediately prior to laparoscopic RFA. METHODS AND MATERIALS A prospectively collected database containing all patients who underwent laparoscopic RFA by three different surgeons at two different institutions was reviewed. Renal biopsies were performed in each patient during transperitoneal laparoscopy after mobilization of the kidney and prior to RFA. The biopsy needle was passed percutaneously via a sheath through the abdominal wall. Multiple core biopsies (3-5) were taken under visual and ultrasonic guidance. All were submitted for permanent pathologic sectioning. RESULTS 138 patients underwent renal biopsy prior to RFA. Mean tumor size was 3.0 cm (range 1.0-6.9). The mean age was 72 years (range 39-90). There were 42 females and 96 males. Mean blood loss was 28 ml (0-400 ml). Only 5 patients lost more than 50 ml, and in each case the bleeding was associated with complicated renal mobilization and dissection prior to biopsy. Final pathology revealed renal cell carcinoma in 95, oncocytic neoplasm in 26, and angiomyolipoma in 9.8 patients were considered to have nondiagnostic biopsies. In this group, final pathology revealed benign cysts in 3, inconclusive specimens in 3, fibrosis in 1, and normal tissue in 1. Hence, a clear diagnosis was possible in 130 of 138 patients, which is 94.2%. RCC was diagnosed in 68.8% of the patients, and in 73.1% of the conclusive biopsies. Eight patients had perioperative complications, including low-grade fevers (2) perirenal/retroperitonal hematoma (2), pleural tear/pneumothorax (2), CHF exacerbation, and wound infection. CONCLUSIONS In our multicenter experience, renal biopsy of 138 renal lesions at the time of laparoscopic RFA had a diagnostic yield of 94.2%. RCC was diagnosed in 68.8% of the patients, and in 73.1% of the conclusive biopsies.

Validation and Reliability of the Wisconsin Stone Quality of Life Questionnaire

Purpose: WISQOL (Wisconsin Stone Quality of Life questionnaire) is a disease specific, health related quality of life measure designed for patients who form kidney stones. The purpose of this study was to demonstrate the external and convergent validity of WISQOL and assess its psychometric properties. Materials and Methods: At the WISQOL creation site (development sample) and at 8 geographically diverse centers in the United States and Canada (consortium sample) patients with a history of kidney stones were recruited. Item response option variability, correlation patterns and internal consistency were compared between samples. Convergent validity was assessed by patients who completed both WISQOL and SF‐36v2® (36‐Item Short Form Health Survey, version 2). Results: Results were analyzed in 1,609 patients, including 275 in the development sample and 1,334 in the consortium sample. Response option variability patterns of all items were acceptable. Internal WISQOL consistency was acceptable. Intersample score comparisons revealed few differences. For both samples the domain‐total WISQOL score correlations exceeded 0.86. Item level analyses demonstrated suitable variation, allowing for discriminatory scoring. At the time that they completed WISQOL, patients with stones and stone related symptoms scored lowest for health related quality of life. Patients with stones but no symptoms and those with no stones scored higher. The convergent validity substudy confirmed the ability of WISQOL to identify stone specific decrements in health related quality of life that were not identified on SF‐36v2. Conclusions: WISQOL is internally consistent and discriminates among patients with different stone statuses and symptoms. WISQOL is externally valid across the North American population. It may be used for multicenter health related quality of life studies in kidney stone disease.