Jeffrey Gahan

Long-term outcomes in healthy adults after radiofrequency ablation of T1a renal tumours.

To report the long‐term oncological and renal function outcomes in healthy adults treated with radiofrequency ablation (RFA) for small renal masses.

Chemokine and Chemokine Receptor Expression in Kidney Tumors: Molecular Profiling of Histological Subtypes and Association With Metastasis

PURPOSE Molecular characterization of renal cell carcinoma may help differentiate benign oncocytoma from malignant renal cell carcinoma subtypes and predict metastasis. Chemokines, eg IL-8 and chemokine receptors such as CXCR4 and 7, promote inflammation and metastasis. SDF-1 is a CXCR4 and 7 ligand with 6 known isoforms. We evaluated the expression of these chemokines and chemokine receptors in kidney specimens. MATERIALS AND METHODS Using quantitative polymerase chain reaction we measured mRNA levels of IL-8, CXCR4 and 7, and SDF1 isoforms α, β and γ in a total of 166 specimens from 86 patients, including 86 tumor samples and 80 matched normal kidney samples. Mean ± SD followup was 18.9 ± 12 months (median 19.5). Renal cell carcinoma specimens included the clear cell, papillary and chromophobe subtype in 65, 10 and 5 cases, respectively, and oncocytoma in 6. A total of 17 cases were positive for metastasis. RESULTS Median CXCR4 and 7, and SFD1-γ levels were increased twofold to tenfold. SDF1-α and β were unchanged or lower in clear cell renal cell carcinoma and papillary tumors than in normal tissue. Median SDF1-γ, IL-8, and CXCR4 and 7 were increased threefold to fortyfold in chromophobe tumors compared to oncocytoma. CXCR4 and 7 were increased in tumors less than 4 cm (mean 3,057 ± 2,230 and 806 ± 691) compared to oncocytoma (336 ± 325 and 201 ± 281, respectively, p ≤0.016). On multivariate analysis CXCR4 (p = 0.01), CXCR7 (p = 0.02) and SDF1-β (p = 0.005) were independently associated with metastasis. Combined CXCR7 plus SDF1-α and CXCR7 plus IL-8 markers showed the highest sensitivity (71% to 81%) and specificity (75% to 80%) of all individual or combined markers. CONCLUSIONS Chemokines and chemokine receptors differentiate renal cell carcinoma and oncocytoma. Combined SDF1-α plus CXCR7 and IL-8 plus CXCR7 markers have about 80% accuracy for predicting renal cell carcinoma metastasis.

Molecular characterization of kidney cancer: Association of hyaluronic acid family with histological subtypes and metastasis

Molecular profiling of renal cell carcinomas (RCCs) may improve the distinction between oncocytoma and malignant RCC subtypes and aid in early detection of metastasis. The hyaluronic acid (HA) family includes HA synthases (HAS1, HAS2, HAS3), hyaluronidases (HYAL‐1, HYAL‐2, HYAL‐3, HYAL‐4, PH20, HYAL‐P1), and HA receptors (CD44s, CD44v, RHAMM). HA family members promote tumor growth and metastasis. The authors evaluated the expression of HA family members in kidney specimens.

The Performance of a Modified RENAL Nephrometry Score in Predicting Renal Mass Radiofrequency Ablation Success

OBJECTIVE To assess the predictive performance of a modified RENAL nephrometry score for renal tumors undergoing radiofrequency ablation (RFA). METHODS Patients who underwent RFA were identified from 2002 to 2011, and RENAL nephrometry scoring was performed for each. A modified RENAL (m-RENAL) nephrometry score was created to account for the small sizes of tumors ablated for which the size variable, R, was adjusted. A size of 3 cm was calculated as the optimal cutoff for the R component of the m-RENAL nephrometry score, and tumors were given an R score of 1 if <3 cm, 2 if 3-4 cm, or 3 if >4 cm. Other RENAL variables were unchanged. Oncologic outcomes were stratified by complexity tertiles defined as low (4-6), medium (7-9), and high (10-12). Outcomes were reported as initial ablation success (IAS), recurrence-free survival (RFS), and metastatic-free survival (MFS). The Kaplan-Meir method was used to estimate survival based on complexity tertile. RESULTS Two hundred forty patients were identified who underwent RFA, of which 192 patients were eligible for analysis. Median follow-up was 32.2 months, and median tumor size was 2.4 cm. IAS was achieved in 185 of 192 patients (96.4%). Overall, the estimated 3-year RFS was 95.1% and MFS was 97.3%. There was no statistical difference between complexity tertiles using the standard RENAL nephrometry score; however, the m-RENAL nephrometry score was significantly associated with IAS and RFS (P = .027 and P = .003, respectively). There were too few events (n = 3) to perform statistical analysis for MFS. CONCLUSION A modification to the size variable increases the performance of the RENAL nephrometry score when used to stratify RFA ablation success.

Renal tumour nephrometry score does not correlate with the risk of radiofrequency ablation complications.

To assess whether the R.E.N.A.L. nephrometry score (consists of [R]adius [tumour size as maximal diameter], [E]xophytic/endophytic properties of the tumour, [N]earness of tumour deepest portion to the collecting system or sinus, [A]nterior [a]/posterior [p] descriptor and the [L]ocation relative to the polar line) is associated with complication risk in patients that have radiofrequency ablation (RFA) for small renal masses (SRMs). To evaluate a standardised system for predicting complication risks which has not been studied.

Oncologic Efficacy of Radio Frequency Ablation for Small Renal Masses: Clear Cell vs Papillary Subtype

PURPOSE Current radio frequency ablation series do not distinguish renal cell carcinoma subtypes when reporting oncologic efficacy. Papillary neoplasms may be more amenable to radio frequency ablation than clear cell carcinoma because they are less vascular, which may limit heat energy loss. We report the long-term outcomes of patients treated with radio frequency ablation for small renal masses by renal cell carcinoma subtype. MATERIALS AND METHODS The records of patients undergoing radio frequency ablation for small renal masses (cT1a) at 2 institutions from March 2007 to July 2012 were retrospectively reviewed. Patients were included in analysis if they had biopsy confirmed clear cell or papillary renal cell carcinoma histology. Patients had at least 1 contrast enhanced cross-sectional image following radio frequency ablation. Demographic data between tumor subtypes were compared using the paired t-test. Oncologic outcomes were determined by Kaplan-Meier survival analysis and survivor curves were compared with the log rank test. RESULTS A total of 229 patients met study inclusion criteria. There were 181 clear cell tumors and 48 papillary tumors. Median followup was 33.2 months. There was no difference between tumor groups based on patient age, tumor size or grade, or months of followup. Five-year disease-free survival was 89.7% for clear cell tumors and 100% for papillary tumors (p = 0.041). There was no significant difference in overall survival (88.4% vs 89.6%, p = 0.764). CONCLUSIONS Radio frequency ablation outcomes seem to be determined in part by renal cell carcinoma subtype with clear cell renal tumors having less favorable outcomes. We hypothesize that this is due to differences in tumor vascularity. Our experience suggests that future tumor ablation studies should consider reporting outcomes based on tumor cell types.

New technologies in tumor ablation.

Purpose of review The application of ablative modalities for small renal masses continues to increase. In addition, multiple technologies continue to be studied for the treatment of these renal masses. This review focuses on new and emerging technologies so that the clinician can become more familiar with these modalities as they become available in clinical practice. Recent findings Radiofrequency ablation (RFA) and cryoablation (cryo) continue to be the most often used ablative modalities for the treatment of small renal masses. In addition, they are the most thoroughly studied modalities leading to a set of well defined variables predicting successful ablation. Microwave ablation (MWA) and irreversible electroporation are newer modalities that offer theoretical advantages to RFA and cryo, although each differs in the specific advantage provided. Multiple animal studies have been performed with each modality; however, in both cases, the optimal device settings are not well defined. For MWA in particular, there are a significant number of systems available and within each system, there are an array of variables that can be modified, which influences the ablation zone size and shape. Other emerging technologies include stereotactic body radiation and high-intensity focused ultrasound, although each has limited data supporting their efficacy to date. Summary Ablation technology continues to multiply and evolve. Newer technologies such as MWA and irreversible electroporation are promising as they offer theoretical advantages to RFA and cryo. However, both require further studies to identify the optimal tumor characteristics and device settings leading to successful ablation.

Robot-Assisted Versus Open Simple Prostatectomy for Benign Prostatic Hyperplasia in Large Glands: A Propensity Score–Matched Comparison of Perioperative and Short-Term Outcomes

OBJECTIVE To report the largest comparative analysis of robotic vs open simple prostatectomy (OSP) for large-volume prostate glands. MATERIALS AND METHODS We retrospectively reviewed 103 patients that underwent open and 64 patients that underwent robotic simple prostatectomy from 2012 to 2016 at a single institution. A propensity score-matched analysis was performed with five covariates, including age, body mass index, race, Charlson comorbidity index, and prostate volume. Perioperative, postoperative, and functional outcomes were compared between groups. RESULTS After propensity score matching there were 59 patients in each group available for comparison. There was no statistically significant difference between groups for all preoperative demographic variables. Robotic compared with OSP demonstrated a significant shorter average length of stay (LOS) (1.5 vs 2.6 days, p < 0.001), but longer mean operative time (161 vs 93 minutes, p < 0.001). The robotic approach was also associated with a lower estimated blood loss (339 vs 587 mL, p < 0.001) and lower percentage hematocrit drop (12.3% vs 19.5%, p = 0.001). Two patients required blood transfusions in the robot group compared with four in the open group, but this was not significant (p = 0.271). Improvements in maximal flow rate, International Prostate Symptom Score, quality of life, postvoid residual, and postoperative prostate-specific antigen levels were similar before and after surgery for both groups, but there was no difference between groups. There was no difference in complications between groups. CONCLUSION Robotic simple prostatectomy is a safe and effective treatment for the surgical management of benign prostatic hyperplasia. It provides similar function outcomes to the open approach; however, offers the advantage of reduced LOS and reduced blood loss.

Statin Use and Serum Lipid Levels Are Associated With Survival Outcomes After Surgery for Renal Cell Carcinoma.

OBJECTIVE To evaluate the association of statin use and preoperative serum lipid parameters with oncologic outcomes following surgery for renal cell carcinoma. METHODS A total of 850 patients who underwent surgery for localized renal cell carcinoma at our institution from 2000 to 2012 were included. Use of statins, preoperative serum lipid profile, and comprehensive clinicopathologic features were retrospectively recorded. Kaplan-Meier analysis and multivariate Cox proportional hazards model were employed to compare survival outcomes. RESULTS There were 342 statin users and 508 non-users. Median follow-up was 25.0 months. Statin users were older, had greater body mass index, and had worse performance status than non-users. Tumor pathologic characteristics were balanced between groups. Five-year recurrence free survival (RFS) was 77.9% for non-users compared with 87.6% for statin users (P = .004). After adjustment for clinicopathologic variables, statin use was independently associated with improved RFS (hazard ratio [HR] 0.54, 95% confidence interval [CI] 0.33-0.86, P = .011) and overall survival (HR 0.45, 95%CI 0.28-0.71, P = .001). In patients with available serum lipid parameters (n = 193), 5-year RFS was 83.8% for patients with triglycerides <250 mg/dL compared with 33.3% for those with triglycerides >250 mg/dL (P <.0001). Elevated serum triglycerides (>250 mg/dL) was independently associated with worse RFS (HR 2.69, 95%CI 1.22-5.93, P = .015) on multivariate analysis. CONCLUSION Statin use was independently associated with improved survival, whereas elevated serum triglyceride levels correlated with worse oncologic outcomes in this cohort. These findings warrant validation in prospective studies.

Equivocal Ureteropelvic Junction Obstruction on Diuretic Renogram—Should Minimally Invasive Pyeloplasty be Offered to Symptomatic Patients?

PURPOSE Equivocal ureteropelvic junction obstruction refers to clinical symptoms and/or other radiological suggestions of possible ureteropelvic junction obstruction but with inconclusive results of obstruction on diuretic renogram. We evaluated long-term outcomes in patients with equivocal ureteropelvic junction obstruction treated with minimally invasive pyeloplasty. MATERIALS AND METHODS We retrospectively analyzed the records of 125 consecutive patients who underwent minimally invasive pyeloplasty as performed by a single surgeon from May 2004 to July 2013. Of 98 patients with followup those with more than 6-month followup were included in analysis. Equivocal ureteropelvic junction obstruction, defined as half-life less than 20 minutes on diuretic renogram, was identified in 23 patients. All patients underwent transperitoneal minimally invasive pyeloplasty. We evaluated patient demographics, preoperative and postoperative symptoms and renal function. RESULTS The 16 female and 7 male patients with equivocal ureteropelvic junction obstruction had flank pain and associated hydronephrosis on imaging. At a median followup of 20.2 months (range 7 to 75) 95.7% of patients with equivocal obstruction achieved complete symptom resolution. Mean ± SD preoperative and postoperative half-life was 14.1 ± 3.7 and 7.4 ± 4.2 minutes, respectively, for an improvement of 6.7 minutes (p < 0.001). In 1 patient (4.3%) with equivocal obstruction of a complicated iatrogenic etiology treatment ultimately failed postoperatively and endopyelotomy was required. There was no statistically significant difference in clinical or radiological success between the equivocal obstruction group and the 75 patients treated with minimally invasive pyeloplasty for definitive ureteropelvic junction obstruction (p = 0.44 and 0.07, respectively). CONCLUSIONS In patients with radiographic equivocal ureteropelvic junction obstruction and flank pain minimally invasive pyeloplasty efficaciously provides symptomatic relief and functional preservation. Results are comparable to those in patients with high grade obstruction.