Ercan Malkoc

Predictors of Excisional Volume Loss in Partial Nephrectomy: Is There Still Room for Improvement?

UNLABELLED Since volume loss is the most important modifiable determinant of long-term renal function after partial nephrectomy, there is great interest in ways to reduce the loss of healthy parenchyma. We retrospectively reviewed 880 partial nephrectomies to identify predictors of excisional volume loss (EVL), based on pathologic assessment. After stepwise variable selection, we assessed age, sex, solitary kidney status, tumor size, endophytic property, estimated blood loss, surgical approach, and surgeon volume for association with EVL using multiple regression. Male sex (p<0.01), larger tumors (p<0.01), endophytic tumors (p=0.01), open approach (p<0.01), increased bleeding (p<0.01), and higher surgeon volume (p<0.01) were independently associated with greater EVL. Approach strongly influenced EVL with open surgery having 7.8 cm(3) more EVL than robotic surgery. Negative surgical margins (95.7% vs 94.1%, p=0.32) did not differ between open and robotic approaches, respectively. EVL is associated with patient, tumor, and especially provider factors, suggesting that volume preservation may be improved with surgical optimization. Lack of percent volume loss data, which precluded assessment of EVLs impact on long-term renal function, is a limitation. PATIENT SUMMARY We found that surgical approach affects the quantity of healthy kidney removed during cancer surgery, suggesting that there is room for further surgical improvement.

Excisional Precision Matters: Understanding the Influence of Excisional Volume Loss on Renal Function After Partial Nephrectomy

Renal function after partial nephrectomy (PN) may depend on modifiable factors including ischemia time, excision of healthy parenchyma (excisional volume loss, EVL), and reconstructive methods. We retrospectively reviewed our institutional robotic PN database to identify the predictors of glomerular filtration rate (GFR) preservation (GFR-P) at 3-12 mo postoperatively, during which GFR decline plateaus. Baseline clinical, sociodemographic, and radiologic characteristics were captured. Univariate and multivariate (MV) linear regression analyses were performed and marginal effects were employed to examine the relative effect of EVL on renal function. A total of 647 patients who underwent robotic PN had GFR data at a median follow-up of 6 mo. On MV models, EVL was significantly correlated with GFR-P following log transformation (p=0.001). Each doubling of EVL caused a 1.5% decrease in GFR-P. Ischemia time and tumor complexity were not significantly associated with GFR-P. In summary, GFR-P after PN appears to be significantly associated with the excised volume of benign parenchyma. PATIENT SUMMARY At a high-volume tertiary care center, we investigated the impact of surgical factors on kidney function after kidney cancer surgery. We found that the surgical precision with which the tumor is excised significantly impacts kidney function at 3-12 mo after surgery.

Testis-Sparing Surgery in Small Testicular Masses Not Suspected to Be Malignant

UNLABELLED Fifteen patients with small testicular masses not suspected to be malignant were included in the study, and permanent and frozen section analyses were evaluated. As a result frozen analysis, preoperative externalization of the suspected malignancy with a physical examination, ultrasonographic evaluation, and serum tumor marker analysis were concluded as key points for accurate decision making between TSS and radical orchiectomy. BACKGROUND We aimed to determine the safety, efficacy, and the concordance of permanent and frozen section analysis (FSA) of testis-sparing surgery (TSS) in patients who had small testicular masses that were not suspected to be malignant. PATIENTS AND METHODS Fifteen patients who underwent TSS were included in the study. TSS was performed for the patients who had testicular lesions <25 mm and testicular lesion volume <30% of the whole testis. All patients had normal serum tumor marker levels and ultrasonographic evaluation did not indicate malignancy. Surgery was performed via an inguinal approach with temporary cord occlusion and FSA of the lesions. Benign findings allowed for TSS, and cancer prompted total orchiectomy. RESULTS The mean patient age was 25.33 (range, 20-36) years. The predominant complaint was swelling (9 patients). The mean lesion diameter was 16 mm (range, 5-26 mm). Fourteen of all cases (93%) had benign pathology and underwent TSS. Only 1 patient, whose FSA revealed malignant formation, underwent radical orchiectomy. Final pathology of this patient was seminoma. Complete histopathologic concordance was observed between the results of frozen and permanent sections. TSS was performed with no intra- or postoperative complications. After a mean follow-up of 23 months (range, 6-44 months) all patients, except 3 who were lost to follow-up, were free of disease. CONCLUSION The main key points for accurate decision-making between TSS and radical orchiectomy are intraoperative FSA and preoperative externalization of possible suspected malignancy with physical examination, ultrasonographic evaluation, and serum tumor marker analysis.

Comparison of robot-assisted and open partial nephrectomy for completely endophytic renal tumours: a single centre experience.

To compare outcomes between robot‐assisted partial nephrectomy (RAPN) and open PN (OPN) for completely endophytic renal tumours.

Free Nerve Ending Density on Skin Extracted by Circumcision and Its Relation to Premature Ejaculation

Many studies have shown that skin tissue extracted by circumcision can cause differences in sexual function, especially at the time of ejaculation. Sensitivity changes in penile skin and sexual satisfaction deriving from circumcision starting from premature ejaculation (PE) are discussed. Furthermore, most of these studies rely on questionnaires. Extracted free nerve endings (FNE) on the foreskin, which can detect temperature, mechanical stimuli (touch, pressure, stretch) or pain (nociception), have not been researched. Our aim is to determine FNEs in foreskin and the affects on sexual function, especially PE. This prospective study was done on adults who voluntarily applied to be circumcised between September 2010 and October 2011. The ejaculation latency times (ELT) before circumcision have been assessed, and a PE diagnostic tool (PEDT) form was filled out by the urologist according to the answers given by the volunteers. The proximal and distal ends of the foreskin were marked before circumcision, and the extracted foreskin was sent to the pathology department to determine FNEs. Twenty volunteers (average age 21.25 ± 0.44 years) were included in the study. The average ELT was 103.55 ± 68.39 seconds, and the average PE score was 4.35 ± 3.13. Proximal, middle, and distal tip nerve densities were compared. Proximal and distal (P = .003) and proximal and middle (P = .011) segments differed from each other, whereas middle and distal were similar (P = .119). There were not any correlations between PEDT scores and total nerve endings number (r = .018, P = .942). Also there were not any correlations between mean ELT and PEDT scores (r = .054, P = .822). The tissue extracted by circumcision has intensive FNEs, yet FNE intensity has no relation to PE.

When Partial Nephrectomy is Unsuccessful: Understanding the Reasons for Conversion from Robotic Partial to Radical Nephrectomy at a Tertiary Referral Center

Purpose: We sought to identify the preoperative factors associated with conversion from robotic partial nephrectomy to radical nephrectomy. We report the incidence of this event. Materials and Methods: Using our institutional review board approved database, we abstracted data on 1,023 robotic partial nephrectomies performed at our center between 2010 and 2015. Standard and converted cases were compared in terms of patients and tumor characteristics, and perioperative, functional and oncologic outcomes. Logistic regression analysis was done to identify predictors of radical conversion. Results: The overall conversion rate was 3.1% (32 of 1,023 cases). The most common reasons for conversion were tumor involvement of hilar structures (8 cases or 25%), failure to achieve negative margins on frozen section (7 or 21.8%), suspicion of advanced disease (5 or 15.6%) and failure to progress (5 or 15.6%). Patients requiring conversion were older and had a higher Charlson score (both p <0.01), including an increased prevalence of chronic kidney disease (p = 0.02). Increasing tumor size (5 vs 3.1 cm, p <0.01) and R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, location relative to polar lines and hilar location) score (9 vs 8, p <0.01) were also associated with an increased risk of conversion. Worse baseline renal function (OR 0.98, 95% CI 0.96–0.99, p = 0.04), large tumor size (OR 1.44, 95% CI 1.22–1.7, p <0.01) and increasing R.E.N.A.L. score (p = 0.02) were independent predictors of conversion. Compared to converted cases, at latest followup standard robotic partial nephrectomy cases had similar short‐term oncologic outcomes but better renal functional preservation (p <0.01). Conclusions: At a high volume center the rate of robotic partial nephrectomy conversion to radical nephrectomy was 3.1%, including 2.2% of preoperatively anticipated nephrectomy cases. Increasing tumor size and complexity, and poor preoperative renal function are the main predictors of conversion.

Perioperative morbidity, oncological outcomes and predictors of pT3a upstaging for patients undergoing partial nephrectomy for cT1 tumors

ObjectivesTo evaluate perioperative morbidity, oncological outcome and predictors of pT3a upstaging after partial nephrectomy (PN).Materials and methodsRetrospective study of 1042 patients who underwent PN for cT1N0M0 renal cell carcinoma between 2007 and 2015. A total of 113 cT1 patients were upstaged to pT3a, while 929 were staged as pT1. Demographic, perioperative and pathological variables were reviewed. We compared the clinico-pathological characteristics, perioperative morbidity and oncological outcomes between pT3a and pT1 groups. Multivariate regression evaluates variables associated with T3a upstaging. Recurrence-free survival (RFS) and overall survival analyses were performed. Survival curves were compared using log-rank test.ResultsThe pT3a tumors were high complexity tumors (median RENAL score 8 vs. 7, p < 0.01), higher hilar (h) location (27.5 vs. 14.8%, p < 0.01), higher grade (57.5 vs. 38.2%, p < 0.01), and higher positive surgical margins (18.6 vs. 5.8%, p < 0.01. Patients with pT3a had a higher estimated blood loss, transfusion rate, ischemia time and overall complications, though there were no differences in median e-GFR decline and major (Grade III-V) complications. Five-year RFS was 78.5% for pT3a group vs. 94.6% for pT1 group (log-rank p < 0.01). Male gender (OR 2.2, p < 0.01), and R.E.N.A.L. score (OR 2.3, p = 0.01) were preoperative predictors of upstaging. We acknowledge limitations in our study, most are inherent problems of retrospective studies.ConclusionPerioperative morbidity, after partial nephrectomy, is acceptable in cT1/pT3 tumors in comparison to cT1/pT1; however, upstaged patients had a worse oncological outcome. cT1/pT3a tumors are associated with adverse clinico-pathological features. Preoperative risk predictors of upstaging were higher R.E.N.A.L. score and male gender.

Patterns and Predictors of Recurrence after Partial Nephrectomy for Kidney Tumors

Purpose: We sought to identify patterns and predictors of recurrence in patients with clinically localized renal cell carcinoma managed by partial nephrectomy. Materials and Methods: We performed a retrospective study of 830 consecutive cases of partial nephrectomy done between 2007 and 2015 for clinically localized renal cell carcinoma at a single institution. Patient demographics and pathological characteristics were correlated with recurrence patterns (overall, local and distant) and overall survival using Kaplan‐Meier and Cox regression analyses. Differences in the recurrence patterns were evaluated. Results: Median patient age was 61 years and median tumor size was 3.1 cm. Overall, 11.6% of tumors were stage pT3, 39.3% were high grade, 2.9% had lymphovascular invasion and 7.1% had positive margins. Higher grade, higher stage, positive surgical margins and increased R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of deepest tumor portion to collecting system or sinus, anterior/posterior and location relative to polar line) score were associated with shorter disease‐free survival on Kaplan‐Meier analysis. On multivariable regression pT (p <0.01), grade (p <0.01) and R.E.N.A.L. score (p = 0.03) remained independent predictors of disease‐free survival. Predictors of metastasis were pT stage (HR 4.5) and grade (HR 3.9, both p <0.01), while R.E.N.A.L. score (HR 3.2, p = 0.03) was the single predictor of local recurrence. Five‐year disease‐free and overall survival probabilities were 91% and 94%, respectively. Local recurrence manifested and developed earlier than metastasis (median 13 vs 22 months, p <0.01). Conclusions: High pT stage, high grade and high R.E.N.A.L. score increase the risk of disease recurrence after partial nephrectomy. The pT stage and grade are predictors of metastasis, while R.E.N.A.L. score predicts local recurrence. Because relapse features and risk factors differ between the 2 recurrence patterns, they should be studied separately in the future.

Robot-assisted approach improves surgical outcomes in obese patients undergoing partial nephrectomy

To assess the impact of approach on surgical outcomes in otherwise healthy obese patients undergoing partial nephrectomy for small renal masses.

External validation of a PCA-3-based nomogram for predicting prostate cancer and high-grade cancer on initial prostate biopsy

The aim of this study was to externally validate a previously developed PCA3‐based nomogram for the prediction of prostate cancer (PCa) and high‐grade (intermediate and/or high‐grade) prostate cancer (HGPCa) at the time of initial prostate biopsy.