Comparison of Race-Based and Non-Race-Based Glomerular Filtration Rate Equations for the Assessment of Renal Functional Risk Before Nephrectomy.

OBJECTIVE: To compare the performance of race-based and race-neutral estimated glomerular filtration rate (eGFR) calculators in patients undergoing kidney surgery. METHODS: Analysis of institutional kidneys surgeries from 2006-2021 was conducted. Demographics, serum creatinine (SCr), protein dipstick, and creatinine clearance (CrCl) were assessed within 1 week prior to surgery. SCr was used to calculate eGFR using 3 models: Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI 2009), and CKD-EPI 2021. Patients were classified based on Kidney Disease: Improving Global Outcomes (KDIGO) criteria for CKD staging and prognosis, with urine CrCl treated as benchmark for analysis. Receiver operating characteristic (ROC) analysis evaluated accuracy of eGFR calculators' binary discrimination of eGFR less than 60 mL/min. CKD stage agreement between eGFR and urine CrCl was assessed. RESULTS: A total of 554 kidney surgeries in 336 patients had necessary laboratory data for analysis. The cohort was 62% male, with a median age of 47. Within this cohort, 8.1% (n=45) were Black, and 80% (n=441) were White. glomerular filtration rate (GFR) from 24-hour urine CrCl normalized by BSA did not vary significantly from eGFR by SCr based calculators. The proportion of patients with eGFR <60 significantly differed when using Modification of Diet in Renal Disease, CKD-EPI 2009, and CKD-EPI 2021 equations when compared to CrCl (P<.001). Still, they performed equivalently in the staging of CKD, as well as in predicting GFR of less than 60, and classifying CKD prognosis of "moderately increased or higher". CONCLUSION: A race-neutral eGFR calculator can perform equivalently to established eGFR calculators, with the added benefit of mitigating biases that account for racial disparities in nephrectomy decision making.

The role of novel imaging in prostate cancer focal therapy: treatment and follow-up.

PURPOSE OF REVIEW: Multiparametric magnetic resonance imaging (mpMRI) has fundamentally changed how intraprostatic lesions are visualized, serving as a highly sensitive means for detecting clinically significant prostate cancer (csPCa) via image-targeted biopsy. However, limitations associated with mpMRI have led to the development of new imaging technologies with the goal of better characterizing intraprostatic disease burden to more accurately guide treatment planning and surveillance for prostate cancer focal therapy. Herein, we review several novel imaging modalities with an emphasis on clinical data reported within the past two years. RECENT FINDINGS: 7T MRI, artificial intelligence applied to mpMRI, positron emission tomography combined with either computerized tomography or MRI, contrast-enhanced ultrasound, and micro-ultrasound are novel imaging modalities with the potential to further improve intraprostatic lesion localization for applications in focal therapy for prostate cancer. Many of these technologies have demonstrated equivalent or favorable diagnostic accuracy compared to contemporary mpMRI for identifying csPCa and some have even shown improved capabilities to define lesion borders, to provide volumetric estimates of lesions, and to assess the adequacy of focal ablation of planned treatment zones. SUMMARY: Novel imaging modalities with capabilities to better characterize intraprostatic lesions have the potential to improve accuracy in treatment planning, real-time assessment of the ablation zone, and posttreatment surveillance; however, many of these technologies require further validation to determine their clinical utility.

Initial experience and cancer detection rates of office-based transperineal magnetic resonance imaging-ultrasound fusion prostate biopsy under local anesthesia.

INTRODUCTION: We aimed to demonstrate feasibility and cancer detection rates of office-based ultrasound-guided transperineal magnetic resonance imaging-ultrasound (MRI-US) fusion (TFB) prostate biopsy under local anesthesia. METHODS: With institutional review board approval, records of men undergoing TFB in the office setting under local anesthesia were reviewed. Baseline patient characteristics, MRI findings, cancer detection rates, and complications were recorded. The PrecisionPoint Transperineal Access System (Perineologic, Cumberland, MD, U.S.), along with UroNav 3.0 image-fusion system (Invivo International, Best, The Netherlands) were used for all procedures. Following biopsy, men were surveyed to assess patient experience. RESULTS: Between January 2019 and February 2020, 200 TFBs were performed, of which 141 (71%) were positive for prostate cancer, with 117 (83%) Gleason grade group 2 or higher. A total of 259 of 265 MRI lesions were biopsied, with 127 (49%) positive overall. Prostate Imaging-Reporting and Data System (PI-RADS) 4-5 lesions were positive for prostate cancer in 59% of cases. The mean procedural time was 20 minutes, with a patient enter-to-exit room time of 54 minutes. There were no septic complications, no patients required post-procedure hospital admission, and all procedures were successfully completed. Seventy-five percent of patients surveyed reported complete resolution of pain at three days following the procedure. CONCLUSIONS: Office-based TFB represents a viable approach to prostate cancer detection following prostate MRI. Larger-scale assessment is needed to categorize cancer detection rates more accurately by PI-RADs subset, patient selection factors, complication rate, and cost relative to TFB under anesthesia.

Feasibility and Utility of Mobile Applications for the Evaluation of Urology Residents' Surgical Competence.

OBJECTIVE: To provide real-time assessment and feedback on the competency of urology residents' surgical skill via mobile applications and examine their feasibility and utility. MATERIALS AND METHODS: Two mobile application-based systems (SIMPL and myTIPreport) were sequentially implemented for the case-by-case assessment of residents' performance of surgical skills at a single institution. Data was collected regarding residents' perception of their feedback pre- and post-implementation of the applications. Faculty were surveyed after their implementation to determine their feasibility and utility. RESULTS: 297 individual evaluations were completed with SIMPL and 822 with myTIPreport over four and eleven months respectively. Post-implementation, residents showed significantly improved perceptions regarding the quantity and personalization of surgical skill feedback (P = .043 and .005 respectively). A majority (75%) of the faculty found the mobile applications feasible to use, an improvement compared to prior methods of resident evaluation, and would recommend continued use. CONCLUSION: This study represents the first documented use of real-time surgical competency assessment in urology. The use of mobile applications to evaluate urology residents' surgical competency in clinical practice is both feasible and useful. Their use may allow for more individualized surgical skill teaching during training and for the verification of the surgical skills necessary to practice autonomously.

In-Hospital 30-Day Survival Among Young Adults With Coronavirus Disease 2019: A Cohort Study.

BACKGROUND: Our objective was to characterize young adult patients hospitalized with coronavirus disease 2019 (COVID-19) and identify predictors of survival at 30 days. METHODS: This retrospective cohort study took place at 12 acute care hospitals in the New York City area. Patients aged 18-39 hospitalized with confirmed COVID-19 between March 1 and April 27, 2020 were included in the study. Demographic, clinical, and outcome data were extracted from electronic health record reports. RESULTS: A total of 1013 patients were included in the study (median age, 33 years; interquartile range [IQR], 28-36; 52% female). At the study end point, 940 (92.8%) patients were discharged alive, 18 (1.8%) remained hospitalized, 5 (0.5%) were transferred to another acute care facility, and 50 (4.9%) died. The most common comorbidities in hospitalized young adult patients were obesity (51.2%), diabetes mellitus (14.8%), and hypertension (13%). Multivariable analysis revealed that obesity (adjusted hazard ratio [aHR], 2.71; 95% confidence interval [CI], 1.28-5.73; P = .002) and Charlson comorbidity index score (aHR, 1.20; 95% CI, 1.07-1.35; P = .002) were independent predictors of in-hospital 30-day mortality. CONCLUSIONS: Obesity was identified as the strongest negative predictor of 30-day in-hospital survival in young adults with COVID-19.

Prognostic Molecular Signatures for Metastatic Potential in Clinically Low-Risk Stage I and II Clear Cell Renal Cell Carcinomas.

Introduction: For patients with localized node-negative (Stage I and II) clear cell renal cell carcinomas (ccRCC), current clinicopathological staging has limited predictive capability because of their low risk. Analyzing molecular signatures at the time of nephrectomy can aid in understanding future metastatic potential. Objective: Develop a molecular signature that can stratify patients who have clinically low risk ccRCC, but have high risk genetic changes driving an aggressive metastatic phenotype. Patients, Materials, and Methods: Presented is the differential expression of mRNA and miRNA in 44 Stage I and Stage II patients, 21 who developed metastasis within 5 years of nephrectomy, compared to 23 patients who remained disease free for more than 5 years. Extracted RNA from nephrectomy specimens preserved in FFPE blocks was sequenced using RNAseq. MiRNA expression was performed using the TaqMan OpenArray qPCR protocol. Results: One hundred thirty one genes and 2 miRNA were differentially expressed between the two groups. Canonical correlation (CC) analysis was applied and four CCs (CC32, CC20, CC9, and CC7) have an AUC > 0.65 in our dataset with similar predictive power in the TCGA-KIRC dataset. Gene set enrichment showed CC9 as kidney development/adhesion, CC20 as oxidative phosphorylation pathway, CC32 as RNA binding/spindle and CC7 as immune response. In a multivariate Cox model, the four CCs were able to identify high/low risk groups for metastases in the TCGA-KIRC (p < 0.05) with odds ratios of CC32 = 5.7, CC20 = 4.4, CC9 = 3.6, and CC7 = 2.7. Conclusion: These results identify molecular signatures for more aggressive tumors in clinically low risk ccRCC patients who have a higher potential of metastasis than would be expected.

Primary renal Ewing Sarcoma masquerading as Wilms in an adolescent female.

Primary renal Ewing's sarcoma (ES) of the kidney represents a rare oncologic entity belonging to the collection of small round cell tumors, which typically feature osseous presentations. Renal ES is an aggressive disease entity with high metastatic potential, either at time of presentation or following initial extirpative therapy. Herein, we report the case of a 14-year-old female who initially presented with intermittent gross painless hematuria and a large left renal mass identified on ultrasound and confirmed on follow up MRI. Following partial nephrectomy (PN), patient was diagnosed with primary renal ES and subsequently underwent completion nephrectomy and chemotherapy.

Presenting Characteristics, Comorbidities, and Outcomes Among 5700 Patients Hospitalized With COVID-19 in the New York City Area.

Importance: There is limited information describing the presenting characteristics and outcomes of US patients requiring hospitalization for coronavirus disease 2019 (COVID-19). Objective: To describe the clinical characteristics and outcomes of patients with COVID-19 hospitalized in a US health care system. Design, Setting, and Participants: Case series of patients with COVID-19 admitted to 12 hospitals in New York City, Long Island, and Westchester County, New York, within the Northwell Health system. The study included all sequentially hospitalized patients between March 1, 2020, and April 4, 2020, inclusive of these dates. Exposures: Confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by positive result on polymerase chain reaction testing of a nasopharyngeal sample among patients requiring admission. Main Outcomes and Measures: Clinical outcomes during hospitalization, such as invasive mechanical ventilation, kidney replacement therapy, and death. Demographics, baseline comorbidities, presenting vital signs, and test results were also collected. Results: A total of 5700 patients were included (median age, 63 years [interquartile range {IQR}, 52-75; range, 0-107 years]; 39.7% female). The most common comorbidities were hypertension (3026; 56.6%), obesity (1737; 41.7%), and diabetes (1808; 33.8%). At triage, 30.7% of patients were febrile, 17.3% had a respiratory rate greater than 24 breaths/min, and 27.8% received supplemental oxygen. The rate of respiratory virus co-infection was 2.1%. Outcomes were assessed for 2634 patients who were discharged or had died at the study end point. During hospitalization, 373 patients (14.2%) (median age, 68 years [IQR, 56-78]; 33.5% female) were treated in the intensive care unit care, 320 (12.2%) received invasive mechanical ventilation, 81 (3.2%) were treated with kidney replacement therapy, and 553 (21%) died. As of April 4, 2020, for patients requiring mechanical ventilation (n = 1151, 20.2%), 38 (3.3%) were discharged alive, 282 (24.5%) died, and 831 (72.2%) remained in hospital. The median postdischarge follow-up time was 4.4 days (IQR, 2.2-9.3). A total of 45 patients (2.2%) were readmitted during the study period. The median time to readmission was 3 days (IQR, 1.0-4.5) for readmitted patients. Among the 3066 patients who remained hospitalized at the final study follow-up date (median age, 65 years [IQR, 54-75]), the median follow-up at time of censoring was 4.5 days (IQR, 2.4-8.1). Conclusions and Relevance: This case series provides characteristics and early outcomes of sequentially hospitalized patients with confirmed COVID-19 in the New York City area.

Management and treatment options when facing malignant ureteral obstruction.

Malignant ureteral obstruction is an unfortunate finding that can be caused by a wide-ranging number of malignancies with a prognosis of limited survival. Given its presentation and progression, it can be refractory to treatment by traditional single polymeric ureteral stents. With a higher failure rate than causes of benign ureteral obstruction, a number of other options are available for initial management, as well as in cases of first-line therapy failure, including tandem stents, metallic stents, percutaneous nephrostomies and extra-anatomic stents. We reviewed the literature and carried out a PubMed search including the following keywords and phrases: "malignant ureteral obstruction," "tandem ureteral stents," "metallic ureteral stents," "resonance stent," "metal mesh ureteral stents" and "extra-anatomic stents." The vast majority of studies were small and retrospective, with a large number of studies related to metallic stents. Given the heterogenous patient population and diversity of practice, it is difficult to truly assess the efficacy of each method. As there are no guidelines or major head-to-head prospective trials involving these techniques, it makes practicing up to the specific provider. However, this article attempts to provide a framework with which the urologist who is presented with malignant ureteral obstruction can plan in order to provide the individualized care on a case-by-case basis. What is clear is that prospective, randomized clinical trials are necessary to help bring evidence-based medicine and guidelines for patients with malignant ureteral obstruction.

High Prevalence of Erythrasma in Patients with Inverse Psoriasis: A Cross-sectional Study.

BACKGROUND: Inverse psoriasis is characterized by erythematous nonscaly plaques in intertriginous regions. Similarly, erythrasma, a superficial infection caused by Corynebacterium minutissimum (C. minutissimum), is also found in skin folds with red-brown lesions, making the distinction between psoriasis and erythrasma difficult. No studies have previously determined whether these two clinically similar cutaneous disorders can occur concurrently. METHODS: Thirty patients with inverse psoriatic plaques were examined using a standard Wood's lamp to visualize porphyrins associated with C. minutissimum. RESULTS: Just over half (56.6%) of patients with inverse psoriatic plaques showed evidence of this bacterium. Specifically, 45.5 percent of inverse psoriatic lesions were found to be positive for C. minutissimum, with the highest prevalence of erythrasma located in the gluteal cleft. CONCLUSION: Clinical suspicion for C. minutissimum should be high in patients with inverse psoriasis due to the organism's potential to trigger or exacerbate psoriatic lesions. Further studies are indicated to determine the response to treatment in patients with this combination.

Conservative Management of Liver Perforation During Percutaneous Nephrolithotomy: Case Couplet Presentation.

Percutaneous nephrolithotomy (PCNL) remains the recommended intervention for large kidney stones, major complications, although rare, are between 1% and 7%. Literature regarding liver injury during PCNL is sparse, and many incidences occur unnoticed. In general, most liver injuries can be treated conservatively when compared with other organ injury sustained during PCNL. Despite this, there is still significant potential for intraperitoneal bleeding as well as possible hemodynamic instability that may result secondary to the inadvertent access. Our team describes two cases of liver injury during PCNL with focus on presentation and injury management. Both cases were treated conservatively through close clinical monitoring and delayed removal of nephrostomy tube. Both liver injuries were diagnosed primarily through postprocedure axial CT imaging. In general, risk factors include supracostal access, particularly at or above the 11th rib, as well as hepatomegaly. Despite that liver injury is a rare complication of right-sided PCNL, outcomes can result in significant blood loss not diagnosed. We present in this study two instances of effective conservative management of liver injury after PCNL.

Management of Splenic Injury During Percutaneous Nephrolithotomy: Report of Two Cases.

Percutaneous nephrolithotomy (PCNL) has become the standard of care for the removal of kidney stones >2 cm. Major complications, although rare, are between 1% and 7%. Splenic injury during PCNL is rare and can often be managed conservatively, but has the potential to be devastating, necessitating the importance of early diagnosis. Our team describes two cases of splenic injury during PCNL with emphasis on diagnosis and management. Although both cases were managed conservatively through close monitoring and prolonged nephrostomy tube presence, one case had a concurrent pneumothorax. Both cases were diagnosed primarily through postprocedure CT imaging. Risk factors primarily include supracostal access and splenomegaly. Splenic injury is a rare complication that can often be managed conservatively; however, prompt recognition of injury is important. We present in this study two cases of conservative splenic injury management sustained during PCNL.

Management of Colon Perforation During Percutaneous Nephrolithotomy in Patients with Complex Anatomy: A Case Series.

Percutaneous nephrolithotomy (PCNL), first described in 1976, is the gold standard for the management of large kidney stones, with stone-free rates as high as 95% in contemporary literature. Colonic injuries during PCNL are a rare complication with an estimated incidence of 0.3%-0.5%. However, given the high morbidity incurred and the necessity of prompt operative intervention, it is imperative that practitioners have a low suspicion threshold for such injuries, particularly in those patients with altered or complex anatomy. This case series addresses peri- and postoperative outcomes of colon perforation during PCNL in patients with complex anatomy and reviews the technical challenges of surgery with potential methods to avoid injury in the future. Herein we review three instances of colonic injuries and their subsequent management to highlight both the presentation and the optimal management of these rare occurrences.

Implementation of multiparametric magnetic resonance imaging technology for evaluation of patients with suspicion for prostate cancer in the clinical practice setting.

OBJECTIVES: To investigate the impact of implementing magnetic resonance imaging (MRI) and ultrasonography fusion technology on biopsy and prostate cancer (PCa) detection rates in men presenting with clinical suspicion for PCa in the clinical practice setting. PATIENTS AND METHODS: We performed a review of 1 808 consecutive men referred for elevated prostate-specific antigen (PSA) level between 2011 and 2014. The study population was divided into two groups based on whether MRI was used as a risk stratification tool. Univariable and multivariable analyses of biopsy rates and overall and clinically significant PCa detection rates between groups were performed. RESULTS: The MRI and PSA-only groups consisted of 1 020 and 788 patients, respectively. A total of 465 patients (45.6%) in the MRI group and 442 (56.1%) in the PSA-only group underwent biopsy, corresponding to an 18.7% decrease in the proportion of patients receiving biopsy in the MRI group (P < 0.001). Overall PCa (56.8% vs 40.7%; P < 0.001) and clinically significant PCa detection (47.3% vs 31.0%; P < 0.001) was significantly higher in the MRI vs the PSA-only group. In logistic regression analyses, the odds of overall PCa detection (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.29-2.35; P < 0.001) and clinically significant PCa detection (OR 2.04, 95% CI 1.48-2.80; P < 0.001) were higher in the MRI than in the PSA-only group after adjusting for clinically relevant PCa variables. CONCLUSION: Among men presenting with clinical suspicion for PCa, addition of MRI increases detection of clinically significant cancers while reducing prostate biopsy rates when implemented in a clinical practice setting.

Laparoscopic Completion Nephrectomy for Local Surgical Bed Recurrence After Partial Nephrectomy: An Analysis of Procedural Complexity and Feasibility.

OBJECTIVES: To study the feasibility and perioperative outcomes associated with a laparoscopic approach to completion nephrectomy in patients with locoregional disease recurrence after partial nephrectomy (PN) for renal cell carcinoma. PATIENTS AND METHODS: We performed a retrospective review of patients who underwent PN between 2006 and 2016 and developed locoregional recurrence, defined by the presence of new disease within the original surgical bed. Those undergoing planned laparoscopic completion nephrectomy constituted the study cohort. Perioperative outcomes as well as clinical and pathologic parameters associated with ability to effectively perform laparoscopic completion nephrectomy were assessed. RESULTS: Among 1259 patients who underwent PN during the study period, 45 cases (3.6%) of locoregional disease recurrence were observed. A laparoscopic approach to completion nephrectomy was attempted in 33 patients. Overall, 16 (48.5%) patients experienced a postoperative complication, 9 of whom (27.3%) had a major event (Clavien grade ≥3). Intraoperative open conversion was necessary in 12 (36%) patients. Higher R.E.N.A.L score of the original tumor (p < 0.001) and clinical evidence of synchronous metastatic relapse (p < 0.001) were associated with increased likelihood of open conversion. Blood loss (725 mL vs 175 mL, p < 0.001), operative time (280 minutes vs 160 minutes, p < 0.001), risk of major postoperative complication (58% vs 9.5%, p = 0.005), and hospital length of stay (4.5 days vs 2 days, p = 0.026) were significantly higher in individuals requiring open conversion. CONCLUSION: Laparoscopic completion nephrectomy for true locoregional recurrence is a technically demanding procedure associated with significant postoperative morbidity and a high rate of open conversion. Although feasible, careful patient selection may optimize surgical outcomes.

Robotic surgery in pediatric urology.

While robotic surgery has shown clear utility and advantages in the adult population, its role in pediatrics remains controversial. Pediatric-sized robotic instruments and equipment are not readily available yet, so certain modifications can be made in order to make robotic surgery successful in children. While the cost of robotic surgery remains high compared to open procedures, patients experience greater satisfaction and quality of life with robotic surgery. Robotic pyeloplasty is a standard of care in older children, and has even been performed in infants and re-do surgery. Other robotic procedures performed in children include heminephroureterectomy, ureteroureterostomy, ureteral reimplantation, urachal cyst excision, bladder diverticulectomy, and bladder reconstructive procedures such as augmentation, appendicovesicostomy, antegrade continence enema, bladder neck reconstruction and sling, as well as other procedures. Robotic surgery has also been used in oncologic cases such as partial nephrectomy and retroperitoneal lymph node dissection. Future improvements in technology with production of pediatric-sized robotic instruments, along with increases in robotic-trained pediatric urologists and surgeon experience along each's learning curve, will help to further advance the field of robotic surgery in pediatric urology.

Partial Nephrectomy is Associated with Higher Risk of Relapse Compared with Radical Nephrectomy for Clinical Stage T1 Renal Cell Carcinoma Pathologically Up Staged to T3a.

PURPOSE: We studied recurrence-free survival after partial vs radical nephrectomy for clinical stage T1 renal cell carcinoma in all patients and in those up staged to pathological stage T3a. MATERIALS AND METHODS: We retrospectively reviewed the records of 1,250 patients who underwent partial or radical nephrectomy for clinically localized T1 renal cell carcinoma between 2006 and 2014. Recurrence-free survival was estimated using the Kaplan-Meier method and evaluated as a function of nephrectomy type with the log rank test and Cox models, adjusting for clinical, radiological and pathological characteristics. RESULTS: A total of 86 recurrences (7%) were observed during a median followup of 37 months. No difference in recurrence-free survival between partial and radical nephrectomy was found among all clinical stage T1 renal cell carcinomas. T3a up staging was noted in 140 patients (11%) and recurrent disease was observed in 44 (31.4%) during a median followup of 38 months. Among up staged T3a cases partial nephrectomy was associated with shorter recurrence-free survival compared to radical nephrectomy on univariable analysis (recurrence HR 2.04, 95% CI 1.12-3.68, p = 0.019) and multivariable analysis (recurrence HR 5.39, 95% CI 1.94-14.9, p = 0.001). CONCLUSIONS: In a subgroup of patients clinically staged T1 renal cell carcinoma will be pathologically up staged to T3a. Among these patients those who undergo partial nephrectomy appear to have inferior recurrence-free survival relative to those who undergo radical nephrectomy.

Processing Adipose-Rich Mohs Samples: A Comparative Study of Effectiveness of Pretreatment With Liquid Nitrogen Versus Flash Freezing Spray.

Processing of adipose-rich Mohs micrographic surgery (MMS) specimens poses challenges that may preclude complete margin evaluation. In this setting, the value of additional freezing methods using various cooling agents has not been previously investigated. The aim of this study is to compare the frozen section quality of high-adipose Mohs specimens processed without additional cooling treatments versus those pretreated with 1,1,1,2-tetrafluoroethane (TFE) or liquid nitrogen (LN2). A set of 3 sections were each taken from 24 adipose-rich Mohs micrographic surgery specimens. A section from each set was subjected to either no additional cooling treatment (control), two 10-second pulse sprays of 1,1,1,2-tetrafluoroethane, or three 2-second pulse sprays of LN2. After staining, 2 blinded raters evaluated slide quality based on the presence or absence of the following features: margin completeness, nuclear clearing, epidermal or adipose folding, holes, or venetian blind-like artifacts. Pretreatment of the sample with LN2 produced a significantly (P < 0.001) greater number of high-quality slides (19/24) compared to pretreatment with 1,1,1,2-tetrafluoroethane (1/24) and no additional treatment (0/24). The adjunctive use of LN2 spray before tissue embedding circumvents the challenges of processing "thick" (high-adipose) specimens and facilitates the production of high-quality frozen section slides during Mohs micrographic surgery.

Functional Implications of Renal Tumor Enucleation Relative to Standard Partial Nephrectomy.

OBJECTIVE: To compare the surgical precision for optimizing nephron-mass preservation of tumor enucleation (TE) vs standard partial nephrectomy (SPN), with primary focus on functional outcomes. TE is presumed to optimize preservation of parenchymal mass and function but this has not yet been rigorously studied and quantified. MATERIALS AND METHODS: Robotic partial nephrectomy patients who had appropriate pre- and postoperative studies for analysis of parenchymal mass preservation specific to the operated kidney were included. Computed tomography or magnetic resonance imaging and estimated glomerular filtration rate were required to be <2 months prior and 4-12 months after surgery. Parenchymal mass preservation and surgical precision were estimated for each technique, with precision defined as actual postoperative parenchymal volume or predicted postoperative parenchymal volume, presuming loss of a 5 mm rim of parenchyma associated with tumor excision and reconstruction. RESULTS: Analysis included 57 TE and 53 SPN. Median age, body mass index, and tumor size were comparable. Percent parenchymal mass preserved in the operated kidney with TE was 96% (interquartile range [IQR] = 90-100) vs 89% (IQR = 83-96) for SPN (P = .003). Precision of excision or reconstruction was 101% (IQR = 96-105) for TE vs 94% (IQR = 88-100) for SPN (P < .001). On multivariable analysis, only TE correlated with improved surgical precision (coefficient = 6.7, 95% confidence interval = 1.6-11.8, P = .01). Although preservation of global renal function also favored TE, the differences were marginal (96% vs 93%), and statistical significance was not observed (P = .2). CONCLUSION: Our analysis, which specifically focuses on the functional implications of TE, demonstrates that TE maximally spares normal parenchyma compared to SPN. Thus far, functional differences remain marginal and not statistically significant. Clinical significance of these findings in various clinical settings will require further investigation.