Identification and Validation of Radiographic Enhancement for Reliable Differentiation of CD117(+) Benign Renal Oncocytoma and Chromophobe Renal Cell Carcinoma.

Purpose: The diagnostic differential for CD117/KIT(+) oncocytic renal tumor biopsies is limited to benign renal oncocytoma versus chromophobe renal cell carcinoma (ChRCC); however, further differentiation is often challenging and requires surgical resection. We investigated clinical variables that might improve preoperative differentiation of CD117(+) renal oncocytoma versus ChRCC to avoid the need for benign tumor resection.Experimental Design: A total of 124 nephrectomy patients from a single institute with 133 renal oncocytoma or ChRCC tumors were studied. Patients from 2003 to 2012 comprised a retrospective cohort to identify clinical/radiographic variables associated with renal oncocytoma versus ChRCC. Prospective validation was performed among consecutive renal oncocytoma/ChRCC tumors resected from 2013 to 2017.Results: Tumor size and younger age were associated with ChRCC, and multifocality with renal oncocytoma; however, the most reliable variable for ChRCC versus renal oncocytoma differentiation was the tumor:cortex peak early-phase enhancement ratio (PEER) using multiphase CT. Among 54 PEER-evaluable tumors in the retrospective cohort [19 CD117(+), 13 CD117(-), 22 CD117-untested], PEER classified each correctly as renal oncocytoma (PEER >0.50) or ChRCC (PEER ≤0.50), except for four misclassified CD117(-) ChRCC variants. Prospective study of PEER confirmed 100% accuracy of renal oncocytoma/ChRCC classification among 22/22 additional CD117(+) tumors. Prospective interobserver reproducibility was excellent for PEER scoring (intraclass correlation coefficient, ICC = 0.97) and perfect for renal oncocytoma/ChRCC assignment (ICC = 1.0).Conclusions: In the largest clinical comparison of renal oncocytoma versus ChRCC to our knowledge, we identified and prospectively validated a reproducible radiographic measure that differentiates CD117(+) renal oncocytoma from ChRCC with potentially 100% accuracy. PEER may allow reliable biopsy-based diagnosis of CD117(+) renal oncocytoma, avoiding the need for diagnostic nephrectomy. Clin Cancer Res; 24(16); 3898-907. ©2018 AACR.

Outcomes of Minimal Invasive vs Open Radical Nephrectomy for the Treatment of Locally Advanced Renal-Cell Carcinoma.

PURPOSE: We compare oncologic outcomes of minimally invasive and open nephrectomy for locally advanced kidney cancer. MATERIALS AND METHODS: A retrospective review of a single-institutional, prospectively maintained database from a National Comprehensive Cancer Network-designated center was conducted. All patients who underwent radical nephrectomy at Roswell Park Cancer Institute with diagnosis of pT3 and pT4 renal-cell carcinoma (RCC) between years 1998 and 2015 were reviewed. Patients who underwent partial nephrectomy and nephroureterectomy were excluded. RESULTS: We identified 172 patients with pT3 or pT4 tumors resected by minimally invasive (laparoscopic and robotic) or open radical nephrectomy. Demographic characteristics were similar between the two groups. Patients in the minimally invasive group had a higher mean body mass index (31.9 vs 28.1, p = 0.002), radiologically smaller tumors (7.7 cm vs 9.1 cm, p = 0.008), lower mean estimated blood loss (277 vs 1429, p < 0.001), lower rate of blood transfusion (4.7% vs 45.5%, p < 0.001), and a shorter mean length of stay (3.5 days vs 5.7 days, p < 0.001) compared with patients who underwent open surgery. At a median follow-up of 32.8 months, there was no significant difference in overall survival (p = 0.8) between the two groups. CONCLUSION: Minimal invasive nephrectomy is a safe approach with similar oncologic outcomes to open nephrectomy for select patients with locally advanced RCC.

Minimally invasive cytoreductive nephrectomy: a multi-institutional experience.

PURPOSE: To analyze the functional and oncologic outcomes of minimally invasive cytoreductive nephrectomy (CN) in three high-volume cancer centers. PATIENTS AND METHODS: Three prospectively maintained, IRB-approved kidney surgery databases were queried from three high-volume cancer centers. All patients who underwent minimally invasive surgery (laparoscopic, hand-assisted laparoscopic, or robotic) partial or radical CN with existing measurable extra-renal metastatic disease between May 2001 and May of 2013 were included in this analysis. RESULTS: We identified 120 patients who underwent minimally invasive CN for metastatic renal cell carcinoma. Most of the surgeries were radical (93.3 %) and performed laparoscopically (96.6 %). Median operative time was 210 min, with a median estimated blood loss of 150 cc, and 11 (9.2 %) patients received blood transfusions. Four (3.3 %) patients were converted to open surgery due to locally advanced disease and/or bleeding. Postoperative complications were seen in 28 (23.3 %) patients, of which 20 (71.4 %) were classified as minor (Clavien-Dindo I-II). The median survival of the entire cohort was 25.7 months, with a 3-year survival rate of 35 %. Multivariate analysis indicated that only hypertension, brain metastasis, and pT stage were independently associated with worse overall survival (HR > 1). CONCLUSIONS: Minimally invasive cytoreductive nephrectomy is feasible and safe in experienced hands with acceptable morbidity and oncological outcomes.

Early identification of asymptomatic brain metastases from renal cell carcinoma.

Current guidelines for metastatic renal cell carcinoma (mRCC) do not recommend routine brain imaging as part of the surveillance protocol unless central nervous system (CNS) symptoms or abnormal laboratory values suggest brain involvement. We hypothesized that strict adherence to these guidelines will delay diagnosis and management of RCC brain metastases. Retrospective review of our IRB-approved kidney cancer database examined a consecutive series of subjects from 1995 to 2012. We identified all mRCC patients with radiographic evidence of renal cell brain metastasis (RCCBM). RCCBM patients were divided into two cohorts: CNS symptoms present at RCCBM diagnosis and those without symptoms present at diagnosis. Fifty-two patients within our database met criteria; CNS symptoms were present at RCCBM diagnosis in 73 % (36) of patients. Median size of RCCBM on presentation was smaller in the asymptomatic verses the symptomatic cohort (0.83 vs. 1.7 cm, p = 0.003). Multivariate analysis demonstrated presence of CNS symptoms and female gender as a survival advantage (p < 0.05) while poor performance status, history of tobacco abuse and coexistence of lung metastasis were poor indicators for survival (p < 0.05). Patients with pulmonary metastases and a history of tobacco abuse are more likely to harbor RCCBM and perhaps in the absence of CNS symptoms these subjects should have routine brain surveillance incorporated into the RCC follow up. Overall, the current urologic guidelines may be missing a subset of metastatic RCC patients who could potentially benefit from early radiation or neurosurgical intervention. This may result in improved overall survival.