Low Fuhrman Grade Research Articles

Comparison of survival between unilocular cystic and purely solid renal cell carcinoma

To evaluate clinicopathological features and survival outcomes of unilocular cystic renal cell carcinoma (ucRCC) compared with purely solid renal cell carcinoma (sRCC), and to evaluate the oncologic aggressiveness of ucRCC. The relevant data of 957 patients with sporadic unilateral renal cell carcinoma (RCC) underwent surgical treatment in 2 institutions from Jan 2014 to Oct 2018 were obtained. We excluded multilocular cystic renal neoplasm of low malignant potential (MCRNLMP), RCC with multilocular cysts and necrotic RCC. 74 ucRCCs were identified by pathology reports. We performed propensity score matching (PSM) and eventually selected 144 sRCCs. The clinicopathological features and survival outcomes were compared properly. After PSM, age, BMI, Charlson Comorbidity Index, and postoperative Chronic Kidney Disease grade were not significantly different. Both overall survival and progression-free survival of ucRCC were significantly better than sRCC by the log-rank test. Twenty-five cases of sRCCs were in the pT3 or pT4 stage, while no pT3 or pT4 tumors were found in ucRCCs. Fuhrman grade and lymphatic metastasis were found to be significant prognostic factors for the overall survival of ucRCC. Unilocular cystic RCC has a lower Fuhrman grade and pathological stage and a better prognosis compared with solid RCC. Patients with ucRCC still probably have lymphatic metastasis at surgery and may have postoperative metastasis, which is different from MCRNLMP. We recommend that the diagnosis of ucRCC should be reflected in pathology report. Different subtype of cystic RCC should be taken into consideration in counseling and management.

Multicenter Study of Controlling Nutritional Status (CONUT) Score as a Prognostic Factor in Patients With HIV-Related Renal Cell Carcinoma.

ObjectiveIn recent years, the controlled nutritional status (CONUT) score has been widely recognized as a new indicator for assessing survival in patients with urological neoplasms, including renal, ureteral, and bladder cancer. However, the CONUT score has not been analyzed in patients with HIV-related urological neoplasms. Therefore, we aimed to evaluate the prognostic significance of the CONUT score in patients with HIV-related renal cell carcinoma (RCC).MethodsA total of 106 patients with HIV-related RCC were recruited from four hospitals between 2012 and 2021, and all included patients received radical nephrectomy or partial nephrectomy. The CONUT score was calculated by serum albumin, total lymphocyte counts, and total cholesterol concentrations. Patients with RCC were divided into two groups according to the optimal cutoff value of the CONUT score. Survival analysis of different CONUT groups was performed by the Kaplan–Meier method and a log rank test. A Cox proportional risk model was used to test for correlations between clinical variables and cancer-specific survival (CSS), overall survival (OS), and disease-free survival (DFS). Clinical variables included age, sex, hypertension, diabetes, tumor grade, Fuhrman grade, histology, surgery, and CD4+ T lymphocyte count.ResultThe median age was 51 years, with 93 males and 13 females. At a median follow-up of 41 months, 25 patients (23.6%) had died or had tumor recurrence and metastasis. The optimal cutoff value for the CONUT score was 3, and a lower CONUT score was associated with the Fuhrman grade (P=0.024). Patients with lower CONUT scores had better CSS (HR 0.197, 95% CI 0.077-0.502, P=0.001), OS (HR 0.177, 95% CI 0.070-0.446, P<0.001) and DFS (HR 0.176, 95% CI 0.070-0.444, P<0.001). Multivariate Cox regression analysis indicated that a low CONUT score was an independent predictor of CSS, OS and DFS (CSS: HR=0.225, 95% CI 0.067-0.749, P=0.015; OS: HR=0.201, 95% CI 0.061-0.661, P=0.008; DFS: HR=0.227, 95% CI 0.078-0.664, P=0.007). In addition, a low Fuhrman grade was an independent predictor of CSS (HR 0.192, 95% CI 0.045-0.810, P=0.025), OS (HR 0.203, 95% CI 0.049-0.842, P=0.028), and DFS (HR 0.180, 95% CI 0.048-0.669, P=0.010), while other factors, such as age, sex, hypertension, diabetes, tumor grade, histology, surgery, and CD4+ T lymphocyte count, were not associated with survival outcome.ConclusionThe CONUT score, an easily measurable immune-nutritional biomarker, may provide useful prognostic information in HIV-related RCC.

Long-Term Functional and Oncologic Outcomes of Robot-Assisted Partial Nephrectomy for Cystic Renal Tumors: A Single-Center Retrospective Study.

Objectives: To evaluate the outcomes of robot-assisted partial nephrectomy (RAPN) in cystic renal tumors. Materials and Methods: We retrospectively analyzed patients who underwent RAPN for either cystic (n = 46) or solid (n = 271) renal tumors at Fujita Health University between 2010 and 2019. Cystic renal tumors were diagnosed using cross-sectional imaging. Perioperative, oncologic, and functional outcomes were assessed. Results: The median follow-up periods were 38, 41, and 37 months in the total, cystic, and solid groups, respectively. Most patient characteristics were similar among both groups, while the median age of the cystic group was significantly lower than that of the solid group (p = 0.02). Most perioperative variables and complications were comparable between the two groups. There was no significant difference between the groups in perioperative renal function. The estimated glomerular filtration rate preservation rates were 93.1% and 89.2% in the cystic and solid groups, respectively (p = 0.17). The cystic group showed a higher benign histology rate (19.6% vs 7%) and lower Fuhrman grade than the solid group (24.3% vs 15.1% in grade 1, and 73% vs 81.3% in grade 2), although there was no statistically significant difference between the two groups. In the solid group, 10 patients (3.7%) experienced recurrence, and 2 patients (0.7%) died of renal-cell carcinoma, while none of the patients with cystic tumors experienced recurrence. There was no statistically significant difference between the cystic and solid tumors with respect to 5-year recurrence-free survival (p = 0.18), cancer-specific survival (p = 0.55), and overall survival (p = 0.35). Conclusions: RAPN for cystic renal tumors appears to be safe and feasible with perioperative, long-term functional and oncologic outcomes comparable with those in solid tumors. RAPN can be a safe and effective surgical option for cystic renal tumors.

Using texture analysis as a predictive factor of subtype, grade and stage of renal cell carcinoma.

The aim of this study was to evaluate the correlation between the tissue texture analysis and the histological subtypes, grade and stage of the disease in patients with renal cell carcinoma (RCC). Seventy-seven patients who underwent computed tomography due to renal mass and diagnosed with RCC as a result of pathological examination were retrospectively analyzed. In these analyses, the demographic characteristics, pathological and radiological findings of the patients were evaluated. The masses were introduced to the Radiomics extension of the software and the first- and second-order texture analysis parameters were obtained. The correlation of these parameters with histological subtype, Fuhrman grade and TNM stage was investigated. In the comparison of the Radiomics values by stages, "minimum", "Long Run Low Gray-level Emphasis" values were higher in the stage 1-2 group, while "Energy", "Total energy", "Range", "Joint Average", "Sum Average", "Gray-Level Non-Uniformity", "Short-Run High Gray-level Emphasis ", "Run Length Non-Uniformity "and "High Gray-Level Run Emphasis "values were higher in the stage 3-4 group. Of these parameters, only "Gray-Level Non-Uniformity" and "Run Length Non-Uniformity'' values were significantly lower in tumors with low Fuhrman grade (1-2) and low TNM stage (1-2). There was no statistically significant correlation between the parameters found to be significant in histological subtype differentiation and Fuhrman grade and TNM stage. This study demonstrates that "Gray-Level Non-Uniformity" and "Run Length Non-Uniformity "parameters in the texture analysis method can be used to evaluate the prognosis in patients with RCC.

Expression of HIF-2a in clear-cell renal cell carcinoma independently predicts overall survival.

The purpose of this study is to evaluate the expression and the prognostic role of main factors, involved in the hypoxia pathway, in patients with clear-cell renal cell carcinoma (ccRCC). Immunohistochemical expression of Hypoxia inducible factors (HIF) HIF-1a, HIF-2a, prolyl hydroxylases PHD1, PHD2, PHD3, and factor inhibiting HIF (FIH) was assessed on a tissue microarray, containing tumour and corresponding normal kidney tissue from 66 patients underwent surgery for ccRCC. Expression levels were evaluated in relation to T stage, Fuhrman grade, cancer-specific, and overall survival (OS). Cytoplasmatic expression of HIF-2a was positively correlated with expression of HIF-1a (p = 0.011). HIF-1a expression was also positively correlated with PHD3 and FIH (p = 0.020 and p = 0.039). Expression of HIF-1a was associated with lower Fuhrman grade (p = 0.008), while HIF-2a overexpression with unfavourable grade (p = 0.026). PHD3 was significant downregulated (84.8%). Age, LDH, presence of necrosis, Fuhrman grade, T stage, and HIF-2a cytoplasmatic expression were significant associated with OS of patients in univariable analysis. In multivariable analysis, HIF-2a expression (p = 0.006) and T stage (p = 0.001) remained as the only independent predictors for overall survival. These results indicate that HIF-2a overexpression not only is inversely correlated with Fuhrman grade in ccRCC, but also represents a strong independent prognostic factor for a poor overall survival.

The prognostic effect of immunoscore in patients with clear cell renal cell carcinoma: preliminary results.

This study aimed to evaluate the density of CD8+ and CD3+ tumor-infiltrating lymphocytes (TILs) and determine whether the immunoscore has any prognostic effect on the oncological outcomes in patients with clear cell renal cell carcinoma (RCC). A total of 129 patients diagnosed with clear cell RCC following radical or partial nephrectomy between 2009 and 2014 were retrospectively analyzed. Both tumor core (CT) and the invasive margin of nephrectomy specimens were assessed. The specimens were immunostained for anti-CD8+ and anti-CD3+ TILs. The patients were divided into three groups (favorable, intermediate, and poor risk) according to immunoscore levels. In the multivariate analysis, a favorable immunoscore (I3-4) was associated with prolonged disease-free survival (DFS), progression-free survival (PFS), and overall survival (OS) (HR 2.652, 2.848, and 2.933, respectively; all p < 0.001). The lower Fuhrman grade and pathological tumor-node-metastasis (TNM) stage had better DFS, PFS, and OS, whereas prolonged PFS was associated with a higher density of CD8+ CT (HR 1.602, 95% CI 0.934-3.470; p = 0.014). The shorter DFS, PFS, and OS were observed in the group with poor immunoscore (I0-1) at the early TNM stage of RCC (p < 0.001). In the metastatic subgroup analysis, the immunoscore showed better estimation than the International Metastatic RCC Database Consortium model and the Memorial Sloan-Kettering Cancer Center risk model for progression and OS (p < 0.001). The additional contributions of immunoscore to TNM stage, Fuhrman grade, and the WHO/ISUP 2016 grade for estimating oncological outcomes were found in ROC analysis. According to our preliminary results, immunoscore can be a promising prediction tool in clear cell RCC for postoperative oncological outcomes following nephrectomy.

03:00 PM Abstract No. 286 Deep learning based on MR imaging for differentiation of low grade and high grade renal cell carcinoma

Pre-treatment determination of renal cell carcinoma (RCC) aggressiveness may help guide clinical decision making, informing who may benefit from surveillance versus intervention with ablation or resection. Fuhrman grade has been shown to be a predictor of survival in RCC patients. We aimed to differentiate low grade (Fuhrman I–II) from high grade (Fuhrman III–IV) RCC using routine MR imaging by training a residual convolutional neural network (ResNet). Preoperative MR images (T2-weighted (T2) and T1-post contrast (T1C) sequences) of 300 patients with RCC lesions in a multicenter cohort were acquired. The overall cohort was divided into training, validation, and testing set (70:20:10 split). A ResNet model combining MR images and three clinical variables (age, gender, and tumor size) was built using bagged probabilities and bagged regression to predict tumor grade. In the bagged probabilities version, the T1C, T2, and clinical variables models predict probability of high grade while in the bagged regression version, these models predict Fuhrman grade (float from 0 to 4). In both cases, the output (either probability or float) are bagged into the final classifier. Final model performance was compared with two human experts. Among the 300 patients included, 107 had high Fuhrman grade tumor and 193 had low Fuhrman grade tumor. Our bagged probabilities model achieved a test accuracy of 80.6% (AUC=0.86) with 72.7% sensitivity and 85.0% specificity. Our bagged regression model achieved a test accuracy of 81.8% (AUC=0.75) with 68.4% sensitivity and 88.9% specificity. In comparison, expert 1 achieved accuracy of 60.1% (AUC= 0.63) with 69.8% sensitivity and 55.7% specificity, and expert 2 achieved accuracy of 55.7% (AUC= 0.57) with 62.3% sensitivity and 52.1% specificity. Deep learning can non-invasively predict Fuhrman tumor grade of RCC using conventional MR imaging in a multi-institutional dataset with high accuracy. This non-invasive technique could help clinicians optimize patient management.

CD105 as a tool for assessing microvessel density in renal cell carcinoma.

Angiogenesis plays an essential role in both tumor growth and metastasis. CD105 expression was correlated with prognosis in many tumors, but its value in renal cell carcinoma (RCC) is still questionable. The aim of this study was to evaluate microvessel density (MVD) by using CD105 marker, in 95 cases of renal cell carcinoma. CD105 showed positivity in 93 cases. The mean MVD value was significantly higher in clear cell carcinoma compared to papillary and chromophobe subtypes (P = 0.000). We noticed a significant correlation between MVD and ISUP grade (P = 0.007). The highest MVD value was observed in tumors with ISUP grade 1 and 2, while the lowest MVD value was noted in ISUP grade 3 tumors. A high vessel density was identified in tumors with a low Fuhrman grade, compared to those with a high grade (P = 0.010). MVD value was lower in tumors with a larger diameter, compared to small ones (P = 0.026). In conclusion, CD105 expression (MVD) is inversely related to tumor aggressiveness in clear cell RCC and can be used as a favorable prognosis marker. The vascularity differences between histological subtypes of RCCs could be useful for a better selection of patients that may benefit from anti-angiogenic therapies.

Preoperative apolipoprotein B/A1 ratio is an independent prognostic factor in metastatic renal cell carcinoma

ObjectivesWe aimed to explore the prognostic value of preoperative apolipoprotein B/apolipoprotein A1 (Apo B/A1) ratio in metastatic renal cell carcinoma (mRCC). Materials and methodsBetween January 2006 and December 2016, patients with mRCC who underwent cytoreductive nephrectomy at the Chinese PLA General Hospital were enrolled. The clinical-pathological parameters were collected retrospectively, and the preoperative Apo B/A1 ratios of two different subgroups were compared. The cut-off value was determined with the receiver operating characteristic (ROC) curve. The value of preoperative Apo B/A1 ratio on oncological outcome was determined through Kaplan–Meier survival analysis and Cox regression analysis. ResultsA total of 287 mRCC patients were enrolled in this study. The median postoperative follow-up time was 27.8 months (IQR, 12.5–58.6 months). The Apo B/A1 ratio was higher in the high Fuhrman grade (G3 and G4) group than that in the low Fuhrman grade (G1 and G2) group (P = 0.010). The area under the curve values of the ROC curves were 0.613 for progression-free survival (PFS) (P = 0.005) and 0.607 for overall survival (OS) (P = 0.004). The optimal cut-off values of Apo B/A1 ratio were 0.977 for PFS and 0.847 for OS. A high preoperative Apo B/A1 ratio (PFS ≥ 0.977; OS ≥ 0.847) was significantly associated with poor PFS (P < 0.0001) and OS (P = 0.0005). Cox regression analyses showed that the Apo B/A1 ratio is an independent prognostic factor for PFS (hazard ratio [HR] = 3.131; 95% confidence interval [CI] = 2.249–4.360; P < 0.001) and OS (HR = 2.173; 95% CI = 1.533–3.080; P < 0.001). ConclusionPreoperative Apo B/A1 ratio is an independent prognostic factor for PFS and OS in patients with mRCC. Preoperative Apo B/A1 ratio can be useful in improving current prognostic evaluation and treatment decision for patients with mRCC.

Carcinome rénal à cellules chromophobes : à propos de 16 cas et une revue de la littérature

ObjectiveTo determine the histo-clinical, pathological, therapeutic and prognostic characteristics of renal chromophobe carcinomas. Subjects and methodsThis is a retrospective study including 16 cases of chromophobe carcinoma among 86 renal cancers diagnosed in the Urology Department B of Rabat University Hospital between January 2011 and August 2017. ResultsThere were 12 women and 4 men. The average age of discovery was 57.5 years. They were distributed in 62.5% predominantly eosinophilic, 37.5% of mixed tumors. The nuclei are irregular and incisured. Tumor T1 (31.5%) and T2 (56.25%) were the most common. The majority of patients had a Fuhrman grade, 43.8% grade 2 and 31.2% grade 3. Only one patient had a local recurrence. The overall 5-year survival rate was 92%. A death related to the disease has been reported. Nephrectomy is the gold standard for 100% of patients. The average overall survival rate is 34.4 months. ConclusionChromophobic kidney cancer is a particular anatomo-clinical entity, characterized by a favorable prognosis due to a low Fuhrman grade and its limitation to the kidney.

The true malignancy risk of Bosniak III cystic renal lesions: Active surveillance or surgical resection?

We sought to evaluate the pathological results of renal masses in comparison with Bosniak III renal cystic lesions to determine the actual malignancy risk. A retrospective review of Bosniak III renal lesions identified by computed tomography (CT) or magnetic resonance imaging (MRI) were collected from our patients between August 1, 2013 and December 31, 2015 who underwent surgical excision. TNM stage, histology, Fuhrman grade, and maximum lesion size data was collected. Lesion size relationship with prevalence of malignancy was completed by two-tailed t-test, using the homogeneity hypothesis between malignant and benign groups. Fifteen of 25 (60%) of Bosniak III lesions were determined to be malignant. All malignant lesions were classified as either Fuhrman grade 1 or 2 with no evidence of progression to Bosniak IV. Average size of malignant lesions was smaller than those of benign pathology (3.52±1.99 cm vs. 5.66±2.53 cm; p=0.041). Smaller lesions (size <4 cm) were more likely to be malignant than lesions of a larger size (p=0.047). The malignancy risk of Bosniak III renal lesions was 60% in our study. All Bosniak III lesions were of low Fuhrman grade with no evidence of progression. No patient in this study developed metastatic disease within the three-year followup period. Smaller (<4 cm) Bosniak III cysts were more likely to be malignant and lesion size should be taken into consideration when considering management of complex cysts. Active surveillance may be a reasonable option for Bosniak III cystic lesions, regardless of overall size, based upon their universal low grade and no patient developing metastatic disease.

Valproic acid inhibits epithelial‑mesenchymal transition in renal cell carcinoma by decreasing SMAD4 expression.

Renal cell carcinoma (RCC) is the most common malignancy in urogenital neoplasms worldwide. According to previous studies, valproic acid (VPA), an anticonvulsant drug, can suppress tumor metastasis and decrease the expression level of Mothers against decapentaplegic homolog 4 (SMAD4) and therefore may inhibit epithelial‑mesenchymal transition (EMT), which is responsible for cancer metastasis. However, the association between VPA, EMT and SMAD4 in RCC metastasis remains obscure. In the present study, it was demonstrated that in the RCC cell lines 786‑O and Caki‑1 treated with VPA, the neural (N)‑cadherin, vimentin and SMAD4 protein and mRNA levels were decreased, accompanied with an increase in expression of epithelial (E)‑cadherin. Silencing SMAD4 expression decreased the expression of EMT markers, including N‑cadherin and simultaneously upregulated E‑cadherin in RCC cell lines. SMAD4 overexpression counteracted the VPA‑mediated EMT‑inhibitory effect (P<0.05). The present study demonstrates that VPA inhibited EMT in RCC cells via altering SMAD4 expression. In addition, immunohistochemical staining demonstrated that transforming growth factor‑β (TGF‑β) and low expression of SMAD4 was associated with a lower Fuhrman grade and low expression of transcription intermediary factor 1‑γ was associated with a higher tumor Fuhrman grade (P<0.05), Therefore, based on the regulatory effect of SMAD4 on EMT‑associated transcription factors, SMAD4 which can form a SMAD3/SMAD4 complex induced by TGF‑β, could be a potential anticancer drug target inhibiting tumor invasion and metastasis in RCC.

Multilocular cystic renal cell carcinoma: pathological t staging makes no difference to favorable outcomes and should be reclassified. Bhatt JR, Jewett MA, Richard PO, Kawaguchi S, Timilshina N, Evans A, Alibhai S, Finelli A.J Urol. November 2016;196(5):1350–1355.

ObjectiveWe evaluated survival outcomes of cystic/multilocular cystic renal cell carcinomas in a long-term population-based study based on size and pathological tumor stage. Materials and methodsWe, retrospectively, reviewed a provincial cancer registry of all histologically proven cases of multilocular cystic renal cancers treated surgically between 1995 and 2008. All cases of cystic necrosis were excluded from study. Primary end points were overall- and cancer-specific survival estimated using Kaplan-Meier curves. Cox proportional hazards models of univariable and multivariable analyses were used to assess for factors associated with survival. ResultsOf 172 cases of cystic renal cancers 168 with complete data were analyzed, of which 98% were multilocular cystic. Median patient age at treatment was 55 years and 58% of the patients were male. More than 40% of cases were pT1b or greater, 15% were pT2 or greater and most cases were low Fuhrman grade (1–2). At a median follow-up of 9.75-years overall- and cancer-specific survival was 82.1% and 100%, respectively. No difference was noted in higher pathological T stage, size, or grade. Limitations inherent in population-based studies include under ascertainment of cause of death, lack of data on histologically benign cysts that are treated surgically and a lack of central pathology review. ConclusionsMultilocular cystic renal cell carcinoma has an excellent prognosis, which remains unchanged regardless of tumor size or pathological T stage. This suggests a strong case for nephron and adrenal sparing surgery when indicated, and nonsurgical management when feasible. As postoperative follow-up protocols are dictated by staging, we propose that for this entity pathological T staging should be abandoned or reassigned as pT1c to guide clinicians.

The predictive and prognostic values of serum amino acid levels for clear cell renal cell carcinoma

ObjectivesTo investigate the predictive and prognostic values of the logistic regression model based on the serum amino acid levels. Materials and methodsThe study enrolled 42 patients with clear cell renal cell carcinoma (ccRCC) and 66 matched healthy people admitted to PLA General Hospital from April 2015 to June 2015. Serum samples from the 2 groups were analyzed by isobaric tags for relative and absolute quantitation-liquid chromatography-tandem mass spectrometry (iTRAQ-LC-MS/MS) method. Variables of the 2 groups were compared by Student’s t-test or chi-square test. The prediction model was constructed by logistic regression analysis. Oncological outcomes were evaluated by Kaplan-Meier survival analysis and Cox regression analysis. ResultsPathological diagnosis confirmed that all patients had ccRCC. No significant differences were found in the distribution of age, sex, or body mass index between patients with ccRCC and matched healthy people. A total of 32 amino acids were quantitatively analyzed, and serum levels of 23 amino acids were significantly different between the 2 groups. A predictive logistic regression model containing histidine, glutamine, 1-methyl histidine, and norvaline was constructed. Receiver operating characteristic (ROC) curves for all patients with ccRCC and controls, patients with T1 ccRCC and controls, patients with Fuhrman grade 1 to 2 ccRCC and controls, patients with T2 ccRCC and controls, and patients with Fuhrman grade 3 ccRCC and controls were drawn based on the model. The area under the curve values of the 5 receiver operating characteristic curves were 0.878, 0.885, 0.890, 0.830, and 0.788, respectively. Patients with higher model scores (>2) had significantly poorer progression-free survival (PFS) than patients with lower model scores (≤2). Multivariable Cox regression analysis showed that logistic regression model score was an independent predictor of PFS. ConclusionSerum amino acid levels are a potential predictive biomarker for distinguishing patients with ccRCC, especially early T-stage and low Fuhrman grade patients, from healthy people. Serum amino acid levels can also be used in the prognostic evaluation of patients with ccRCC.

Morphological Characterization of Papillary Renal Cell Carcinoma Type 1, the Efficiency of Its Surgical Treatment

Aim: Papillary renal cell carcinoma type 1 (pRCC1) represents the second most common type of malignant renal epithelial tumour. The origin of its characteristic appearance, its growth mechanism, and the long-term efficiency of its surgical treatment remain uncertain. Our aim was to determine typical characteristics of surgically treated pRCC1. Methods: pRCC1 was verified in 83 of 1,629 (5.1%) kidney tumours surgically treated in the period of January 2007-January 2016. The clinical and radiological characteristics, type of surgery, histopathology results and follow up data were recorded. Spearman correlation, Kruskal-Wallis analysis of variance, Fisher's exact, and chi-square test were used to analyse appropriate variables. The overall survival rate was evaluated using the Gehan-Wilcoxon test and the Cox proportional hazards model. Results: The mean tumour size was 52.0 mm (15-180); 98.8% of the tumours showed a spherical shape and in 82.1%, exophytic growth was observed. Partial nephrectomy was performed in 80.7%. A majority (81.9%) were classified as pT1. Tumours, 89.2% of them, belonged to Fuhrman grade 1 or 2. The mean follow-up was 46.8 months. The overall survival was associated with pT category (p ≤ 0.0001). Conclusions: Typical signs of pRCC1 are a spherical shape, exophytic growth and low Fuhrman's grade. More than three-fourths of pRCC1 could be treated by the nephron-sparing surgery.

Robot-assisted partial nephrectomy confers excellent long-term outcomes for the treatment of complex cystic renal tumors: Median follow up of 58 months.

To analyze long-term outcomes of robot-assisted partial nephrectomy for treatment of complex cystic renal tumors. We retrospectively analyzed the data of patients who underwent robot-assisted partial nephrectomy for cystic (n = 32) and solid (n = 263) renal masses at Severance Hospital, Seoul, Korea. The primary outcome was assessment of perioperative safety for cystic tumor. Secondary outcomes were evaluation of long-term oncological and functional results. Patients' clinical and demographic characteristics were similar among both groups. The median follow up of cystic and solid masses were 58 and 46 months, respectively. Cystic masses were more likely to have low Fuhrman grade 1 and 2 (P = 0.03), and shorter operative time (P = 0.04) compared with solid masses. There was no statistically significant difference regarding warm ischemia time, estimated blood loss, trifecta achievement, length of hospital stay, complication rates and renal function preservation (P > 0.05) between groups. In the solid group, 12 patients (4.1%) recurred, and six patients (2%) died from metastatic renal cell carcinoma, whereas the patients in the cystic group did not have any local or distance recurrence, and the survival rates were 100%. The 5-year cancer-free survival (P = 0.77), cancer-specific survival (P = 0.65) and overall survival (P = 0.83) rates were similar between the groups. Robot-assisted partial nephrectomy appears to be safe and feasible treatment for complex cystic renal masses. It confers excellent long-term oncological outcomes. Robot-assisted partial nephrectomy should be the treatment of choice for complex cysts whenever feasible.

Multilocular Cystic Renal Cell Carcinoma: Pathological T Staging Makes No Difference to Favorable Outcomes and Should be Reclassified

We evaluated survival outcomes of cystic/multilocular cystic renal cell carcinomas in a long-term population based study based on size and pathological tumor stage. We retrospectively reviewed a provincial cancer registry of all histologically proven cases of multilocular cystic renal cancers treated surgically between 1995 and 2008. All cases of cystic necrosis were excluded from study. Primary end points were overall and cancer specific survival estimated using Kaplan-Meier curves. Cox proportional hazards models of univariable and multivariable analyses were used to assess for factors associated with survival. Of 172 cases of cystic renal cancers 168 with complete data were analyzed, of which 98% were multilocular cystic. Median patient age at treatment was 55years and 58% of the patients were male. More than 40% of cases were pT1b or greater, 15% were pT2 or greater and most cases were low Fuhrman grade (1-2). At a median followup of 9.75 years overall and cancer specific survival was 82.1% and 100%, respectively. No difference was noted in higher pathological T stage, size or grade. Limitations inherent in population based studies include under ascertainment of cause of death, lack of data on histologically benign cysts that are treated surgically and a lack of central pathology review. Multilocular cystic renal cell carcinoma has an excellent prognosis, which remains unchanged regardless of tumor size or pathological T stage. This suggests a strong case for nephron and adrenal sparing surgery when indicated, and nonsurgical management when feasible. Since postoperative followup protocols are dictated by staging, we propose that for this entity pathological T staging should be abandoned or reassigned as pT1c to guide clinicians.

MP85-10 IDENTIFICATION OF WDR20 AS A NEW TUMOR SUPPRESSOR GENE PREFERENTIALLY ALTERED IN HIGH-GRADE CLEAR CELL RENAL CELL CARCINOMA.

INTRODUCTION AND OBJECTIVES: There are more than 200,000 cases of renal cell carcinoma (RCC) each year in the world, accounting for approximately 2% of all cancers. RCC clear cell type (ccRCC) is the most common subtype of RCC and accounts for 75 to 80% of the cases with highest rates of local invasion, development of metastasis and mortality. New target therapy is based on antiangiogenic antibodies and molecules, changing the course of the disease, but the results so far are disappointing. Our aim is to study miRNAs and their target genes related to angiogenesis in ccRCC trying to bring some new knowledge to the molecular pathways related to the disease METHODS: The expression levels of miRNAs miR-99a, 99b, 100; 199a; 106a; 106b; 29a; 29b; 29c; 126; 200a, 200b and their respective target genes: mTOR, HIF1-a, VHL, PDGF, VEGF, VEGFR1 and VEGFR2 were evaluated using qRT-PCR.in snap-frozen tumor tissue samples from 56 patients diagnosed with ccRCC and 5 samples of benign renal tissue as control. The results were related to tumor size, Fuhrman nuclear grade and microvascular invasion, considering the risk criteria proposed by Dall’Oglio et al. (2007). RESULTS: We found an underexpression of the most genes except the VEGFA and PDGF, while the analysis of miRNAs showed underexpression only the miR 199a, 100 and 126. We compared the expression of genes with their possible regulatory miRNAs, and we found that mTOR was underexpressed while miR99a was overexpressed in most samples. This relationship also occurs between VEGFA and miR126 and between miRNAs 106a, 106b, and their target gene VHL. Considering the risk groups the overexpression of miR200b was associated with high-risk patients (p 1⁄4 0.01) and the overexpression of miR126 was associated with lower Fuhrman grade (I-II) (p 1⁄4 0.03). CONCLUSIONS: Our results show that in ccRCC there is an unbalance in the expression of genes and miRNAs related to angiogenesis and cell proliferation and survival. Furthermore with our findings we can speculate the role of miR200b and miR126 in the prognostic of ccRCC. We believe that the relationship between miRNAs and their respective genes should be more profoundly searched as markers and possible therapeutic agents in this neoplasia.

MP85-11 GENETIC DELETION OF SAV1 ENHANCES PROLIFERATION AND NUCLEAR IRREGULARITY IN RENAL TUBULAR EPITHELIAL CELLS

INTRODUCTION AND OBJECTIVES: There are more than 200,000 cases of renal cell carcinoma (RCC) each year in the world, accounting for approximately 2% of all cancers. RCC clear cell type (ccRCC) is the most common subtype of RCC and accounts for 75 to 80% of the cases with highest rates of local invasion, development of metastasis and mortality. New target therapy is based on antiangiogenic antibodies and molecules, changing the course of the disease, but the results so far are disappointing. Our aim is to study miRNAs and their target genes related to angiogenesis in ccRCC trying to bring some new knowledge to the molecular pathways related to the disease METHODS: The expression levels of miRNAs miR-99a, 99b, 100; 199a; 106a; 106b; 29a; 29b; 29c; 126; 200a, 200b and their respective target genes: mTOR, HIF1-a, VHL, PDGF, VEGF, VEGFR1 and VEGFR2 were evaluated using qRT-PCR.in snap-frozen tumor tissue samples from 56 patients diagnosed with ccRCC and 5 samples of benign renal tissue as control. The results were related to tumor size, Fuhrman nuclear grade and microvascular invasion, considering the risk criteria proposed by Dall’Oglio et al. (2007). RESULTS: We found an underexpression of the most genes except the VEGFA and PDGF, while the analysis of miRNAs showed underexpression only the miR 199a, 100 and 126. We compared the expression of genes with their possible regulatory miRNAs, and we found that mTOR was underexpressed while miR99a was overexpressed in most samples. This relationship also occurs between VEGFA and miR126 and between miRNAs 106a, 106b, and their target gene VHL. Considering the risk groups the overexpression of miR200b was associated with high-risk patients (p 1⁄4 0.01) and the overexpression of miR126 was associated with lower Fuhrman grade (I-II) (p 1⁄4 0.03). CONCLUSIONS: Our results show that in ccRCC there is an unbalance in the expression of genes and miRNAs related to angiogenesis and cell proliferation and survival. Furthermore with our findings we can speculate the role of miR200b and miR126 in the prognostic of ccRCC. We believe that the relationship between miRNAs and their respective genes should be more profoundly searched as markers and possible therapeutic agents in this neoplasia.

Pathological features of clinical T1b renal cell carcinoma

Objective To investigate the pathological characters of clinical T1b (4<diameter≤7 cm) renal cell carcinoma and provide reference basis for the nephron sparing surgery (NSS). Methods From January 2002 to December 2014, the pathological features of clinical T1b renal cell carcinoma were studied in 710 cases, including 505 male cases and 205 female cases. The mean age was 58 years old, ranged from 26 to 88 years old. The location of tumor included 377 in left side and 383 in right side. In the recorded 372 cases, the accurate site of tumor included 137 in upper portion, 96 in middle portion and 139 in lower portion. The initial symptom included hematuria in 103 cases, back pain in 62 cases, hematuria accompanied with back pain in 34 cases and asymptom in 511 cases. The diameter of tumor ranged from 4.0 to 7.0 cm, mean 5.4 cm. We analyzed pathological features, Fuhrman grades, histologic subtype, tumor metastasis, perirenal fat invasion and vein tumor thrombosis in all patients. Results The proportions of the clear cell, papillary, chromophobe, unclassified and mixed cell histologic subtype were 75.8% (538/710), 5.1% (36/710), 4.6% (33/710), 1.1% (8/710) and 13.4% (95/710), respectively. The proportions of hemorrhage, necrosis, cystic degeneration and fibrosis were 51.0% (362/710), 30.1% (214/710), 35.4% (251/710) and 7.8% (55/710), respectively. The rates of perirenal fat invasion and vein tumor thrombosis were 4.1% (29/710) and 3.1% (22/710). Among the 710 clinical T1b renal cell carcinoma, 144 (20.3%) were Fuhrman gradeⅠ, 513 (72.3%) were grade Ⅱ, 43 (6.1%) were grade Ⅲ, 10 (1.4%) were grade Ⅳ. In 657 cases with low Fuhrman grade(Ⅰ/Ⅱ), 17 cases were noticed perirenal fat invasion.In 53 cases with high Fuhrman grade (Ⅲ/Ⅳ), 10 cases were noticed perirenal fat invasion. The analysis showed that high Fuhrman grading was concerned with the perirenal fat invasion. Conclusions Clinical T1b renal cell carcinoma has obvious heterogeneity in its biological behavior. Most of them has characters of high differentiation, low malignant tendency and good biological behavior. Rare carcinoma exhibits the aggressive character or early distant metastasis. During the nephron sparing surgery, perirenal fat should be removed and perform pathological examination. Vein tumor thrombosis should be bolt out and radical nephrectomy is recommended at the same time. Key words: Carcinoma, renal cell; Pathology; Nephron sparing surgery