Upstaging to pT3a disease in patients undergoing robotic partial nephrectomy for cT1 kidney cancer: Outcomes and predictors from a multi-institutional dataset

Partial nephrectomy after a period of active surveillance: Are perioperative and pathology outcomes worsened compared to immediate surgery?

INTRODUCTION

Active surveillance (AS) is a viable strategy for managing small renal masses (SRMs) in lieu of immediate surgery, but concerns persist regarding its impact on delayed partial nephrectomy (PN) outcomes. We aimed to compare perioperative and pathological outcomes of patients initially on AS for SRMs, later undergoing PN, against those undergoing immediate PN.

MATERIALS AND METHODS

Data were extracted from a prospective institutional database (January 2018-September 2023) for patients with cT1a renal masses. Only malignancies confirmed at final pathology were included. Baseline patient and tumor characteristics and the time from AS enrollment to PN were recorded. Surgical, renal functional, and final pathology outcomes were analyzed, including histology, tumor size, pT stage, upstaging rate, and positive surgical margins. Predictors of upstaging were identified using logistic regression models.

RESULTS

Analysis included 356 patients: 307 immediate PN and 49 deferred PN after a median of 18 months in AS. Groups had comparable baseline characteristics; no significant differences emerged in surgical and postoperative outcomes. Final pathology revealed no significant disparities in tumor size, histology, positive margins, or upstaging, though pT stage distribution differed (2.4 % versus 4.3 % for pT3a, immediate versus deferred, p = 0.04). Univariable analysis identified RENAL Score (OR 1.29, 95 % C.I. 1.09-1.53, p = 0.003) and clinical tumor size (OR 1.16, 95 % C.I. 1.10-1.22, p < 0.01) as upstaging predictors, confirmed by multivariable analysis (p < 0.01).

CONCLUSION

Our comparative analysis found no worsened perioperative or adverse pathological outcomes in patients with deferred PN, supporting the safety of this approach in managing SRMs, at least as an initial option.

Construction of a Model for Predicting the Risk of pT3 Based on Perioperative Characteristics in cT1 Renal Cell Carcinoma: A Retrospective Study at a Single Institution

INTRODUCTION

This study explored the predictors of upstaging and multiple sites of extension, and constructed a predictive model based on perioperative characteristics to calculate the risk of upstaging of cT1 renal cell carcinoma to pT3.

METHODS

We retrospectively reviewed 1012 patients diagnosed with cT1 renal cell carcinoma who underwent surgical treatment at the Affiliated Hospital of Qingdao University between June 2016 and August 2021. The continuous and categorical variables were analyzed using the Mann-Whitney U test and Chi-square test, respectively. After randomly dividing patients into a training set and an internal validation set with a ratio of 7:3, univariate and multivariate logistic regression analyses were used to explore the predictors of upstaging and multiple sites of extension. A nomogram model was established based on the predictors of upstaging and was validated.

RESULTS

Ninety-one cases (8.99%) of renal cell carcinoma were upstaged to pT3. In the training set, multivariate logistic regression identified the following predictors of upstaging: maximum tumor diameter, hilus involvement, tumor necrosis, tumor edge irregularity, symptoms, smoking, and platelet-lymphocyte ratio. A nomogram model was established based on the predictors. The area under the receiver operating characteristic curve was 0.810 in the training set, and 0.804 in the validation set. A 10-fold internal cross-validation conducted 200 times showed that the mean area under the curve was 0.797. The calibration curve and decision curve analysis suggested that the nomogram had robust clinical predictive power. Analyses showed higher neutrophil-lymphocyte ratio and tumor necrosis were associated with multiple sites of extrarenal extension in patients with pT3a renal cell carcinoma.

CONCLUSIONS

We identified 7 predictors of upstaging to pT3 and 2 predictors of multiple sites of extension. A nomogram model was constructed with satisfactory accuracy for predicting upstaging to pT3.

Percutaneous ablation versus robotic‑assisted partial nephrectomy for cT1 renal cell carcinoma: an evidence-based analysis of comparative outcomes

This investigation sought to conduct a comprehensive meta-analysis to assess the comparative effectiveness and safety of percutaneous ablation (PCA) versus robotic-assisted partial nephrectomy (RAPN) among individuals diagnosed with cT1 renal tumors. This study rigorously followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to conduct a systematic review and meta-analysis. A systematic search was carried out in the PubMed, Embase, Web of Science, and Cochrane Library databases, focusing on studies published in English through February 2024. We focused on evaluating primary outcomes, specifically perioperative outcomes, functional outcomes, and oncological outcomes. In this analysis, data from 1534 patients across 13 studies were evaluated. PCA was found to have advantageous outcomes in comparison to RAPN regarding hospital stay durations, with a Weighted Mean Difference (WMD) of - 2.03 days (95% Confidence Interval [CI]: -3.78 to - 0.27; p = 0.02), operative times (WMD: -106.75 min; 95% CI: - 170.78 to - 42.72; p = 0.001), and overall complication rates (Odds Ratio [OR]: 0.61; 95% CI: 0.42 to 0.89; p = 0.01). Conversely, PCA showed a higher incidence of local recurrence compared to RAPN, with an OR of 3.20 (95% CI: 1.91 to 5.35; p < 0.00001). Moreover, there were no statistically significant differences between the two treatments in terms of major complications, declines in estimated glomerular filtration rates (eGFR), variations in creatinine levels, overall survival rates, and recurrence-free survival. While PCA exhibits higher local recurrence rates than RAPN, it also presents significant advantages, such as shorter hospital stays, decreased operative durations, and lower complication rates. This juxtaposition underscores the urgent need for further, more rigorous research to substantiate these findings.

ctDNA predicts clinical T1a to pathological T3a upstaging after partial nephrectomy

Most patients diagnosed with clear cell renal cell carcinoma (ccRCC) are also detected with small and organ-confined tumors, and the majority of these are classified as clinical tumor stage 1a (cT1a). A considerable proportion of patients with cT1 RCC shows tumor upstaging to pathological stage 3a (pT3a), and these patients have worse oncological outcomes. The role of circulating tumor DNA (ctDNA) in RCC has been limited to monitoring treatment response and resistance. Therefore, the present study aimed to evaluate the potential of ctDNA in predicting pT3a upstaging in cT1a ccRCC. We sequenced plasma samples preoperatively collected from 48 patients who had undergone partial nephrectomy for cT1a ccRCC using data from a prospective cohort RCC. The ctDNA were profiled and compared with clinicopathological ccRCC features to predict pT3a upstaging. Associations between ctDNA, tumor complexity, and pT3a upstaging were evaluated. Tumor complexity was assessed using the anatomical classification system. Univariate analysis used chi-squared and Student's t-tests; multivariate analysis considered significant factors from univariate analyses. Of the 48 patients with cT1a ccRCC, 12 (25%) were upstaged to pT3a, with ctDNA detected in 10 (20.8%), predominantly in patients with renal sinus fat invasion (SFI; n = 8). Among the pT3a group, ctDNA was detected in 75%, contrasting with only 2.8% in patients with pT1a (1/36). Detection of ctDNA was the only significant preoperative predictor of pT3a upstaging, especially in SFI. This study is the first to suggest ctDNA as a preoperative predictor of pT3a RCC upstaging from cT1a based on preoperative radiological images.

Outcomes and predictors of clinical T1 renal mass (cT1) upstaged to pathological T3a (pT3a) after partial nephrectomy: A single-center experience

OBJECTIVES

Clinical T1 (cT1) renal mass treated surgically has a good prognosis, but there is an upstaging risk that potentially threatens oncological outcomes after partial nephrectomy (PN). We aim to analyze and study the incidence, predictors, perioperative morbidity, and oncological outcomes of pT3a upstaging.

METHODOLOGY

A retrospective study of 313 patients who underwent PN for cT1 renal mass at a single center from a single tertiary referral center between 2000 and 2021 was done. Demographic, perioperative, pathological, and outcome variables were reviewed. We compared these parameters between upstaged and non-upstaged groups. Multivariate logistic regression analysis was used to study preoperative variables associated with upstaging.

RESULTS

Nineteen patients were upstaged to pT3a. Making an incidence of 6.1%. Upstaged tumors were bigger (5.02 cm vs. 4.08 cm, p = 0.004), had higher clinical stage T1b (84.2 vs. 40.5%, p < 0.001), had more tumors which were central location (21 vs. 3.4%, p < 0.001), had more endophytic and mesophytic tumors (15.8 vs. 5.8% and 52.6 vs. 9.5%, p < 0.001), and had higher R.E.N.A.L Nephrometry score (8.05 vs. 6, p < 0.001). Upstaged tumors had more operative times (227 vs. 203 min, p = 0.01), more postoperative complications (68.4 vs. 13.1%, p < 0.001), more major complications of Clavien Dindo Grade 3 and above (15.8 vs. 4.4%, p < 0.001). Age (OR 1.035, p = 0.034), Radiological tumor dimension (OR 1.578, p = 0.003), Radiological or Clinical stage (T1b) (9.19, p = 0.008), Higher Nephrometry score (Intermediate and High) (OR 6.184, p = 0.004) were preoperative predictors of upstaging. Oncological outcomes were comparable.

CONCLUSION

Tumor upstaging was uncommon with more perioperative morbidity. Higher age, larger tumor size, higher tumor stage, and higher nephrometry scores were preoperative predictors of upstaging.

Patient and tumor characteristics of histological subtypes of renal cell carcinoma and its risk of upstaging to ≥pT3

OBJECTIVE

To explore how histological subtypes impact upstaging to nonorgan confined renal cell carcinoma (≥pT3 RCC) in patients treated with partial/radical nephrectomy for cT1-2 RCC.

MATERIALS AND METHODS

We relied on an institutional tertiary-care database to identify RCC patients treated with partial/radical nephrectomy between January 2002 and December 2021. Patients were stratified according to histological subtype of RCC. Upstaging was defined as any cT1-2 tumor classified as ≥pT3 at final pathology. Uni- and multivariable logistic regression models were fitted to predict upstaging.

RESULTS

Of overall 1,020 surgically treated RCC patients, 743 harbored clear-cell (72.8%) vs. 193 (18.9%) papillary vs. 49 (4.8%) chromophobe vs. each 4 (0.4%) collecting duct and sarcomatoid vs. 27 (2.6%) other/mixed pathology of RCC. Median tumor size ranged from 3.0 cm (mixed RCC) to 7.7 cm (sarcomatoid RCC). In total, upstaging rate to ≥pT3 was 22% and ranged from 6.1% (chromophobe RCC) to 75% (collecting duct RCC). In univariable logistic regression models, chromophobe and papillary histological subtypes were significantly associated with lower upstaging of all cT1-2 RCC tumors. After controlling for patient and tumor characteristics in multivariable logistic regression models, papillary RCC independently lowers the risk of upstaging, even in sensitivity analyses for cT1 RCC only.

CONCLUSION

Important differences between histological subtypes of RCC exist regarding characteristics such as stage and tumor size at presentation, as well as upstaging to ≥pT3 at final pathology. Specifically, papillary RCC is significantly associated with lower chance of upstaging even after controlling for confounding parameters. The study is limited by missing central pathological/radiographic review and lack of survival analyses.

Prognostic features of upstaged pT3a renal tumors with fat invasion after robot-assisted partial nephrectomy: is it time for a new subclassification?

INTRODUCTION

The clinical management of pT3a pathologic-upstaged renal cell carcinoma (RCC) patients is actually controversial. Aim of this study was i) to assess the impact of pT3a upstaging on oncologic outcomes after robot-assisted partial nephrectomy (RAPN) for cT1-T2 RCC; ii) to explore clinical and surgical predictors of pT3a upstaging; iii) to evaluate the differential impact of perinephric fat invasion (PFI) or sinus fat invasion (SFI) on survival outcomes after RAPN in case of upstaged pT3a RCC.

MATERIALS AND METHODS

Clinical and surgical data from consecutive RCCs treated with RAPN in a single referral centre between January 2017 and June 2021 were prospectively collected and retrospectively reviewed. Pathological upstaging to pT3a tumors with fat invasion was further stratified in SFI or PFI. Uni- and multivariable analysis were fitted to explore clinical and surgical predictors of disease recurrence.

RESULTS

Overall, 1852 patients were enrolled and 179 (9.7%) with pT3a upstaging were found. Median age was 65 (IQR 56-73) years with a median BMI of 25.6 (23.6-29.0). At a median follow up of 26 (9-38) months, 76 (4.1%) patients showed disease recurrence. Multivariable analysis confirmed PADUA score ≥10 (OR 1.76, CI 95% 1.18-1.91, p = 0.001), age at surgery (OR 1.04, CI 95% 1.01-1.06, p = 0.01), clinical tumor diameter (OR 1.31, CI 95% 1.17-1.47, p = 0.001), tumor necrosis (OR 1.54, CI 95% 1.08-1.88, p = 0.001) and nucleolar grading ≥3 (OR 1.27, CI 95% 1.01-1.44, p = 0.001) as independent predictors of pT3a upstaging. Multivariate Cox regression model showed pathological sinus fat invasion as an independent predictor of disease recurrence (HR 3.43, CI 95% 1.51-7.77, p = 0.003) in pT3a upstaged group.

CONCLUSION

In pathologically upstaged pT3a RCCs, sinus fat invasion was confirmed as independent predictor of disease relapse. In this light, the definition of novel risk categories in the pT3a patients setting should be encouraged.

An external validation of the nocera nomogram: Predicting non-organ confined stage of ≥pT3 in cT1 clear cell renal cell carcinoma

Background

Only one previously published study by Nocera et al. addressed the risk of upstaging to ≥pT3 in cT1 clear cell renal cell carcinoma (ccRCC) by using characteristics of the R.E.N.A.L and PADUA score (age, tumor size, rim location, exophytic rate, polar involvement) developing an accurate nomogram. However, this nomogram has never been externally validated yet.

Material and methods

The study cohort consisted of 288 patients with cT1a-b ccRCC, diagnosed between 2008-2021 at the University Hospital Frankfurt, Germany. Analyses addressed clinical, tumor and radiographic characteristics. The external validation of the nomogram relied on accuracy calculations derived from the area under the curve of the receiver operator characteristic analysis.

Results

Overall, 11.8% (n=34) patients harbored ≥pT3 ccRCC. Median radiographic tumor size (3.6 vs. 5.3cm), R.E.N.A.L. (8 vs. 9 points) and PADUA score (9 vs. 11 points), as well as proportions of renal sinus involvement (82.4% vs. 51.6%), renal hilus involvement (44.1 vs. 13.0%), and medial rim location significantly differed between the pT1-2 and ≥pT3 group (all p ≤ 0.01). In subgroup analyses of small renal mass ccRCC patients (<4cm, cT1a), only 3.8% (n=6) patients had ≥pT3 pathology. Upstaged patients were significantly older and more frequently had endophytic tumor than pT1-2 counterparts (p<0.05). The external validation of the Nocera nomogram showed a good accuracy of 76.6%. Using the suggested cut-off of 21%, 26.5% of patients exhibited ≥pT3 ccRCC. Conversely, within patients below cut-off, 5.9% patients exhibited ≥pT3 ccRCC.

Conclusion

We reported the first external validation of the nomogram addressing the risk of ≥pT3 in cT1 ccRCC patients, demonstrating a good accuracy, with a low false-negative rate. Therefore, the nomogram can accurately be used for patients’ counselling and treatment decision making.

Partial vs. radical nephrectomy in non-metastatic pT3a kidney cancer patients: a population-based study

BACKGROUND

To test for differences in cancer specific mortality (CSM) rates between radical nephrectomy (RN) and partial nephrectomy (PN) in pT3a nmRCC patients.

METHODS

Within the Surveillance, Epidemiology, and End Results database (2005-2016), 13,177 pT3a patients treated with either PN or RN were identified. Before and after 1:2 ratio propensity score (PS)-match between PN and RN patients, cumulative incidence plot and competing risks regression (CRR) were used to test differences in CSM and other cause mortality (OCM) rates.

RESULTS

Relative to PN (n=1,615, 22.5%), RN patients harbored higher tumor size (72 vs. 38 mm; >70 mm 51 vs.10%), of more aggressive histology, collecting duct (0.4 vs. 0.2%) and sarcomatoid (2.3 vs.0.8%), of higher grade (51.0 vs. 37.5%). After PS-matching and OCM adjustment, 5-year CSM was 3-fold higher after RN than PN (p<0.01). Similarly, after PS matching and CSM adjustment, also 5-year OCM rates were higher after RN (HR: 1.59, p=0.0003).

CONCLUSIONS

PN does not appear to compromise the oncological outcomes in patients with pT3a or high-grade renal masses when compared with RN. Therefore, these concerns should not deter a surgeon from attempting PN when otherwise technically feasible.

Integrative Analysis of Peripheral Blood Indices for the Renal Sinus Invasion Prediction of T1 Renal Cell Carcinoma: An Ensemble Study Using Machine Learning-Assisted Decision-Support Models

Purpose

Renal sinus invasion is an attributive factor affecting the prognosis of renal cell carcinoma (RCC). This study aimed to construct a risk prediction model that could stratify patients with RCC and predict renal sinus invasion with the help of a machine learning (ML) algorithm.

Patients and Methods

We retrospectively recruited 1229 patients diagnosed with T1 stage RCC at the Baotou Cancer Hospital between November 2013 and August 2021. Iterative analysis was used to screen out predictors related to renal sinus invasion, after which ML-based models were developed to predict renal sinus invasion in patients with T1 stage RCC. The receiver operating characteristic curve (ROC), decision curve analysis (DCA), and clinical impact curve (CIC) were performed to evaluate the robustness and clinical practicability of each model.

Results

A total of 21 candidate variables were shortlisted for model building. Iterative analysis screened that neutrophil to albumin ratio (NAR), hemoglobin level * albumin level * lymphocyte count/platelet count ratio (HALP), prognostic nutrition index (PNI), body mass index*serum albumin/neutrophil-lymphocyte ratio (AKI), NAR, and fibrinogen (FIB) concentration (NARFIB), platelet to lymphocyte ratio (PLR), and R.E.N.A.L score was related to renal sinus invasion and contributed significantly to ML-based algorithm. The areas under the ROC curve (AUCs) of the random forest classifier (RFC) model, support vector machine (SVM), eXtreme gradient boosting (XGBoost), artificial neural network (ANN), and decision tree (DT) ranged from 0.797 to 0.924. The optimal risk probability of renal sinus invasion predicted was RFC (AUC = 0.924, 95% confidence interval [CI]: 0.414–1.434), which showed robust discrimination for identifying high-risk patients.

Conclusion

We successfully develop practical models for renal sinus invasion prediction, particularly the RFC, which could contribute to early detection via integrating systemic inflammatory factors and nutritional parameters.

Comparison and development of preoperative systemic inflammation markers-based models for the prediction of unfavorable pathology in newly diagnosed clinical T1 renal cell carcinoma

BACKGROUND

We sought to investigate the preoperative risk factors associated with the unfavorable pathology (UP) of clinical T1 (cT1) renal lesions. The aims of this study were to develop and compare several novel models capable of accurately identifying those patients at high risk of harboring occult adverse histopathological characteristics.

METHODS

The clinical parameters and preoperative laboratory test results from 1281 cT1 renal cell carcinomas (RCCs) patients who underwent partial nephrectomy (PN) or radical nephrectomy (RN) were collected. The data was randomly split into training (70%) and testing (30%) datasets. We performed univariable and multivariable logistic regression analyses for significant predictors and, subsequently, constructed predictive models based on those significant risk factors. Receiver operating characteristic (ROC) analysis was used to determine the model with the highest discrimination power with corresponding area under the curve (AUC). Calibration curves were plotted and decision curve analyses (DCAs) were applied to explore clinical net benefit.

RESULTS

UP was identified in 21.1% (n = 270), 21.0% (n = 188) and 21.3% (n = 82) patients in the total population, training cohort and validation cohort, respectively. R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, location relative to the polar lines) nephrometry score, tumor size, neutrophil-to-lymphocyte ratio (NLR) and albumin-to-globulin ratio (AGR) were independent predictors of UP. Among those predictive models, the model that consisted of tumor size, hemoglobin, NLR and AGR performs best according to the highest AUC of 0.70 and the highest net benefit. When tumor histology was added to the biomarker-based model, including tumor size, hemoglobin, NLR and AGR, the AUC improved from 0.60 to 0.63 in the validation cohort.

CONCLUSIONS

In this analytical model study, our findings verified that systemic inflammation response markers showed high potential for identifying UP. Our biomarker-based models well predicted occult aggressive histopathological characteristics among patients with cT1 renal lesions, and the use of models may be greatly beneficial to urologists in tailoring precise management and therapy for patients. Robust validation is warranted prior to adoption into clinical practice.

Added Value of Systemic Inflammation Markers in Predicting Clinical Stage T1 Renal Cell Carcinoma Pathologically Upstaged to T3a

Objectives

We aimed to determine preoperative risk factors associated with pathologic T3a (pT3a) upstaging of clinical T1 (cT1) renal cell carcinomas (RCCs) and develop a novel model capable of accurately identifying those patients at high risk of harboring occult pT3a characteristics.

Methods

A retrospective analysis of 1324 cT1 RCC patients who underwent partial nephrectomy (PN) or radical nephrectomy (RN) was performed. The study cohort was divided into training and testing datasets in a 70:30 ratio for further analysis. Univariable and multivariable logistic regression analyses were performed to identify predictors associated with cT1 to pT3a upstaging and subsequently, those significant risk factors were used to construct models. We used the area under the curve (AUC) to determine the model with the highest discrimination power. Decision curve analyses (DCAs) were applied to evaluate clinical net benefit associated with using the predictive models.

Results

The rates of upstaging were 6.1% (n = 81), 5.8% (n = 54) and 6.8% (n = 27) in the total population, training cohort and validation cohort, respectively. Tumor size, clinical T stage, R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior) nephrometry score, lymphocyte to monocyte ratio (LMR), prognostic nutrition index (PNI) and albumin to globulin ratio (AGR) were significantly associated with pT3a upstaging. The model that consisted of R.E.N.A.L. score, LMR, AGR and PNI achieved the highest AUC of 0.70 in the validation cohort and yielded the highest net benefit. In the subpopulation with complete serum lipid profile, the inclusion of low-density lipoprotein cholesterol (LDL-C) and Castelli risk index-I (CRI-I) significantly improved the discrimination of model (AUC = 0.86).

Conclusions

Our finding highlights the importance of systemic inflammation response markers and serum lipid parameters in predicting pT3a upstaging. Our model had relatively good discrimination in predicting occult pT3a disease among patients with cT1 renal lesions, and the use of the model may be greatly beneficial to urologists in risk stratification and management decisions.

Computed tomography features predicting aggressiveness of malignant parenchymal renal tumors suitable for partial nephrectomy

The aim of this study was to identify and standardize computed tomography (CT) features having a potential role in predicting aggressiveness of malignant parenchymal renal tumors suitable for partial nephrectomy (PN). We performed a non-systematic review of the recent literature to evaluate the potential impact of CT variables proposed by the Society of Abdominal Radiology Disease-Focused Panel on Renal Cell Carcinoma in predicting aggressiveness of newly diagnosed malignant parenchymal renal tumors. The analyzed variables were clinical tumor size, tumor growth rate, enhancement characteristics, amount of cystic component, polar and capsular location, tumor margins and distance between tumor and renal sinus. Unfavorable behavior was defined as: 1) renal cell carcinoma (RCC) with stage ≥pT3; 2) nuclear grade 3 or 4; 3) presence of sarcomatoid de-differentiation; or 4) non-clear cell subtypes with unfavorable prognosis (type 2 papillary RCC, collecting duct or renal medullary carcinoma, unclassified RCC). Beyond clinical tumor size, tumor growth rate, enhancement characteristics, amount of cystic component, tumor margins and distance between tumor and renal sinus are highly relevant features predicting an unfavorable behavior. Moreover, several studies supported the role of necrosis as preoperative predictor of tumor aggressiveness. Peritumoral and intratumoral vasculature as well as capsule status are emerging variables that need to be further evaluated. Tumor size, enhancement characteristics, tumor margins and distance to the renal sinus are highly relevant CT features predicting biological aggressiveness of malignant parenchymal renal tumors. Combination of these parameters might be useful to generate tools to predict the unfavorable behavior of renal tumors suitable for PN.

Predicting the risk of pT3a stage in cT1 clear cell renal cell carcinoma

We hypothesized that pT3a stage at nephrectomy can be accurately predicted in cT1N0M0 clear cell-renal cell carcinoma (cc-RCC) patients. Of 236 patients, treated with either partial or radical nephrectomy (2005-2019), 25 (10.6%) harbored pT3a stage. Multivariable logistic regression models predicting pT3a were fitted using age, tumor size, tumor location and exophytic rate. The new model was 81% accurate. In calibration plots, minimal departures from ideal prediction were recorded. In decision curve analyses, a net-benefit throughout all threshold probabilities was recorded relative to the treat-all or treat-none strategies. Using a probability cut-off of 21% for presence of pT3a stage, 38 patients (16.1%) were identified, in whom pT3a rate was 36.8%. Conversely, in 198 patients (83.9%) below that cut-off, the rate of pT3a was 5.6%. Alternative user-defined cut-offs may be selected. The new model more accurately identifies a subgroup of cT1N0M0 cc-RCC patients with substantially higher risk of pT3a stage than average.

Upstaging to pT3a in Patients Undergoing Partial or Radical Nephrectomy for cT1 Renal Tumors: A Systematic Review and Meta-analysis of Outcomes and Predictive Factors

CONTEXT

Predictors of upstaging from cT1 to pT3a renal masses are poorly inquired, and this remains an area of controversial findings.

OBJECTIVE

To evaluate predictors and outcomes of upstaging from cT1 to pT3a in patients undergoing surgical removal of a renal tumor.

EVIDENCE ACQUISITION

A systematic literature search was performed to identify relevant articles using three electronic engines (PubMed, Embase, and Web of Science). Only studies looking at upstaging to pT3a in patients undergoing either partial nephrectomy (PN) or radical nephrectomy (RN) for cT1 renal tumor were included. Study selection was performed according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement.

EVIDENCE SYNTHESIS

Thirteen studies, including 21869 patients (cT1/pT3a: 1256 [5.7%]; cT1/pT1: 20613 [93.3%]), were identified. Patients in the upstaged group were older (weighted mean difference [WMD]: 3.89; p < 0.00001) and mostly male (odds ratio [OR]: 1.23; p = 0.04). Renal tumors were larger (WMD: 0.98; p < 0.00001), more complex (OR: 2.38; p < 0.0001), and with a higher rate of cT1b masses (OR: 3.36; p < 0.00001). The cT1/pT3a group had a higher rate of other renal cell carcinoma histological subtypes (OR: 1.59; p = 0.04), as well as higher odds of Fuhrman grade ≥3 (OR: 2.57; p < 0.00001) and positive surgical margins (OR: 1.85; p = 0.007). Five-year recurrence-free survival (RFS) was worse in the upstaged group (OR: 0.31; p = 0.02). Age (OR: 1.03; p < 0.00001), tumor size (OR: 1.51; p < 0.00001), and RENAL score (OR: 2.80; p = 0.0004) were predictors of upstaging. Upstaging was associated with overall survival (hazard ratio [HR]: 1.94; p = 0.05), cancer-specific survival (HR: 2.24; p = 0.007), and RFS (HR: 2.17; p < 0.00001).

CONCLUSIONS

Upstaging to pT3a in case of surgical removal of a cT1 renal tumor is an uncommon event, which however can translate into worse oncological outcomes. Both patient (older age) and tumor (larger size and higher complexity) characteristics are associated with a higher risk of upstaging. There is very limited evidence regarding whether RN would be better than PN in these cases. There remains an unmet need for tools to better characterize renal masses in the preoperative setting.

PATIENTS SUMMARY

About 6% of surgically treated localized renal tumors can be found to be locally advanced on final pathology after surgery. This "upstaging" can translate into worse oncological outcomes. There are patient and tumor characteristics that are associated with an increased the risk of upstaging.

A preoperative model to predict pT3 upstaging in clinically localized renal cell carcinoma

Introduction

Patients upstaged to pT3 after partial nephrectomy (PN) may be at an increased risk of disease progression compared to those patients submitted to radical nephrectomy (RN). We sought to identify preoperative factors predicting pT3 upstaging in localized renal cell carcinoma.

Material and methods

Patients submitted to nephrectomy for clinically localized (cT1–cT2) renal cell carcinoma between 2011 and 2016 were identified from a prospective registry, those presenting with locally advanced or metastatic disease were excluded. Clinical factors, laboratory, and imaging using RENAL score, were analyzed. A multivariate analysis was performed looking for stage pT3a predictors.

Results

Two hundred and nine patients were included, 66% were men, with a mean age of 57 years. Mean tumor size was 49 ±31 mm. 19% were staged as pT3a. Of this group, 10% underwent a PN. Age, hypertension, presence of hematuria, creatinine levels, size and RENAL score were statistically associated with locally advanced stage. The variables of the RENAL score that were associated to pT3a stage were size, nearness to renal sinus/collector system and contact with main renal vessels. On the multivariate analysis, only age, size, and contact with renal vessels were found to predict upstaging. A model was developed which was able to predict stage pT3a with an area under the curve (AUC) of 0.864 in the ROC curve.

Conclusions

Upstaging to pT3a is fairly common in clinically localized tumors. A formula that includes tumor size, age and contact with the main vessels on imaging, can help predict it. This should be considered when deciding if the patient is a candidate for nephron sparing surgery.