Mayo Adhesive Probability Score Is Associated With Localized Renal Cell Carcinoma Progression-free Survival

The Role of Perirenal Adipose Tissue in Carcinogenesis-From Molecular Mechanism to Therapeutic Perspectives

Perirenal adipose tissue (PRAT) exhibits particular morphological features, with its activity being mainly related to thermogenesis. However, an expanded PRAT area seems to play a significant role in cardiovascular diseases, diabetes mellitus, and chronic kidney disease pathogenesis. Numerous studies have demonstrated that PRAT may support cancer progression and invasion, mainly in obese patients. The mechanism underlying these processes is of dysregulation of PRAT's secretion of adipokines and pro-inflammatory cytokines, such as leptin, adiponectin, chemerin, apelin, omentin-1, vistatin, nesfatin-1, and other pro-inflammatory cytokines, modulated by tumor cells. Cancer cells may also induce a metabolic reprogramming of perirenal adipocytes, leading to increased lipids and lactate transfer to the tumor microenvironment, contributing to cancer growth in a hypoxic milieu. In addition, the PRAT browning process has been specifically detected in renal cell carcinoma (RCC), being characterized by upregulated expression of brown/beige adipocytes markers (UCP1, PPAR-ɣ, c/EBPα, and PGC1α) and downregulated white fat cells markers, such as LEPTIN, SHOX2, HOXC8, and HOXC9. Considering its multifaceted role in cancer, modulation of PRAT's role in tumor progression may open new directions for oncologic therapy improvement. Considering the increasing evidence of the relationship between PRAT and tumor cells, our review aims to provide a comprehensive analysis of the perirenal adipocytes' impact on tumor progression and metastasis.

Predicting post-surgical complications using renal scoring systems

Current surgical approaches for renal malignancies primarily rely on qualitative factors such as patient preferences, surgeon experience, and hospital capabilities. Applying a quantitative method for consistent and reliable assessment of renal lesions would significantly enhance surgical decision-making and facilitate data comparison. Nephrometry scoring (NS) systems systematically evaluate and describe renal tumors based on their anatomical features. These scoring systems, including R.E.N.A.L., PADUA, MAP scores, C-index, CSA, and T-index, aim to predict surgical complications by evaluating anatomical and patient-specific factors. In this review paper, we explore the components and methodologies of these scoring systems, compare their effectiveness and limitations, and discuss their application in advancing patient care and optimizing surgical outcomes.

The impact of Mayo Adhesion probability score on the success of extracorporeal shock wave lithotripsy for kidney stones

Urolithiasis is a prevalent condition in urology, with extracorporeal shock wave lithotripsy (ESWL) serving as a common treatment for kidney stones under 2 cm. The Mayo Adhesion Probability (MAP) score, calculated from perinephric fat characteristics, is traditionally used to assess surgical outcomes but has not been explored in the context of ESWL. This study aims to evaluate the effect of MAP score on the success rate of ESWL. This retrospective study included patients who underwent ESWL for kidney stones between January 2018 and June 2024 at a tertiary care center. Demographic data, stone characteristics, and MAP scores were obtained through CT imaging. ESWL success was defined as either complete stone clearance or a residual fragment less than 4 mm at three months post-procedure. Logistic regression and ROC analysis were employed to identify predictors of treatment success and to determine the optimal MAP score cutoff. A total of 260 patients were analyzed, divided into two groups: MAP score < 3 (n = 154) and MAP score ≥ 3 (n = 106). Patients with a MAP score ≥ 3 had a significantly lower ESWL success rate (49.1%) compared to those with a MAP score < 3 (71.4%; p = 0.001). Multivariate analysis identified MAP score, BMI, and stone size as significant predictors of ESWL success. ROC analysis established a MAP score cutoff of 2, with 76.5% sensitivity and 64.3% specificity. The MAP score is an independent predictor of ESWL success in kidney stone treatment. Preoperative MAP evaluation may improve patient selection and optimize ESWL outcomes.

The relationship between map scores and complications after standard percutaneous nephrolithotomy

PURPOSE

Upper urinary tract stones are a common condition in urology clinics. Percutaneous nephrolithotomy (PCNL) is an effective procedure frequently used for the treatment of stones larger than 2 cm. MAP scoring is used to predict oncological outcomes and intraoperative complications after partial nephrectomy by using the thickness and adhesion of perinephric adipose tissue. We examined the relationship between MAP score and clinical and demographic findings of the patients, especially postoperative Hgb drop and postoperative complications.

MATERIAL-METHOD

Patients were divided into 2 groups: Those with MAP score < 3 and ≥ 3. The impact of the MAP score on the demographic, clinical, and surgical parameters of the groups was assessed and analyzed. The relationship between MAP score and complications based on Clavien Dindo classification was also examined. The study investigated factors affecting the development of complications, the amount of bleeding, and the influence of MAP scores on these outcomes.

RESULTS

The Hgb drop was 2.56 ± 1.00 in the group with a MAP score ≥ 3 which was statistically significantly higher than the group with a MAP score < 3 (1.43 ± 1.21) (p < 0.001). The stone-free rate was 81.7% in the group with a MAP score < 3, which was statistically significantly higher than the group with a MAP score ≥ 3 (59.6%) (p = 0.012).

CONCLUSION

As the MAP score of patients scheduled for standard PNL operation increased, there was a corresponding rise in Hgb drop, a decline in stone-free rates and an uptick in postoperative urinary complications of postoperative urinary infections.

The predictive ability of Mayo adhesive probability score for evaluating intraoperative bleeding in standard percutaneous nephrolithotomy in adult patients

Mayo adhesive probability (MAP) score is one of the commonest tool to predict the adherence status of perirenal fat. The association between MAP score and intraoperative hemorrhage in patients undergoing micropercutaneous nephrolithotomy was comfirmed in a recent well designed study. We aimed to investigate if MAP score may predict the possibility for significant intraoperative bleeding in supine percutaneous nephrolithotomy (PCNL) performed with a 26 Fr rigid nephroscope. In this observational retrospective study, demographic, clinical, laboratory, radiological, perioperative (operation duration, hospitalization, intraoperative bleeding, success) and MAP score (perinephric fat stranding, posterior perinephric fat thickness and total MAP score) data of all patients who underwent supine PCNL between June 2021 and July 2023 were evaluated. The patients were divided into 2 groups according to their MAP scores (79 [54.1%] patients with MAP score < 3 [low MAP score] and 67 [54.1%] patients with MAP score ≥ 3 [high MAP score]). The rate of patients with intraoperative bleeding was 47.8% in the patient group with a high MAP score, while it was 22.8% in the patient group with a low MAP score (p = 0.002). In multivariate logistic regression analysis, anticoagulant drug use history (OR = 2.525; 95% CI = 1.025-6.224; p = 0.044), presence of multiple stones (OR = 3.015; 95% CI = 1.205-7.543; p = 0.018), calyx localization of the stone (OR = 2.871;95% CI = 1.166-7.068; p = 0.022), higher renal parenchymal thickness (OR = 1.119; 95% CI = 1.049-1.193; p = 0.001) and MAP score > 3 (OR = 3.486; 95% CI = 1.579-7.696; p = 0.002) were defined as independent risk factors for significant intraoperative bleeding. In clinical practice, the MAP score can be used to predict bleeding before PCNL.

[Nephron sparing in the management of localized solid renal mass]

Managing a malignant renal tumor requires, first of all, a reflection on the necessity of its treatment. It must consider the renal function, altered at the time of diagnosis in 50% of cases. The treatment method chosen depends on many factors, in particular, the predicted residual renal function, the risk of chronic kidney disease, the need for temporary or long-term dialysis, and overall long-term survival. Other factors include the size, position, and number of tumors and a hereditary tumor background. When a renal-sparing management alternative is available, total nephrectomy should no longer be performed in patients with small malignant renal masses (cT1a). This may consist of surgery (partial nephrectomy or lumpectomy), percutaneous thermo-ablation (by radiofrequency, microwave, or cryotherapy). In patients with limited life expectancy, imaging-based surveillance may be proposed to suggest treatment in case of local progression. Good coordination between urologist, radiologist, nephrologist, and sometimes radiotherapist should allow optimal management of patients with a malignant renal tumor with or without underlying renal failure.

Prognostic value of preoperative radiographic perinephric fat features in renal cell carcinoma patients undergoing surgery

BACKGROUND

We aimed to assess the prognostic importance of perinephric fat features in images of patients with non-metastatic renal cell carcinoma (RCC) undergoing surgery.

METHODS

We enrolled RCC patients who underwent surgical treatment between 2011 and 2019. Two characteristics, including perinephric fat thickness and perinephric fat stranding, were evaluated using preoperative computed tomography or magnetic resonance images. The association between perinephric fat characteristics and disease progression was examined by Kaplan-Meier survival analysis and Cox regression model.

RESULTS

In a multivariate Cox proportional hazards model adjusting for tumor stage, intratumoral necrosis, and neutrophil-to-lymphocyte ratio, we found that patients in the thin perinephric fat group (<1 cm) had a poorer progression-free survival (PFS) compared to the thick perinephric fat group (≥1 cm) (HR 2.8; 95% CI 1.175-6.674, p = 0.02). Additionally, the fat stranding group had a poorer PFS than the non-stranding group (HR 3.852; 95% CI 1.082-13.704, p = 0.037). The non-stranding with thick perinephric fat group exhibits the highest cumulative PFS while the stranding with thin perinephric fat group has the lowest cumulative PFS. In receiver operating characteristic curve analysis, combing these two perinephric fat characteristics with tumor stage can achieve a better discriminatory power than tumor stage alone.

CONCLUSIONS

Our study indicates that the evaluation of image-based perinephric fat features is a simple, straightforward, reproducible tool for predicting RCC prognosis and may assist in preoperative risk stratification.

A Review of the Paradigmatic Role of Adipose Tissue in Renal Cancer: Fat Measurement and Tumor Behavior Features

(1) Background: Renal-cell carcinoma (RCC) incidence has been steadily rising, with obesity identified as a potential risk factor. However, the relationship between obesity and RCC prognosis remains unclear. This systematic review aims to investigate the impact of different adipose tissue measurements on RCC behavior and prognosis. (2) Methods: A search of MEDLINE databases identified 20 eligible studies focusing on various fat measurements, including visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), perirenal adipose tissue (PRAT), and the Mayo adhesive probability (MAP) score. (3) Results: The review revealed conflicting findings regarding the association between adipose tissue measurements and RCC outcomes. While some studies suggested a protective role of certain fat deposits, particularly VAT, against disease progression and mortality, others reported contradictory results across different adipose metrics and RCC subtypes. (4) Conclusions: Methodological variations and limitations, such as retrospective designs and sample size constraints, pose challenges to standardization and generalizability. Further research is needed to understand these associations better and establish standardized approaches for adiposity assessment in RCC patients, which could inform clinical practice and therapeutic decision-making.

The Mayo adhesive probability score predicts postoperative fever and intraoperative hemorrhage in mini-percutaneous nephrolithotomy

PURPOSE

Contemporary predictive tools for miniaturized percutaneous nephrolithotomy (mPCNL) mainly focus on stone clearance but not perioperative complications, especially infection and hemorrhage. This study aimed to evaluate whether the Mayo adhesive probability (MAP) score, an index of the perinephric fat characteristics, can predict postoperative fever and intraoperative hemorrhage in mPCNL.

METHODS

This is a retrospective study recruiting 159 mPCNL patients from July 2018 to January 2022. MAP scores were recorded using preoperative computed tomography. Postoperative complications included postoperative fever and intraoperative bleeding, defined as hemoglobin drop.

RESULTS

Over half patients had the MAP score ≧ 3. Men, elderly, chronic kidney disease, and diabetes were associated with a higher MAP score. The patients with a higher MAP score were more likely to have postoperative fever after mPCNL. On multivariate analysis, preoperative positive urine culture (OR 2.68) and a higher MAP score (OR 2.28) were both significantly associated with postoperative fever. ROC curves analysis of the combination of these two factors on predicting postoperative fever showed AUC values were 0.731 (0.652-0.810). Moreover, a higher MAP score (OR 2.30) and longer operative time (OR 2.16) were significantly associated with higher hemoglobin drop on multivariate analysis.

CONCLUSION

A high MAP score was associated with postoperative fever and intraoperative hemorrhage in patients undergoing mPCNL. The MAP score can be a novel and easy predictive tool to help endourologists improve the awareness of mPCNL safety.

Comparison of perinephric fat measurements between malignant and benign renal tumours

Objective

To investigate different parameters derived from the quantity and quality of perinephric fat, and to compare their effectiveness in predicting the malignant pathology of renal tumours.

Methods

Data from patients diagnosed with renal tumour between April 2014 and December 2020 were retrospectively reviewed, and patients were categorized into malignant or benign tumour groups. Fat parameters, including perinephric fat volume (PFV), perinephric fat area (PFA), perinephric fat thickness (PFT), and Mayo adhesive probability (MAP) score were measured using abdominal computed tomography scans. Between-group differences were assessed by analysis of variance and χ²-test. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the performance of perinephric fat parameters in diagnosing malignancy.

Results

A total of 109 patients were included. MAP score, PFV, PFA, and PFT were significantly increased in the malignant versus benign tumour group, and after correction for body mass index (BMI), the indexed PFV/BMI, PFA/BMI, and PFT/BMI values remained significantly higher in the malignant tumour group. All parameters showed fair predictivity of malignancy, with comparable area under the curve values in the ROC curve.

Conclusion

An increased amount of perinephric fat is predictive of malignant pathology for renal tumours. The predictive accuracy for each perinephric fat parameter remained fair after correcting for BMI.

Fat Attenuation Index of Renal Cell Carcinoma Reveals Biological Characteristics and Survival Outcome

Purpose

The computed tomography fat attenuation index (FAI) is an ideal quantifiable imaging factor to identify the inflammation degree of peri-tumor adipose tissue. We aimed to verify whether FAI could reflect peri-tumor adipose inflammation, predict the survival outcome of renal cell carcinoma (RCC), and discover transcriptomic features of tumor tissues and adjacent adipocytes.

Materials and Methods

Two clinical cohorts (Fudan University Shanghai Cancer Center [FUSCC] cohort [n=129] and TCGA cohort [n=218]) were used to explore the association between FAI and clinical outcome. A prospective cohort (n = 19) was used to discover the molecular phenotyping of peri-tumor adipose tissue and tumor tissue according to their FAI value. A clinical cohort (n = 32) in which patients received cyto-reductive surgery was used to reveal the dynamic change of FAI.

Results

A high peri-tumor FAI was significantly associated with a worse outcome in both the FUSCC (HR = 2.28, p = 0.01) and the TCGA cohort (HR = 2.24, p <0.001). The analysis of the RNA expression of paired RCC tissue and peri-tumor fat tissue showed synchronized alterations in pathways such as cytokine-cytokine receptor interaction and complement and coagulation cascades. RCC tissues showed significant alterations in the neuroactive ligand-receptor interaction pathway. Immune deconvolution analysis showed enhanced infiltration of macrophages in high FAI tumor tissues with a lower angiogenesis level. We also observed synchronous dynamic changes in FAI and tumor size after targeted therapy.

Conclusion

In summary, FAI could be used in RCC to reflect the biological characteristics and tumor immune micro-environment of both the tumor and the peri-tumor adipose. High peri-tumor FAI had the potential to predict a worse survival outcome in various cohorts. This study demonstrates that the crosstalk exists between a tumor and its micro-environment and could be reflected easily by imaging procedures, which could facilitate clinical decision making.

Analysis of Clinical Characteristics, Radiological Predictors, Pathological Features, and Perioperative Outcomes Associated with Perinephric Fat Adhesion Degree

Background

To assess the clinical characteristics, radiological predictors, and pathological features of perinephric fat adhesion degree (PFAD) graded based on fixed criteria and to determine the impact of adherent perinephric fat (APF) on retroperitoneal laparoscopic partial nephrectomy (RLPN) outcomes.

Methods

84 patients undergoing RLPN were included and graded into 4 groups based on PFAD. Univariate and multivariate analyses were performed for clinical characteristics and radiological predictors of PFAD. Perioperative data were compared between APF groups and non-APF groups. Masson staining determined collagen fibers. Immunohistochemistry detected CD45 immune cells and CD34 vessels.

Results

20, 28, 18, and 18 patients were graded as normal perinephric fat (NPF), mild adherent perinephric fat (MiPF), moderate adherent perinephric fat (MoPF), and severe adherent perinephric fat (SPF), respectively. Multivariate analysis revealed that gender (p < 0.001), age (p = 0.003), and hypertension (p = 0.006) were significant clinical risk factors of PFAD, while radiological predictors included perinephric stranding (p = 0.001), posterior perinephric fat thickness (p = 0.009), and perinephric fat density (p = 0.02). APF was associated with drain output (p = 0.012) and accompanied by immune cells gathering in renal cortex near thickened renal capsule with many vessels.

Conclusions

Clinical characteristics and radiological predictors can evaluate PFAD and may assist to guide preoperative surgical option. Pathological features of APF reflect decapsulation and bleeding during kidney mobilization at RLPN.

Analysis of predictors of adherent perinephric fat and its impact on perioperative outcomes in laparoscopic partial nephrectomy: a retrospective case-control study

BACKGROUND

Adherent perinephric fat (APF), characterized by inflammatory fat surrounding the kidney, can limit the isolation of renal tumors and increase the operative difficulty in laparoscopic partial nephrectomy (LPN). The aim of this study was to investigate the predictors of APF and its impact on perioperative outcomes during LPN.

METHODS

A total of 215 consecutive patients undergoing LPN for renal cell carcinoma (RCC) from January 2017 to June 2019 at our institute were included. We divided these patients into two groups according to the presence of APF. Radiographic data were retrospectively collected from preoperative cross-sectional imaging. The perioperative clinical parameters were compared between the two groups. Univariate and multivariate analyses were performed to evaluate the predictive factors of APF.

RESULTS

APF was identified in 41 patients (19.1%) at the time of LPN. Univariate analysis demonstrated that APF was significantly correlated with the male gender (P = 0.001), higher body mass index (P = 0.002), lower preoperative estimated glomerular filtration rate (P = 0.004), greater posterior perinephric fat thickness (P < 0.001), greater perinephric stranding (P < 0.001), and higher Mayo Adhesive Probability (MAP) score (P < 0.001). The MAP score (P < 0.001) was the only variable that remained an independent predictor for APF in multivariate analysis. We found that patients with APF had longer operative times (P < 0.001), warm ischemia times (P = 0.001), and greater estimated blood loss (P = 0.003) than those without APF. However, there were no significant differences in surgical approach, transfusion rate, length of postoperative stay, complication rate, or surgical margin between the two groups.

CONCLUSIONS

Several specific clinical and radiographic factors including the MAP score can predict APF. The presence of APF is associated with an increased operative time, warm ischemia time, and greater estimated blood loss but has no impact on other perioperative outcomes in LPN.

Usefulness of the mayo adhesive probability score as a predictive factor for renal function deterioration after partial nephrectomy: a retrospective case-control study

PURPOSE

Whether the Mayo adhesive probability score, an index of the perinephric fat environment, could be a predictive factor for renal function deterioration after partial nephrectomy was investigated.

METHODS

A retrospective case-control study of 78 patients who underwent laparoscopic partial nephrectomy was performed. An estimated glomerular filtration rate preservation rate at ≤ 90% at 3 months after surgery was defined as postoperative renal function deterioration. These patients were divided into two groups (non-deterioration and deterioration groups). Patient factors including Mayo adhesive probability scores (both tumor and unaffected sides) and surgical factors were evaluated to identify the predictors for postoperative renal function deterioration. The statistical analysis used univariate and multivariate logistic regression analyses.

RESULTS

Thirty-seven (47.4%) patients had postoperative renal function deterioration after partial nephrectomy. Univariate analysis identified Mayo adhesive probability score on the unaffected side (p = 0.02), and warm ischemia time (p < 0.01) as predictors of postoperative renal function deterioration. On multivariate analyses, Mayo adhesive probability score on the unaffected side (odds ratio: 1.38 [1.05-1.79], p = 0.02) and warm ischemia time (odds ratio: 1.04 [1.01-1.07], p < 0.01) were significantly associated with postoperative renal function deterioration as same as univariate analysis. On receive operating characteristic curve analysis, Mayo adhesive probability score on the unaffected side (cutoff value 1.5; p = 0.02) and warm ischemia time (cutoff value 26.5 min; p = 0.01) were significant predictors of renal function deterioration 3 month after surgery.

CONCLUSION

The Mayo adhesive probability score on the unaffected side and warm ischemia time are useful predictors for renal function deterioration after partial nephrectomy.

TRIAL REGISTRATION NUMBER

2019-249, January 21st, 2019, retrospectively registered.

Open and Laparoscopic Partial Nephrectomy: Comparison and Validation of Preoperative Scoring Systems, Including PADUA, RENAL, ABC Nephrometric Scores and Perinephric Fat Evaluation with Mayo Adhesive Probability Score

Purpose

To evaluate potential associations between 4 nephrometric scoring systems, namely the PADUA (preoperative aspects and dimensions used for anatomical classification), RENAL (radius endophytic/exophytic nearness anterior posterior location), ABC (arterial-based complexity), and MAP (Mayo adhesive probability) scores and their individual components, with surgical and oncological outcomes of patients undergoing a partial nephrectomy.

Materials and Methods

A consecutive, monocentric cohort of partial nephrectomy patients was retrospectively analyzed. PADUA, RENAL, ABC and MAP nephrometry scores were determined from preoperative axial images. Unadjusted and adjusted associations between overall scores, individual components, surgical approach, complications and oncological outcomes were determined using univariate and multivariate logistic regressions.

Results

A total of 189 partial nephrectomies were performed in 181 patients, via an open or a laparoscopic approach. Among scoring systems, only the MAP classification, which assesses adherent perinephric fat, was associated with severe surgical complications as well as with operative time (p<0.05). Among all components of the PADUA and RENAL scores, only proximity of the tumor to the collecting system was associated with overall surgical complication rates, while the diameter of the tumor influenced the operative time (p<0.05). The ABC score was not relevant. Male gender, antiplatelet therapy, and a laparoscopic approach were associated with higher overall surgical complication rates (p<0.05). The number of oncologic recurrences during follow-up was too low to run statistical analyses.

Conclusion

Nephrometry scores could be simplified to predict surgical complications after partial nephrectomy. In this framework, adherent perinephric fat seemed to be strongly associated with an increased risk of surgical complications.

Impact of the Mayo Adhesive Probability Score on Donor and Recipient Outcomes After Living-donor Kidney Transplantation: A Retrospective, Single-center Study of 782 Transplants

Supplemental Digital Content is available in the text.

Background.

This study was performed to assess the impact of the Mayo Adhesive Probability (MAP) score on donor and recipient outcomes after living-donor kidney transplantation (LDKT).

Methods.

We retrospectively analyzed 782 transplants involving LDKT between February 2008 and October 2019 to assess the correlation between the MAP score and outcome after LDKT. We divided the transplants into 2 groups according to the donor MAP score: 0 (MAP₀) and 1–5 (MAP_1–5).

Results.

Compared with the MAP₀ group, donors in the MAP_1–5 group were significantly older, had higher body mass index, and were more likely to be men. The prevalences of hypertension, hyperlipidemia, and diabetes were also higher among donors in the MAP_1–5 group than among donors in the MAP₀ group. Operative time, estimated blood loss during donor nephrectomy, and percentage of glomerular sclerosis were significantly greater in the MAP_1–5 group than in the MAP₀ group. Donor and recipient perioperative complications were comparable between the 2 groups; death-censored graft survival rates also did not significantly differ between groups. Although the recipient mean estimated glomerular filtration rate (eGFR) from postoperative d 1 to 7 was significantly higher in the MAP₀ group than in the MAP_1–5 group (P = 0.007), eGFR reductions within 5 y after transplantation were similar between groups. There were no significant differences between groups in recipient mortality and biopsy-proven acute rejection episodes within 1 y after transplantation. Additionally, multivariate analysis showed that the only factors affecting recipient eGFR at postoperative d 7 were donor age, recipient age, and female sex (P < 0.001, <0.001, and =0.004, respectively).

Conclusions.

The MAP score did not influence surgical complications or graft survival; therefore, it should not affect donor selection.

Assessment of Patient-Related Operative Complexity During Partial Nephrectomy: Comparison of Two Tailored Methods for Measurement of Posterior Perinephric Fat Thickness on Preoperative CT

Background: Adherent perinephric fat affects operative complexity during partial nephrectomy (PN) and it could be predicted using computed tomography (CT) based on the Mayo adhesive probability (MAP) score. Objectives: To investigate reproducible measurement methods of perinephric fat with comparison of two tailored methods for measurement of posterior perinephric fat thickness (PPFT) on preoperative CT and examine the association between the methods and operative complexity in PN. Patients and Methods: This cross-sectional study included 72 consecutive patients who underwent robotic-assisted or open PN. The data on operative time, ischemia time, and pathologic results were obtained. Two radiologists independently assessed PPFT based on the MAP system in the first session, and subsequently by using two tailored methods in the second session and scored for perinephric fat stranding. The nephrometry scoring system was used for stratifying the complexity of renal masses. Multiple linear regression was used to evaluate the determinants of operative time and ischemia time. Results: For measurement of PPFT, intraclass correlation coefficients between the reviewers using two detailed methods showed no statistical difference (P = 0.173) but were significantly higher than the coefficients scored in the first session (P < 0.001). Nephrometry score was a determinant of ischemia time (P < 0.001 and 0.001 for two reviewers) and PPFT was identified as a determinant of operative time (P ≤ 0.023 in all the analysis using two different methods for both the reviewers) in robotic-assisted PN. Nephrometry score was identified as a determinant of ischemia time in open PN as per one of the reviewers (P = 0.006). Conclusion: The tailored methods presented herein were more reproducible than the MAP score and demonstrated that increased PPFT was related to longer operative time in robotic-assisted, and not in open PN.

Mayo Adhesive Probability (MAP) score of non-donated kidney aids in predicting post-operative renal function following donor nephrectomy

Background

To examine the association of preoperative Mayo Adhesive Probability (MAP) scores in the donor (MAP_d) and non-donor kidneys (MAP_nd) with post-donation renal function.

Methods

Three hundred thirty-one patients undergoing hand assisted laparoscopic donor nephrectomy (HALDN) were reviewed. MAP_d and MAP_nd were obtained. Estimated glomerular filtration rate (eGFR) was recorded preoperatively and at 1 day, 1 month, and 6 months postoperatively.

Results

Two hundred females and 131 males were evaluated with median BMI 26.4 kg/m² (range 17.1–39.6) and median age 45 years (range 19–78). MAP_d score was 0 for 231 patients (69.8%) and > 0 for 100 patients (30.2%). MAP_nd score was 0 for 234 patients (70.7%) and > 0 for 97 patients (29.3%). The median preoperative eGFR was 86.6 ml/min/1.73m² (range 48.8–138.4). After adjusting for preoperative eGFR, BMI, ASA score, and kidney sidedness, postoperative eGFR was associated with MAP score in the non-donated kidney (p = 0.014) but not in the donated kidney (p = 0.24). Compared to donors with MAP_nd = 0, donors with a MAP_nd > 0, mean eGFR was − 2.33 ml/min/1.73m² lower at postoperative day 1 (95% CI − 4.24 to − 0.41, p = 0.018), − 3.02 ml/min/1.73m² lower at 1 month (95% CI − 5.11 to − 0.93, p = 0.005), and − 2.63 ml/min/1.73m² lower at 6 months postoperatively (95% CI − 5.01 to − 0.26, p = 0.030).

Conclusions

MAP score > 0 in the non-donated kidney is associated with worse renal function in the 6 months following HALDN.

Perioperative Outcomes of Laparoscopic Radical Nephrectomy for Renal Mass in Patients on Dialysis or with Renal Transplant in Place Compared to Normal Controls

Background: The risk of renal cell carcinoma (RCC) development in the native kidney of patients on dialysis or with a renal transplant is increased compared to the general population. This study examines perioperative outcomes of laparoscopic radical nephrectomy (LN) in dialysis patients or renal transplant patients compared to normal controls. Methods: Four hundred twelve consecutive LN were evaluated (July 2007 to October 2018). Patients were divided into three groups (control, dialysis, and transplant). Perioperative outcomes, including operating room time (OT), postoperative complications, hospital length of stay, and 90-day readmission rates, were evaluated for the three groups. Results: There were 62 patients in the dialysis group, 20 renal transplants, and 330 normal controls. Dialysis patients were younger (median: 58 years versus 67 years; P = .002) and predominantly male (73% versus 59%, P = .047). Dialysis patients compared to controls had shorter total OT (median: 133 versus 149; P = .022), more papillary RCC (27% versus 10%; P < .001), and fewer high grade tumors (73% [8/11] versus 94% [100/106]; P = .038). Renal transplant patients had a higher rate of 90-day readmission (20% versus 6%; P = .034) and more papillary RCC (30% versus 10%; P = .016) compared to controls. Conclusion: LN on dialysis patients does not alter expected perioperative outcomes compared to a large cohort of control LN. LN on renal transplant patients carries a higher 90-day readmission rate than control LN.

Predictive Value of Nephrometry Scores in Nephron-sparing Surgery: A Systematic Review and Meta-analysis

CONTEXT

Over the last decade, several nephrometry scores (NSs) have been introduced with the aim of facilitating preoperative decision making, planning, and counseling in the field of nephron-sparing surgery. However, their predictive role remains controversial.

OBJECTIVE

To describe currently available nephrometry scores and to determine their predictive role for different outcomes by performing a systematic review and meta-analysis of the literature.

EVIDENCE ACQUISITION

PubMed, Embase®, and Web of Science were screened to identify eligible studies. Identification and selection of the reports were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). A pooled analysis of NS predictive role of intraoperative, postoperative, oncological, and functional outcomes was performed. Odds ratio was considered the effect size. All the analyses were performed using Stata 15.0, and statistical significance was set at p≤ 0.05.

EVIDENCE SYNTHESIS

Overall, 51 studies meeting our inclusion criteria were identified and considered for the analysis. Except for one prospective randomized trial, all the studies were retrospective. All the studies were found to be of intermediate quality, except for one of high quality. Most studies assessed the predictive role of the Radius-Exophytic/Endophytic-Nearness-Anterior/Posterior-Location (RENAL) and Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) scores, mostly regarding complications after nephron-sparing surgery. RENAL was an independent predictor of an on-clamp procedure (p< 0.001). Mayo Adhesive Probability score was related to adhesive perinephric fat (p= 0.005). Continuous and high-complexity RENAL scores were predictors of warm ischemia time (WIT; p= 0.006 and p< 0.001, respectively). Continuous (p< 0.001) and high-complexity (p< 0.001) PADUA scores were related to WIT. Continuous and high-complexity RENAL scores were predictors of overall complications (p= 0.002 and p< 0.001, respectively). PADUA score was related to complications both as continuous (p< 0.001) and as a categorical value (p< 0.002). The RENAL scores R=3 (p= 0.008), E=2 (p= 0.039), and hilar location (p= 0.006) were predictors of histological malignancy. Continuous and categorical RENAL scores were independent predictors of an estimated glomerular filtration rate (eGFR) increase (p= 0.006 and p< 0.001, respectively). The Diameter-Axial-Polar score (p= 0.018) and Peritumoral Artery Scoring System (PASS; p= 0.02) were also independent predictors.

CONCLUSIONS

The literature regarding nephrometry scoring systems is sparse, and mostly focused on RENAL and PADUA, which are easy to calculate and have a good correlation with most outcomes. Renal Pelvic Score is the best predictor of pelvicalyceal entry/repair and urine leak, whereas Surgical Approach Renal Ranking and PASS strongly predict surgical approach and renal function variation, respectively. Other nephrometry scores based on mathematical models are limited by their complexity, and they lack evidence supporting their predictive value.

PATIENT SUMMARY

We reviewed the medical literature regarding the use and value of so-called "nephrometry scores," which are scoring systems based on radiological imaging and made to grade the complexity of a renal tumor. We analyzed whether these scoring systems can predict some of the outcomes of patients undergoing surgical removal of renal tumors.

BioScore (B7-H1, survivin, and Ki-67) does not predict cancer-specific mortality in surgically treated patients with renal cell carcinoma: An external validation study

BACKGROUND

To externally validate' BioScore', a biomarker-based scoring system using immunohistochemical tumor expression levels of B7-H1, survivin, and Ki-67, in a single-center cohort of renal cell carcinoma (RCC) patients. Additionally, we investigated the potential benefit of BioScore as compared to the Mayo Clinic stage, size, grade, and necrosis (SSIGN) score.

MATERIALS AND METHODS

The validation cohort comprised 393 nonmetastatic RCC patients treated with radical nephrectomy or nephron-sparing surgery from 1999 to 2004. Kaplan-Meier estimators, the log-rank test, uni- and multivariable Cox regression models, and measures of discrimination were used to quantify the prognostic performance of BioScore regarding cancer-specific mortality (CSM).

RESULTS

During a median follow-up of 7.8 years, 69/132 (52%) deaths were adjudicated to progressive disease. BioScore was weakly associated with CSM in univariable analysis (hazard ratio per 1 point increase = 1.12, 95% confidence interval = 1.02-1.23, P = 0.023). However, this association did not prevail after adjusting for other adverse prognostic factors as represented by the SSIGN score. The discriminative performance of BioScore was very modest (Harrell's C-Index = 0.60) and did not improve the SSIGN score (P = 0.341), which already showed an excellent discrimination, as evidenced by Harrell's C-Index of 0.81. In a sensitivity analysis regarding clear cell RCC patients only, B7-H1 positivity did not emerge as a statistically significant predictor of CSM.

CONCLUSION

Although a higher BioScore was significantly associated with a higher CSM, the magnitude of this association was weak and not independent from other prognosticators. Moreover, BioScore did not improve the prognostic accuracy of the SSIGN score.

A comparison of perinephric fat surface area and Mayo Adhesive Probability score in predicting malignancy in T1 renal masses

INTRODUCTION

Recent studies have proposed that nearby fat deposits may have metabolic influence on kidney cancer pathobiology. Both fat quantity and quality may play unique roles in this complex relationship. As such, we investigated whether perinephric fat surface area (PFA), a quantitative measure of fat, or Mayo Adhesive Probability (MAP) score, a qualitative measure, were predictive of malignant pathology or Fuhrman grade in small renal masses.

METHODS

A total of 317 patients undergoing minimally invasive partial nephrectomy between 2010 and 2016 for renal masses were retrospectively reviewed. Preoperative abdominal CT and MRI scans were measured for PFA and MAP scores. Multiple binary logistic regression models were created to identify predictive factors of malignant disease and Fuhrman grade.

RESULTS

A total of 253 patients had malignant masses, while 64 had benign masses. A total of 189 of the malignant masses were T1a, while 64 were designated T1b. A total of 221 patients with malignant masses had reported Fuhrman grades. Of these 211 patients, 143 (64.7%) had low-grade and 78 (35.3%) had high-grade disease. Mean PFA was 18.0 ± 13.3 cm², while mean MAP score was 2.6 ± 1.2. Binary logistic regression analysis yielded three variables in the best-fit model for predictors of malignant pathology: MAP score (OR = 1.374, 95% CI: 1.007-1.873, P = 0.045), male sex (OR = 2.058, 95% CI: 1.004-4.218, P = 0.049), and BMI (OR = 1.064, 95% CI: 0.998-1.135, P = 0.059). Neither MAP nor PFA was predictive of Fuhrman grade.

CONCLUSIONS

MAP score, a measure of perinephric fat quality, but not PFA, a qualitative measure of fat quantity, was predictive of malignant pathology, raising the question whether fat quality rather than quantity may be involved in the pathophysiology of RCC in a large and diverse patient population. Understanding the increasing burden of obesity, further studies are needed to elaborate on these findings and to discern the exact relationship between perinephric fat deposits and renal tumorigenesis.

[Retrospective comparison of the reproducibility and the performances of R.E.N.A.L. score, 12 segments score and UPRCC score for the partial nephrectomy]

INTRODUCTION

Compare three morphometrics scores of the kidney on the reproductibility and the predictability of complications per- and post-partial nephrectomy.

MATERIALS AND METHODS

This comparative study analyzed a monocentric retrospective cohort of 47 patients affected by a unique renal tumor and operated by partial nephrectomy by lumbotomy excluding the genetic diseases from January till December, 2014. The preoperative scanners were reviewed in double-blind by a radiologist and an internal surgeon who classified each tumor according to the three classifications: R.E.N.A.L. score, score in 12 segments and the University Paris Renal Cancer Classification (UPRCC). The judging criteria were the operative and ischemic duration, the blood loss, the preoperative injuries, the length of the hospital stay, the postoperative complications according to the Clavien-Dindo classification. The Cohen's kappa coefficient and the one-way analysis of variance were used respectively to compare the inter-observer reproducibility and the predictability of the complications for each classification.

RESULTS

Forty-four tumors of which 30 (64%) were on the left kidney, with an average size of 55.19mm with 17 (39%) on the upper pole, 12 (27%) on the lower pole and 15 (34%) medio-renal. The UPRCC was the most reproductible classification with 90% inter-observer concordance against 84% for the R.E.N.A.L. score and 72% for the score in 12 segments. The most predictable classification of complications was the score in 12 segments in particular thanks to the subgroup including the number of segments reached which allows to predict significantly the risk of a duration of intervention, prolonged ischemia and the risk of blood loss (P=0.03, 0.06 and <0.001).

CONCLUSION

The main result of this study is that, as in the majority of the previous studies on morphometrics scores, no score allows to predict the postoperative complications.

LEVEL OF EVIDENCE

4.

Risk Assessment in Small Renal Masses: A Review Article

The incidence of localized renal cell carcinoma (RCC) has been steadily increasing, in large part because of the increased use of imaging. Optimizing the management of localized RCC has become one of the leading priorities and foremost challenges within the urologic-oncologic community. Adequate risk stratification of patients following the diagnosis of localized RCC has become meaningful in deciding whether to treat, how to treat, and how intensively to treat. This article characterizes the existing risk assessment models that can be useful as treatment decision aids for patients with localized RCC.

Renal Tumor Anatomic Complexity: Clinical Implications for Urologists

Anatomic tumor complexity can be objectively measured and reported using nephrometry. Various scoring systems have been developed in an attempt to correlate tumor complexity with intraoperative and postoperative outcomes. Nephrometry may also predict tumor biology in a noninvasive, reproducible manner. Other scoring systems can help predict surgical complexity and the likelihood of complications, independent of tumor characteristics. The accumulated data in this new field provide provocative evidence that objectifying anatomic complexity can consolidate reporting mechanisms and improve metrics of comparisons. Further prospective validation is needed to understand the full descriptive and predictive ability of the various nephrometry scores.

Mayo Adhesive Probability Score Is an Independent Computed Tomography Scan Predictor of Adherent Perinephric Fat in Open Partial Nephrectomy

OBJECTIVE

To evaluate predictive radiological elements for adherent perinephric fat (APF) and the Mayo adhesive probability (MAP) score in the setting of open partial nephrectomy, and to assess their reproducibility.

PATIENTS AND METHODS

We performed a retrospective case-control study involving 86 patients who had open partial nephrectomies performed by a single surgeon between January 1, 2009 and April 1, 2015. Radiological elements were assessed by 4 readers blinded to patient APF status. Univariate and multivariate analyses were performed for all radiological and clinical factors. Reproducibility was analyzed using agreement coefficients.

RESULTS

On univariate analysis for radiological findings, lateral and posterior fat thickness (odds ratio [OR]: 1.084 [1.033, 1.138], P < .001), stranding (OR: 2.179 [1.431, 3.318], P < .001), -80 HU fat area, and the MAP score (OR: 1.797 [1.332, 2.424], P < .001) were predictive of APF. On multivariate analysis, only age and the MAP score remained statistically significant (OR: 1.060 [1.005, 1.118], P = .03; and OR: 1.560 [1.137, 2.139], P = .0058, respectively). The reproducibility of the MAP score was fair (AC1 = 0.367 and kappa F = 0.353), as was that of stranding (AC1 = 0.499, kappa F = 0.376). The agreement was important if we defined a "low" (0 to 3) or "high" (4 or 5) score (AC1 = 0.706 and kappa F = 0.681).

CONCLUSION

The MAP score was the element that best predicted APF in our study, although its reproducibility among our readers was only fair. The agreement becomes important if we defined "low or high" score.

Prospective assessment and histological analysis of adherent perinephric fat in partial nephrectomies

OBJECTIVES

The complexity of partial nephrectomy (PN) is partly anticipated by morphometric tumor-based scores that do not consider patient-related issues such as adherent perinephric fat (APF). Also, the objective is to prospectively assess the predictive factors of APF during PN, its effect on complications, and to correlate it to the histological reality.

METHODS

A total of 125 consecutive patients undergoing robotic or open PN were prospectively included. The Mayo adhesive probability score (MAP score) was compared to the peroperative presence of APF defined by a score≥2. Adipose tissue was analyzed histologically for fibrosis and inflammatory infiltrate of CD68+macrophages. Univariate and multivariate logistic regression analyses were performed to evaluate predictive factors of APF, and outcomes were compared using chi-square and Kruskal-Wallis tests.

RESULTS

APF was present in 51 patients (40.8%) and associated with slight longer operating time and increased blood loss. Warm ischemia time, margins, transfusion, and the Clavien-Dindo score were not different. In multivariate analysis, only male sex, age, waist circumference, fat density on computed tomography, and MAP score were significant predictors of APF. A radioclinical score was more predictive of APF than MAP score alone. Histologically, there was no macrophage infiltration but larger adipocytes in APF without significant differences in fibrosis.

CONCLUSIONS

APF can be accurately predicted using radioclinical data as the MAP score, combined with sex, age, and waist circumference. APF is associated with increased operative time and blood loss without postoperative complications. Histological analysis finds larger adipocytes in APF without inflammatory infiltrate, and no difference in fibrosis.

Synthetic Renal Capsule Tailoring: A Novel Renorrhaphy Technique After Subcapsular Dissection of Renal Tumors with Severe Adherent Perirenal Fat During Laparoscopic Partial Nephrectomy

BACKGROUND

Multiple factors can account for surgical complexity during laparoscopic partial nephrectomy (LPN); severe adhesion of perirenal fat (PRF) is a crucial one. Consequent renal decapsulation can deem renorrhaphy a very challenging task. We propose a novel technique (synthetic renal capsule tailoring [SYRCT]) to facilitate renorrhaphy in decapsulated kidneys and suggest early decapsulation as a safe option in cases with severe PRF.

MATERIALS AND METHODS

We retrospectively analyzed perioperative results of this novel technique performed in cases with severe PRF. All cases were classified as high grade in the Mayo Adhesive Probability (MAP) score.

RESULTS

A total of six cases were performed with the SYRCT technique. All patients were male with a mean age of 70 years (62-76 years) and mean body mass index of 30 kg/m² (23.66-33.86). Of the six cases, five were T1a and 1 T1b. Mean tumor size was 2.83 cm (range 1.2-6 cm). Mean operative time was 121 minutes (range 74-150 minutes); mean warm ischemia time was 17.2 minutes (range 13-25 minutes). Mean operative bleeding was 128 mL (range 50-250 mL). Mean hospital stay was 2.3 days. There were no surgical complications greater or equal to Clavien II.

CONCLUSION

Performing complete renal decapsulation with subcapsular dissection and SYRCT in cases with high MAP score and severe PRF is safe and reproducible. Using this novel technique, we were able to obtain perioperative results comparable to the ones we found in LPN with normal PRF.