Predictive factors of renal function after robot-assisted partial nephrectomy in clinical T1b tumors

Robot-assisted partial nephrectomy (RAPN) has been shown to be a safe and effective method for treatment of small renal tumors, including clinical T1b renal cell carcinoma (RCC); however, the impact of RAPN for cT1b renal tumors on renal function is not well understood. In this retrospective study, 50 patients who underwent RAPN for cT1b renal tumors were evaluated for pre- and post-operative renal function and perioperative clinical factors. Renal function was assessed using the estimated glomerular filtration rate (eGFR) at baseline and on postoperative days (POD) 1, 7, 30, and 180.A significant renal functional decline was defined as ≥ 15% reduction in eGFR at POD180 compared with eGFR at baseline. Logistic regression analyses were used to identify risk factors for renal function decline, including age, sex, RENAL nephrometry score, operative time, and estimated blood loss. The median patient age was 62 years, and the median tumor diameter and RENAL nephrometry score were 44 mm (IQR 43-50) and 8 (IQR 7-9), respectively. Of these patients, 16 (36%) showed a significant renal functional decline at POD 180. In the multivariate analysis, the L component of the RENAL nephrometry score and an estimated blood loss of 200 mL or more were identified as significant risk factors for renal functional decline. These findings suggest that the preoperatively definable L component of the RENAL nephrometry score and intraoperative blood loss, which may be modifiable factors, play significant roles in post-RAPN renal function decline.

Impacts of Complete Endophytic Renal Tumors on Surgical, Functional, and Oncological Outcomes of Robot-Assisted Partial Nephrectomy

Objective: Complete endophytic renal tumors (CERTs) are the most challenging for robot-assisted partial nephrectomy (RAPN). This study aimed to determine the impact of CERT on outcomes of RAPN. Methods: All RAPN cases for localized renal tumor undertaken at Yokohama City University Hospital between 2016 and 2023 were enrolled. Tumor characteristics and surgical, functional, and oncologic outcomes of RAPN were compared between CERT and non-CERT groups. Results: Consecutive 666 patients were enrolled, and 76 (11.4%) were identified as CERT (3 points of "E" score). CERT showed smaller tumor diameters (p < 0.001), more predominant hilar tumor (p = 0.029), higher "N" scores (p < 0.001) and "L" scores (p = 0.006) than non-CERT. The CERT group showed longer warm ischemia times (p < 0.001), more frequent positive surgical margins (p = 0.028), and relatively lower trifecta achievement rates (p = 0.101) than the non-CERT group. In multivariable analysis, the CERT was an independent predictor for trifecta achievement but not for pentafecta achievement. Conclusions: CERT was associated with longer warm ischemia time, positive surgical margin, and lower trifecta achievement, but not with surgical complication and pentafecta achievement in RAPN. This study suggested that CERT had limited influence on long-term renal functional preservation; however, it had strong impacts on short-term surgical outcome.

Image-guided percutaneous cryoablation of T1b renal cell carcinomas in patients with comorbidities

PURPOSE

To investigate the influence of comorbidities and tumor characteristics on outcomes following percutaneous cryoablation (PCA) of T1b renal cell carcinoma (RCC).

MATERIALS AND METHODS

Age-adjusted Charlson comorbidity index (ACCI); standardized system for quantitating renal tumor size, location, and depth (RENAL nephrometry score [RNS]); and local tumor control and survival were retrospectively investigated in 28 patients who underwent PCA for stage T1b RCC. Risk factors for elevated serum creatinine levels were also investigated.

RESULTS

Complete ablation was obtained in 27 of 28 patients. Two cases of metastasis were observed; one patient died 12 months after PCA. Overall survival at 5 years was 79.1%, with a mean follow-up of 42.0 ± 16.0 months. Local tumor control was not correlated with the ACCI and RNS. Worsening renal function 3 months after PCA was observed in ten patients, and it correlated with the presence of single kidneys (7/28 patients; p = 0.023). Significant worsening of renal function continued until 1 year after PCA (p = 0.013). Having a single kidney was a risk factor for worsened renal function after PCA (odds ratio, 8.00; 95% confidence interval 1.170-54.724).

CONCLUSION

PCA for T1b RCC confers positive local tumor control regardless of comorbidities and tumor characteristics.

The effectiveness of RENAL nephrometry score in ablated renal tumors via radiofrequency ablation or cryoablation

Background/aim

This study aimed to evaluate the clinical efficacy of radiofrequency ablation (RFA) and cryotherapy and to scrutinize the therapeutic success of the RENAL (radius, exophytic/endophytic, nearness to collecting system, anterior/posterior, and location) nephrometry score in terms of possible complications and the predictive status of oncological results.

Materials and methods

Forty-five patients with biopsy-proven renal cell carcinomas (32 males, 13 females) treated with RFA and cryotherapy were included. Patients were 22–90 years old (average: 59.2 years). Statistical analyses were performed using SPSS for Windows.

Results

A total of 79 lesions with dimensions varying between 0.9 and 4.5 cm (average: 2.2 cm) were ablated. Complete ablation was achieved for 72 (91.1%) lesions. Six repeat RFA sessions were applied for 4 (5%) lesions with residue/recurrence. The average RENAL nephrometry scores of lesions that underwent complete ablation and those that developed residue/recurrence were 6.3 and 7.7, respectively. The average recurrence-free survival time was 34.8 months (range: 3–55 months), while it was 44.6 months (range: 6–55 months) for cryotherapy and 28.6 months (range: 3–50 months) for RFA.

Conclusion

Ablative therapies are minimally invasive and effective methods for treating small renal tumors. RENAL nephrometry scoring is a valuable system for standardizing renal tumors and evaluating the success of ablative therapies, possible complications, and oncological results.

RENAL nephrometry score: Predicting perioperative outcomes following open partial nephrectomy

Background

Partial nephrectomy has emerged as a standard treatment for small renal masses offering oncologic control equivalent to radical nephrectomy, with preservation of renal function and evidence for equivalent survival. In this study, we evaluated RENAL nephrometry score (RNS) in predicting perioperative outcomes in patients with partial nephrectomy.

Materials and Methods

This was a prospective observational study conducted from February 2016 to August 2017 which included patients who underwent partial nephrectomy. The patients were divided into three groups depending on the complexity scores (low, moderate, and high). Tumors were assigned RNS and tumor-node-metastasis staging of the clinically malignant tumors was done. Blood loss, warm ischemia time (WIT), and surgical complications were assessed.

Results

A total of 20 patients underwent open partial nephrectomy during the study. There were 4 (20%) low, 11 (55%) moderate, and 5 (25%) high-complexity lesions. Blood loss was significantly different in three groups. All the cases in high-complexity group were performed with clamping the renal vessels with a mean WIT of 29 min. The overall complication rates were significantly different between the groups (P = 0.007); however, majority of the complications were low grade (Grades I and II) and were managed conservatively.

Conclusion

In the present study, RNS was correlated with predicting surgical access route, need for clamping during partial nephrectomy, blood loss, decrease in glomerular filtration rate of operated kidneys, postoperative complications, and tumor grade.

Predicting trifecta outcomes after robot-assisted nephron-sparing surgery: Beyond the nephrometry score

Purpose

RENAL nephrometry score (RNS) was devised for deciding the approach for renal tumors. It is increasingly used in predicting perioperative outcomes with variable results. The actual difficulty encountered during surgery depends on a number of other variables. The main purpose of this prospective study was to identify these variables which are not addressed by current RNS.

Materials and Methods

Forty-nine patients undergoing robotic nephron sparing surgery from January 2015 onward were included. RNS was calculated from the imaging. Operating surgeon rated each surgery on a Likert scale of 0–4 after the completion of the procedure. The questionnaire was pre-validated in 5 cases before administration. The correlation between the surgeon rating and RNS with perioperative parameters and trifecta outcomes were calculated.

Results

Forty-seven percent surgeries were rated easy, and 53.0% were rated as difficult. Surgeries for hilar, posterior location and presence of supernumerary vessels were found to be the a cause of difficulty. Trifecta outcomes were achieved in 37/49 patients (75.5%). The mean rating was 2.580±0.900 in trifecta negative patients while it was 1.410±0.832 in trifecta positive patient (p<0.0001). Surgeon's rating correlated positively with trifecta outcomes (likelihood ratio=15.75, p=0.006).

Conclusions

The RNS remained a useful tool for determining renal tumor complexity. The intraoperative difficulty faced by the surgeon can be rated which can better predict perioperative trifecta outcomes. A useful predicting tool can be developed using the two parameters (RNS and surgeon rated difficulty).

Percutaneous Renal Biopsies for Small Renal Masses: Complex Tumors on Nephrometry Should Be the First Targets

OBJECTIVE

To assess the diagnostic yield, accuracy, and complications rate for computed tomography (CT)-guided renal biopsies for solid renal masses (SRM); to analyze predictive factors for diagnostic biopsies.

PATIENTS AND METHODS

We performed a single-center, retrospective study based on a pathologic database query for CT-guided, percutaneous renal biopsies. Inclusion criteria included presence of SRM; exclusion criteria included the presence of metastases, non-cT1a or higher cancer (> 4 cm), and non-CT-guided techniques. Of 119 patients who underwent renal biopsies, 40 (34%) were excluded from the study; 79 (66%) biopsy outcomes were analyzed. Clinical, radiologic (RENAL score), and pathologic features were reported. Differences between contributive and noncontributive biopsies were tested with Mann-Whitney U or chi-square tests, as appropriate. Multiple-variable analyses searching for predicting factors of biopsy contribution were performed with binary logistic regressions.

RESULTS

CT-guided renal biopsies for SRM present a high yield (88.6%) and high accuracy for differentiating malignant from benign tumors (96%). They are less accurate for histologic subtype (93%) and unreliable for Fuhrman grading (64%). CT-guided renal biopsy is safe (minor complication rate, 2.5%) and helped prevent unnecessary surgery in 30.4% of the cohort. Tumor complexity with high RENAL score was a predictive factor (P = .02) of contributive biopsy.

CONCLUSION

SRM biopsy is a safe, reliable procedure that can help determine the best treatment strategy for patients. It seems more beneficial for nephrometry complex tumors when surgical extirpation is more likely to be complicated. SRM biopsy might be encouraged in clinical practice for complex tumors.