R.E.N.A.L. (Radius, Exophytic/Endophytic, Nearness to Collecting System or Sinus, Anterior/Posterior, and Location Relative to Polar Lines) Nephrometry Score Predicts Early Tumor Recurrence and Complications after Percutaneous Ablative Therapies for Renal Cell Carcinoma: A 5-Year Experience

Utility of the RENAL index -Radius; Exophytic/endophytic; Nearness to sinus; Anterior/posterior; Location relative to polar lines- in the management of renal masses

CONTEXT

The growing incidence of renal masses and the wide range of available treatments require predictive tools that support the decision making process. The RENAL index -Radius; Exophytic/endophytic; Nearness to sinus; Anterior/posterior; Location relative to polar lines- helps standardise the anatomy of a renal mass by differentiating 3 groups of complexity. Since the introduction of the index, there have been a growing number of studies, some of which have been conflicting, that have evaluated the clinical utility of its implementation.

OBJECTIVE

To analyse the scientific evidence on the relationship between the RENAL index and the main strategies for managing renal masses.

ACQUISITION OF THE EVIDENCE

A search was conducted in the Medline database, which found 576 references on the RENAL index. In keeping with the PRISM Declaration, we selected 100 abstracts and ultimately reviewed 96 articles.

SYNTHESIS OF THE EVIDENCE

The RENAL index has a high degree of interobserver correlation and has been validated as a predictive nomogram of histological results. In active surveillance, the index has been related to the tumour growth rate and probability of nephrectomy. In ablative therapy, the index has been associated with therapeutic efficacy, complications and tumour recurrence. In partial nephrectomy, the index has been related to the rate of complications, conversion to radical surgery, ischaemia time, function preservation and tumour recurrence, a finding also observed in radical nephrectomy.

CONCLUSIONS

The RENAL index is an objective, reproducible and useful system as a predictive tool of highly relevant clinical parameters such as the rate of complications, ischaemia time, renal function and oncological results in the various currently accepted treatments for the management of renal masses.

Oncological outcomes and complication rates after laparoscopic-assisted cryoablation: a European Registry for Renal Cryoablation (EuRECA) multi-institutional study

OBJECTIVE

To assess complication rates and intermediate oncological outcomes of laparoscopic-assisted cryoablation (LCA) in patients with small renal masses (SRMs).

PATIENTS AND METHODS

A retrospective review of 808 patients treated with LCA for T1a SRMs from 2005 to 2015 at eight European institutions. Complications were analysed according to the Clavien-Dindo classification. Kaplan-Meier analyses were used to estimate 5- and 10-year disease-free survival (DFS) and overall survival (OS).

RESULTS

The median [interquartile (IQR)] age was 67 (58-74) years. The median (IQR) tumour size was 25 (19-30) mm. The transperitoneal approach was used in 77.7% of the patients. The median postoperative hospital stay was 2 days. In all, 514 patients with a biopsy-confirmed renal cell carcinoma (RCC) were available for survival analyses. The median (IQR) follow-up for the RCC-cohort was 36 (14-56) months. A total of 32 patients (6.2%) were diagnosed with treatment failure. The 5-/10-year DFS was 90.4%/80.0% and 5-/10-year OS was 83.2%/64.4%, respectively. A total of 134 postoperative complications (16.6%) were reported, with severe complications (grade ≥III) in 26 patients (3.2%). An American Society of Anesthesiologists score of 3 was associated with an increased risk of overall complications (odds ratio 2.85, 95% confidence interval 1.32-6.20; P = 0.005).

CONCLUSIONS

This large series of LCA demonstrates satisfactory long-term oncological outcomes for SRMs. However, although LCA is considered a minimally invasive procedure, risk of complications should be considered when counselling patients.

Percutaneous microwave ablation of T1a and T1b renal cell carcinoma: short-term efficacy and complications with emphasis on tumor complexity and single session treatment

PURPOSE

To update the oncologic outcomes and safety for microwave (MW) ablation of T1a (≤4.0 cm) and T1b (4.1-7.0 cm) renal cell carcinoma (RCC) with emphasis on tumor complexity and single session treatment.

MATERIALS AND METHODS

Retrospective review of 29 consecutive patients (30 tumors) with localized (NOMO) RCC (23 T1a; 7 T1b) treated with percutaneous MW ablation between 3/2013 and 6/2014. Primary outcomes investigated were technical success, local tumor progression (LTP), and complications. Technical success was assessed with contrast-enhanced computed tomography (CECT) immediately after MW ablation. Presence of LTP was assessed with CECT or contrast-enhanced magnetic resonance at 6-month target intervals for the first two years and annually thereafter. Complications were categorized using the Clavien-Dindo classification system.

RESULTS

Median tumor diameter was 2.8 cm [IQR 2.1-3.3] for T1a and 4.7 cm [IQR 4.1-5.7] for T1b tumors. Median RENAL nephrometry score was 7 [IQR 4-8] for T1a tumors and 9 [IQR 6.25-9.75] for T1b tumors. Technical success was achieved for 22 T1a (96%) and 7 T1b (100%) tumors. There were no LTP during a median imaging follow-up of 12.0 months [IQR 6-18] for the 23 patients (24 tumors) with greater than 6 months of follow-up. There were three Clavien-Dindo grade I-II complication (10%) and no Clavien-Dindo grade III-V complications (0%). All but two patients (93%) are alive without metastatic disease; two patients died after 12-month follow-up of causes unrelated to the MW ablation.

CONCLUSION

Percutaneous MW ablation appears to be a safe and effective treatment option for low, moderate, and highly complex T1a and T1b RCC in early follow-up.

R.E.N.A.L. Score Outperforms PADUA Score, C-Index and DAP Score for Outcome Prediction of Nephron Sparing Surgery in a Selected Cohort

PURPOSE

Several nephrometry scores have been proposed to predict perioperative outcomes in renal surgery. We evaluated which nephrometry score correlates best with the MIC (margin, ischemia and complications) score and quantitative perioperative outcomes in nephron sparing surgery.

MATERIALS AND METHODS

Data on 188 patients undergoing nephron sparing surgery were retrospectively investigated for patient, operative and tumor characteristics. Nephrometry scores, including R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, hilar tumor touching the main renal artery or vein and location relative to polar lines), PADUA (preoperative aspects and dimensions used for an anatomical), C-index (concordance index) and DAP (diameter-axial-polar), were measured on preoperative computerized tomography or magnetic resonance imaging and coded continuously and categorically. Parameters pertaining to tumor margin, ischemia and complications were recorded as binary scores and classified as MIC achievement. Operative time, estimated blood loss, warm ischemia time and hospital stay were recorded as quantitative perioperative outcomes.

RESULTS

The R.E.N.A.L. score correlated best with MIC and quantitative perioperative outcomes. The continuously coded R.E.N.A.L. score was predictive of MIC on univariate analysis (OR 0.75, 95% CI 0.58-0.97, p = 0.03) and it had the best predictive value on multivariate logistic regression analysis (OR 0.31, 95% CI 0.18-0.82, p = 0.03). The C-index but not the PADUA or the DAP score was predictive of MIC on univariate and multivariate logistic regression analysis. MIC achievement rates were significantly higher for low than for high complexity tumors as assessed by categorically coded R.E.N.A.L. score, C-index and DAP scores. Continuously coded R.E.N.A.L. and PADUA scores positively correlated with operative time, warm ischemia time and hospital stay. The C-index and the DAP score correlated with warm ischemia time.

CONCLUSIONS

Of 4 nephrometry scores the R.E.N.A.L. score correlated best with MIC achievement and quantitative perioperative outcomes of nephron sparing surgery.

Kidney cancer focal cryoablation trend: does location or approach matter?

PURPOSE

We evaluated the current indications and surgical and survival outcomes for cryoablation (CA) using either a percutaneous (PCA) or a laparoscopic approach (LCA). We also investigated the ability of the PADUA score to predict the risk of complications and local recurrence.

METHODS

A retrospective analysis was performed at two European tertiary referral centers. Parameters analyzed included size, location, approach, operative time, hospital stay, complications, and functional and oncologic outcomes. Univariate and multivariate analyses were performed. An ROC analysis was conducted to evaluate the accuracy of the PADUA score.

RESULTS

Eighty patients were included. Mean tumor size was 2.6 cm. PCA was more often performed in posterior (95 vs. 60 %), inferior (72 vs. 32 %), and lateral (87 vs. 55 %) tumors. The global complication rate was 8.75 %, although proximity to the renal sinus resulted in a higher rate (30 vs. 4 %). Mean follow-up was 34 and 23 months for LCA and PCA, respectively. The 5-year recurrence-free survival was 76 and 90 % for LCA and PCA, respectively. Multivariate analysis showed that tumor involvement of the collecting system was predictive of recurrence. Under ROC analysis, PADUA score was a mild predictor for complications (AUC = 0.601) and a good predictor for recurrence (AUC = 0.723); PADUA ≥8 was identified as a cutoff for patients to a higher risk of recurrence.

CONCLUSIONS

The percutaneous approach is confirmed to be the preferred CA technique for posterior and lateral tumors. CA in deeper renal lesions and tumors with PADUA score ≥8 might entail a higher risk of recurrence, and closer follow-up should be considered in these patients.