Peri-operative and local control outcomes of robot-assisted partial nephrectomy vs percutaneous cryoablation for renal masses: comparison after matching on radiological stage and renal score.

OBJECTIVES: To compare the oncological outcomes of percutaneous cryoablation (PCA) vs robot-assisted partial nephrectomy (RAPN) for the treatment of T1 renal tumours. PATIENTS AND METHODS: We conducted a retrospective study in all patients treated by RAPN or PCA for malignant renal tumours in one of four centres between 2009 and 2016. Tumours were paired one by one using radiological tumour stage and RENAL nephrometry score (package matchit, R software version 3.2.2). Malignancy was confirmed by biopsy for all patients in the PCA group. Patient characteristics before and after matching and oncological results were compared between the two groups. Cox regression, adjusted for age, treatment type, histological type and margins, was used to identify factors associated with time to local recurrence. Positive margins were defined histologically in the RAPN group and radiologically in the PCA group. RESULTS: A total of 647 patients were identified; 470 underwent RAPN and 177 underwent PCA. After matching, there was no significant difference between the two groups (RAPN, n = 177; PCA, n = 177) with regard to tumour stage, RENAL nephrometry score, tumour size (27.6 vs 25.9 mm; P = 0.07) and gender ratio. Patients in the PCA group remained significantly older (69.9 vs 59.8 years; P < 0.001). The absolute recurrence rate was 2.8% in the RAPN group vs 8.4% in the PCA group (P = 0.03). The 5-year recurrence-free survival rate was 85% in the PCA group vs 95% in the RAPN group (log-rank P = 0.02). In multivariate analysis, the presence of positive margins and the type of treatment were the two factors significantly associated with local recurrence (P < 0.001 and P = 0.046, respectively). CONCLUSION: The local recurrence rate after PCA was significantly higher than after RAPN for T1 renal tumours. Incomplete treatment was the main criterion associated with recurrence. The recurrence rate may have been overestimated in the PCA group because of closer radiological follow-up in these patients.

Diffusion-weighted imaging of the prostate: should we use quantitative metrics to better characterize focal lesions originating in the peripheral zone?

PURPOSE: To compare inter-reader concordance and accuracy of qualitative diffusion-weighted (DW) PIRADSv2.0 score with those of quantitative DW-MRI for the diagnosis of peripheral zone prostate cancer. MATERIALS AND METHODS: Two radiologists independently assigned a DW-MRI-PIRADS score to 92 PZ-foci, in 74 patients (64.3±5.6 years old; median PSA level: 8 ng/ml, normal DRE in 70 men). A standardised ADCmean and nine ADC-derived parameters were measured, including ADCratios with the whole-prostate (WP-ADCratio) or the mirror-PZ (mirror-ADCratio) as reference areas. Surgical histology and MRI-TRUS fusion-biopsy were the reference for tumours and benign foci, respectively. Inter-reader agreement was assessed by the Cohen-kappa-coefficient and the intraclass correlation coefficient (ICC). Univariate-multivariate regressions determined the most predictive factor for cancer. RESULTS: Fifty lesions were malignant. Inter-reader concordance was fair for qualitative assessment, but excellent for quantitative assessment for all quantitative variables. At univariate analysis, ADCmean, WP-ADCratio and WL-ADCmean performed equally, but significantly better than the mirror-ADCratio (p<0.001). At multivariate analysis, the only independent variable significantly associated with malignancy was the whole-prostate-ADCratio. At a cut-off value of 0.68, sensitivity was 94-90 % and specificity was 60-38 % for readers 1 and 2, respectively. CONCLUSION: The whole-prostate-ADCratio improved the qualitative inter-reader concordance and characterisation of focal PZ-lesions. KEY POINTS: • Inter-reader concordance of DW PI-RADSv2.0 score for PZ lesions was only fair. • Using a standardised ADCmean measurement and derived DW-quantitative parameters, concordance was excellent. • The whole-prostate ADCratio performed significantly better than the mirror-ADCratio for cancer detection. • At a cut-off of 0.68, sensitivity values of WP-ADCratio were 94-90 %. • The whole-prostate ADCratio may circumvent variations of ADC metrics across centres.

[Cryoablation under local anesthesia of renal tumors]. / Cryothérapie sous anesthésie locale des tumeurs rénales.

Cryoablation under local anesthesia of renal tumors. The incidence of small renal tumors is increasing. These small tumors measuring less than 4 cm are typically slow-growing. The development of non-invasive percutaneous ablative techniques represents an alternative to active surveillance or surgery in at risk patients who are candidates to nephron sparing techniques. The intrinsic anesthetic properties of cryoablation make the procedure feasible under local anesthesia.

Cryothérapie sous anesthésie locale des tumeurs rénales. L'incidence du cancer du rein localisé et de petite taille est en constante augmentation. Ces tumeurs de moins de 4 cm sont classiquement peu agressives et leur potentiel de croissance est faible. Le développement des techniques ablatives percutanées comme la cryoablation a permis de proposer une alternative à la surveillance et à la chirurgie chez les patients fragiles nécessitant une préservation du capital néphronique. Les propriétés anesthésiques intrinsèques de la cryothérapie rendent la procédure faisable sous anesthésie locale.

Operative and oncological results and impact on treatment strategy of systematic renal tumor biopsy: Comparison between patients < and >75 years old.

BACKGROUND: Proper usage of renal tumor biopsy (RTB) remains to be determined in the setting of renal tumors diagnosis, particularly in the elderly population. The aim of the study was to evaluate the perioperative and pathological results of RTB in a population of patients over 75 and to compare the performance of the procedure to their younger counterparts. MATERIAL AND METHODS: Systematic RTB were prospectively performed in a single center between 2009 and 2012. Patients' and tumor characteristics, operative and pathological results were collected. Data were compared between patients under and over 75 years old. Particular attention was paid to influence of RTB on treatment decision-making. RESULTS: A total of 180 patients were included (137 patients <75 years and 43 > 75 years). Size of tumor, clinical stage, radiological aspect and RENAL score were not statistically different between patients under or over 75 years. No difference was observed between the 2 groups regarding complication rate (2.9% vs. 0%, respectively, P = 0.625). One hundred fifty-seven patients (87.2%) had a positive diagnosis at first RTB, with no difference between the 2 groups regarding histology (P = 0.942). After biopsy, only 73.1% of patients <75 years and 70.7% of patients >75 years had concordance between radiological and histological findings (P = 0.919). Treatment decision was challenged after RTB in 21.8% of patients <75 years and in 25.0% of patients >75 years. CONCLUSIONS: RTB was as safe and accurate in the eldest population, as it is in the general population, and should be performed routinely considering its influence on patient management strategy.