Detection of tetraploidization in chromophobe renal cell carcinoma: Insights and pitfalls.

Chromosomal losses resulting in a marked hypodiploidy are a specificity of chromophobe renal cell carcinoma (ChRCC), the third most frequent type of kidney cancer. Its detection is useful in challenging cases. However some ChRCC, especially the eosinophilic variant, do not exhibit hypodiploidy and deserve to be better explored. Using comparative genomic hybridization (array-CGH) we observed chromosomal gains in five cases of nonmetastatic ChRCC. Our objective was to determine whether these apparent chromosomal gains were instead losses within a near-polyploid genome. We performed a retrospective and prospective molecular study of 26 cases of ChRCC retrieved among 643 renal tumors (2012-2019). All tumors were analyzed using array-CGH (Agilent) and array-CGH (Affymetrix) coupled to single nucleotide polymorphism analysis (array-SNP). In silico manual centralization of the fluorescence ratio, fluorescence in situ hybridization (FISH) and next generation sequencing were made in the five cases suspected of polyploidy. Tetraploidization was observed in 19% of our series of ChRCC. None of the methods used individually could identify both chromosomal losses and tetraploidy. Only the combination of manual recentring of array-CGH and FISH provided relevant results. B-allele frequency results indicated that tetraploidization occurred secondarily to chromosomal losses in four cases while it preceded losses in one case. Tetraploidization is a frequent but underestimated phenomenon in ChRCC that may be overlooked using the individual standard genomic methods. Its potential clinical consequences are not identified yet. Whether the mechanisms that induce chromosomal losses in ChRCC are the same that generate tetraploidization is not known.

Robot-assisted Partial Nephrectomy for Hilar and Nonhilar Renal Masses: Comparison of Perioperative, Oncological, and Functional Results in a Multicentre Prospective Cohort (NEPRAH Study, UroCCR 175).

BACKGROUND AND OBJECTIVE: A hilar location for a renal tumour is sometimes viewed as a limiting factor for safe partial nephrectomy. Our aim was to evaluate perioperative, oncological, and functional outcomes of robot-assisted partial nephrectomy (RAPN) for hilar tumours (RAPN-H) in comparison to RAPN for nonhilar tumours (RAPN-NH). METHODS: We conducted an observational, multicentre cohort study using prospectively collected data from the French Research Network on Kidney Cancer (UroCCR). The registry includes data for 3551 patients who underwent RAPN for localised or locally advanced renal masses between 2010 and 2023 in 29 hospitals in France. We studied the impact of a hilar location on surgery, postoperative renal function, tumour characteristics, and survival. We also compared rates of trifecta achievement (warm ischaemia time [WIT] <25 min, negative surgical margins, and no perioperative complications) between the groups. Finally, we performed a subgroup analysis of RAPN without vascular clamping. Variables were compared in univariable analysis and using multivariable linear, logistic, and Cox proportional-hazards models adjusted for relevant patient and tumour covariates. KEY FINDINGS AND LIMITATIONS: The analytical population included 3451 patients, of whom 2773 underwent RAPN-NH and 678 underwent RAPN-H. Longer WIT (ß = 2.4 min; p < 0.01), longer operative time (ß = 11.4 min; p < 0.01) and a higher risk of postoperative complications (odds ratio 1.33; p = 0.05) were observed in the hilar group. Blood loss, the perioperative transfusion rate, postoperative changes in the estimated glomerular filtration rate, and trifecta achievement rates were comparable between the groups (p > 0.05). At mean follow-up of 31.9 mo, there was no significant difference in recurrence-free survival (hazard ratio [HR] 0.82, 95% confidence interval [CI] 0.58-1.2; p = 0.3), cancer-specific survival (HR 1.1, 95% CI 0.48-2.6; p = 0.79), or overall survival (HR 0.89, 95% CI 0.52-1.53; p = 0.69). CONCLUSIONS AND CLINICAL IMPLICATIONS: Patient and tumour characteristics rather than just hilar location should be the main determinants of the optimal surgical strategy for hilar tumours. PATIENT SUMMARY: We found that kidney tumours located close to major kidney blood vessels led to a longer operation and a higher risk of complications during robot-assisted surgery to remove the tumour. However, tumours in these locations were not related to a higher risk of kidney function loss, cancer recurrence, or death.

Preparing for the Worst: Management and Predictive Factors of Open Conversion During Minimally Invasive Renal Tumor Surgery (UroCCR-135 Study).

Background and objective: Data regarding open conversion (OC) during minimally invasive surgery (MIS) for renal tumors are reported from big databases, without precise description of the reason and management of OC. The objective of this study was to describe the rate, reasons, and perioperative outcomes of OC in a cohort of patients who underwent MIS for renal tumor initially. The secondary objective was to find the factors associated with OC. Methods: Between 2008 and 2022, of the 8566 patients included in the UroCCR project prospective database (NCT03293563), who underwent laparoscopic or robot-assisted minimally invasive partial (MIPN) or radical (MIRN) nephrectomy, 163 experienced OC. Each center was contacted to enlighten the context of OC: "emergency OC" implied an immediate life-threatening situation not reasonably manageable with MIS, otherwise "elective OC". To evaluate the predictive factors of OC, a 2:1 paired cohort on the UroCCR database was used. Key findings and limitations: The incidence rate of OC was 1.9% for all cases of MIS, 2.9% for MIRN, and 1.4% for MIPN. OC procedures were mostly elective (82.2%). The main reason for OC was a failure to progress due to anatomical difficulties (42.9%). Five patients (3.1%) died within 90 d after surgery. Increased body mass index (BMI; odds ratio [OR]: 1.05, 95% confidence interval [CI]: 1.01-1.09, p = 0.009) and cT stage (OR: 2.22, 95% CI: 1.24-4.25, p = 0.008) were independent predictive factors of OC. Conclusions and clinical implications: In MIS for renal tumors, OC was a rare event (1.9%), caused by various situations, leading to impaired perioperative outcomes. Emergency OC occurred once every 300 procedures. Increased BMI and cT stage were independent predictive factors of OC. Patient summary: The incidence rate of open conversion (OC) in minimally invasive surgery for renal tumors is low. Only 20% of OC procedures occur in case of emergency, and others are caused by various situations. Increased body mass index and cT stage were independent predictive factors of OC.

Giant Primary Scrotal Lipoma: A Rare Entity with Diagnostic Pitfalls.

Primary scrotal lipomas are rare. We describe the case of a 47-year-old male with a giant scrotal lipoma who underwent a surgical excision. We report the clinical and radiological approach as well as the treatment of this atypical benign tumor.