Search

Ureteral complications such as urinary leak, ureteral necrosis or ureteral stenosis are common complications after renal transplantation with major short- and long-term issues, including graft impairment and graft loss. At present, there is no agreement on the optimal management of ureteral complications. The aim of the current study was to evaluate the safety and efficacy of the self-expanding, large-caliber Allium ureteral stent in patients with ureteral complications following renal transplantation. In this retrospective study, the electronic database of Charité University Hospital was screened for patients receiving the self-expandable Allium ureteral stent in the transplant ureter after kidney transplantation between January 2016 and March 2022. Descriptive statistics were used to describe the outcomes. There were six men and four women with a median age of 61 years (interquartile range, 55 to 68 years). Nine out of 10 patients had ureteric stenosis, which was diagnosed at a median of two years (interquartile range 10 months to 9 years) following renal transplantation. The median operating time was 49 min (interquartile range, 30 to 60 min). Endoscopic Allium stent placement was successful in all patients with ureteric stenosis. The median length of stay in the hospital was four days (interquartile range 2 to 7 days). Only one patient (#5) had a postoperative grade IIIb Clavien–Dindo complication. Patients had follow-ups every 3 months with ultrasound and serum creatinine. Dislocation of the Allium stent was seen in four patients; all occurred within three months. Ultimately, three patients required ureteric re-implantation, two of which had early dislocation of the stent. Six patients are managed with a permanent Allium stent. The median dwell time was 11 months (interquartile range 3 to 20 months) and maximum dwell time was 23 months. The overall success rate was 60% (6 out of 10). According to our data, the Allium stent represents a safe and minimally invasive option with a success rate of 60%. It might, therefore, represent an alternative to DJ stents, nephrostomies or immediate re-implantation. As all dislocations occurred within three months, frequent early postoperative follow-up is required. [ABSTRACT FROM AUTHOR]

Background: To explore predictors of positive surgical margins (PSM) after robotic partial nephrectomy (PN) in a large multicenter international observational project, harnessing the Surface-Intermediate-Base (SIB) margin score to report the resection technique after PN in a standardized way. Methods: Data from consecutive patients with cT1-2N0M0 renal masses treated with PN from September 2014 to March 2015 at 16 tertiary referral centers and included in the SIB margin score International Consortium were prospectively collected. For the present study, only patients treated with robotic PN were included. Uni- and multivariable analysis were fitted to explore clinical and surgical predictors of PSMs after PN. Results: Overall, 289 patients were enrolled. Median (IQR) preoperative tumor size was 3.0 (2.3–4.2) cm and median (IQR) PADUA score was 8 (7–9). SIB scores of 0–2 (enucleation), 3–4 (enucleoresection) and 5 (resection) were reported in 53.3%, 27.3% and 19.4% of cases, respectively. A PSM was recorded in 18 (6.2%) patients. PSM rate was 4.5%, 11.4% and 3.6% in case of enucleation, enucleoresection and resection, respectively. Patients with PSMs had tumors with a higher rate of contact with the urinary collecting system (55.6% vs. 27.3%; p < 0.001) and a longer median warm ischemia time (22 vs. 16 min; p = 0.02) compared with patients with negative surgical margins, while no differences emerged between the two groups in terms of other tumor features (i.e., pathological diameter, PADUA score). In multivariable analysis, only enucleoresection (SIB score 3–4) versus enucleation (SIB score 0–2) was found to be an independent predictor of PSM at final pathology (HR: 2.68; 95% CI: 1.25–7.63; p = 0.04), while resection (SIB score 5) was not. Conclusions: In our experience, enucleoresection led to a higher risk of PSMs as compared to enucleation. Further studies are needed to assess the differential impacts of resection technique and surgeon's experience on margin status after robotic PN. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma (RCC) with sarcomatoid differentiation belongs to the most aggressive clinicopathologic phenotypes of RCC. It is characterized by a high propensity for primary metastasis and limited therapeutic options due to its relative resistance to established systemic targeted therapy. Most trials report on a poor median overall survival of 5 to 12 months. Sarcomatoid RCC can show the typical features of epithelial-mesenchymal transition (EMT) and may contain epithelial and mesenchymal features on both the morphological and immunhistochemical level. On the molecular level, next-generation sequencing confirmed differences in driver mutations between sarcomatoid RCC and non-sarcomatoid RCC. In contrast, mutational profiles within the epithelial and sarcomatoid components of sarcomatoid RCC were shown to be identical, with TP53 being the most frequently altered gene. These data suggest that both epithelial and sarcomatoid components of RCC originate from the same progenitor cell, segregating primarily according to the underlying histologic epithelial subtype of RCC (clear cell, papillary or chromophobe). Current studies have shown that sarcomatoid RCC express programmed death 1 (PD-1) and its ligand (PD-L1) at a much higher level than non-sarcomatoid RCC, suggesting that blockade of the PD-1/PD-L1 axis may be an attractive new therapeutic strategy. Preliminary results of clinical trials evaluating checkpoint inhibitors in patients with sarcomatoid RCC showed encouraging survival data and objective response and complete response rates of up to 62% and 18%, respectively. These findings may establish a new standard of care in the management of patients with sarcomatoid RCC. [ABSTRACT FROM AUTHOR]