ABSTRACT Purpose: Three-dimensional (3D) virtual models have recently gained consideration in the partial nephrectomy (PN) field as useful tools since they may potentially improve preoperative surgical planning and thus contributing to maximizing postoperative outcomes (1-5). The aim of the present study was to describe our first experience with 3D virtual models as preoperative guidance for robot-assisted PN. Materials and methods: Data of patients with renal mass amenable to robotic PN were prospectively collected at our Institution from January to April 2020. Using a dedicated web-based platform, abdominal CT-scan images were processed by M3DICS (Turin, Italy) and used to obtain 3D virtual models. 2D CT images and 3D models were separately assessed by two different highly experienced urologists to assess the PADUA score and risk category and to forecast the surgical strategy of the single cases, accordingly. Results: Overall, 30 patients were included in the study. Median tumor size was 4.3cm (range 1.3-11). Interestingly, 8 (26.4%) cases had their PADUA score downgraded when switching from 2D CT-scan to 3D virtual model assessment and 4 (13.4%) cases had also lowered their PADUA risk category. Moreover, preoperative off-clamp, selective clamping strategy and enucleation resection strategy increased from CT-scan to 3D evaluation. Conclusion: 3D virtual models are promising tools as they showed to offer a reliable assessment of surgical planning. However, the advantages offered by the 3D reconstruction appeared to be more evident as the complexity of the mass raises. These tools may ultimately increase tumor's selection for PN, particularly in highly complex renal masses. Disclosure of potential conflicts of interest: The authors declare they do not have conflict of interests. Informed consent: Informed consent was obtained from all individual participants included in the study. All the procedures were in accordance with the ethical standards of the institutional and national research Committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

ABSTRACT Purpose: The conservative management of localized renal masses has been recently widened to cT2 tumors showing encouraging functional and oncological outcomes (1). This video aims to report the conservative management of a highly complex renal tumor treated with robotic pure enucleation in our center, specifically focusing on preoperative work-up, video-reported surgical steps and perioperative outcomes. Materials and Methods: A 63 year-old lady underwent CT scan revealing a single 75 x 68mm, mainly endophytic, right renal mass dislocating the vascular pedicle (cT3a). Two renal arteries and two veins were identified. PADUA, RENAL and simplified SPARE scores were 14a, 12a and 12 respectively. Since the contralateral kidney was hypotrophic, the indication for nephron-sparing approach was considered absolute. Preoperative surgical planning included the employment of 3D-virtual models (2). Results: Operative time was 150 minutes and warm ischemia time was 25 minutes. No major complication occurred. Histopathological analysis revealed a cromophobe renal cell carcinoma with extension to perirenal fat tissue (pT3a). Resection technique was classified as pure enucleation since Surface-Intermediate-Base (SIB) score was 0-0-0 (3, 4). At seven-months follow-up no signs of local or systemic recurrence were recorded. Postoperative CT-scan revealed optimal parenchymal volume preservation with last creatinine blood level of 1.16mg/dL. Conclusion: This video highlights how, in experienced hands, robotic partial nephrectomy represents a feasible, effective treatment option for surgical management of highly complex renal tumors. The employment of intraoperative ultrasonography and 3D-virtual models allowed to accurately tailor surgical approach, improving the perception of tumor anatomy and its vascularization and maximizing perioperative outcomes.