Cancer - Kidney(비디오) (V-016) 완전 내장성 신종양에서의 부분 신절제술 서울대학교 의과대학 비뇨의학교실 정규환, 유상현, 윤현식, 박대형, 서준교, 황영철, 육형동, 정창욱, 구자현, 김현회, 곽철 Purpose: We evaluate surgical outcomes in patients who underwent partial nephrectomy for totally endophytic renal mass. . Materials and Methods: We reviewed 601 patients with at least 3 months of follow-up after partial nephrectomy for renal mass by a single surgeon from March 2016 to March 2020. All data was extracted from Seoul National University Prospectively Enrolled Registry for Renal Cell Carcinoma – Nephrectomy (SUPER-RCC-Nx). There were 49 (8.2%) patients with totally endophytic renal mass. We divided patients into 2 groups according to the ‘E’ score and ‘N’ score of R.E.N.A.L score index (group A: Endophytic mass with ‘E’=3 and ‘N’=3, group B: others). Pre-operative characteristics and post-operative early outcomes were compared and analyzed. Results: Mean size of mass in CT was 2.9cm in group A and 3.5cm in group B (p=0.003). In other pre-operative characteristics, there were no significant difference between two groups. Mean ischemic time was 26.3 minutes in group A and 18.3 minutes in group B (p<0.001). Mean follow up duration in group A was 18.6 months and 19.2 months in group B (p=0.777). There was no recur in group A and 10 in group B (p=1.000). There were 5 cases (10.2%) in group A and 18 cases (3.3%) in group B (p=0.032) of complications of grade 3 or higher for Clavien-Dindo classification for 90 days after surgery. There was no 90 days mortality in both groups. In end stage renal disease (ESRD) progression, 1 (2.0%) in group A and 4 (0.7%) in group B found (p=0.347). Conclusions: If surgeon’s experience in enough and skillful, partial nephrectomy in totally endophytic mass seems like acceptable. Enucleation is important procedure in this operation for negative surgical margin and to avoid tumor violation. keywords : Partial nephrectomy, Totally endophytic renal mass, Enucleation