Anatrophic nephrotomy as nephron-sparing approach for complete removal of intraparenchymal renal tumors

Abstract

InTRODUcTIOnWith the development of imaging diagnosis techniques, and the higher number of requested exams, there has been a growth of the incidence of small renal tumors, and an increase of the indication of nephron-sparing surgery, with excellent oncological and functional outcomes (1). In the last years, the incidental lesions are responsible for more than 60% of kidney tumors and 80% of these are in stages I and II (2).Nephron-sparing renal surgery has been increasingly used for small renal mass (<4 cm) and, in selected cases, up to 7 cm renal tumors with similar oncological outcomes compared to radical nephrectomy, (3-5) with small complication ratio (6). The 5-year recurrence-free survival is approximately 96% for lesions smaller than 4 cm, and of 83% for lesions from 4 to 7 cm (7).However, renal occult tumors diagnosed by imaging techniques represent greater technical diffi culties for localization and resection, and may Objective: Partial nephrectomy for small kidney tumors has increased in the last decades, and the approach to non-palpable endophytic tumors became a challenge, with larger chances of positive margins or complications. The aim of this study is to describe an alternative nephron-sparing approach for small endophytic kidney tumors through anatrophic nephrotomy. Patients and Methods: A retrospective analysis of patients undergoing partial nephrectomy at our institution was performed and the subjects with endophytic tumors treated with anatrophic nephrotomy were identifi ed. Patient demographics, perioperative outcomes and oncological results were evaluated. Results: Among the partial nephrectomies performed for intraparenchymal tumors between 06/2006 and 06/2010, ten patients were submitted to anatrophic nephrotomy. The mean patient age was 42 yrs, and the mean tumor size was 2.3 cm. Mean warm ischemia time was 22.4 min and the histopathological analysis showed 80% of clear cell carcinomas. At a mean follow-up of 36 months, no signifi cant creatinine changes or local or systemic recurrences were observed. Conclusion: The operative technique described is a safe and effective nephronsparing option for complete removal of endophytic renal tumors. Anatrophic Nephrotomy as ABSTRAcTARTIcLe InfO _______________________________________________________________ _____________________

Anatomical background of ovine kidney for use as animal model: analysis of arterial segmentation, proportional volume of each segment and arterial injury after cranial pole partial nephrectomy

“…This species may be particularly interesting for using in anatrophic nephrolithotomy studies. As it was observed, the division on anterior and posterior segments, leaves a (so-called) avascular plane (Brodel's line) similarly to what is found in human kidney (25).…”

Partial Nephrectomy Versus Radical Nephrectomy for Endophytic Renal Tumors: Comparison of Operative, Functional, and Oncological Outcomes by Propensity Score Matching Analysis

“…The following surgical difficulties are the reasons for a higher incidence of high-grade complications in the PN group: first, ERTs are generally small in size, deep in location, and have invisible boundaries; thus, it takes a long time to locate and remove the tumor. Furthermore, the resection margin can be positive because of the indistinct tumor expansion during its removal ( 8 ), which has a major impact on the prognosis. Second, ERTs are prone to be close to the collecting system and renal sinus, wherein they are highly close to or even infiltrate into the secondary and tertiary renal arteries and veins.…”

“…Due to its highly complex anatomy, it is difficult to remove tumors and suture incised renal parenchyma, which requires considerable expertise and higher technical skills. Furthermore, these cases are related to higher intraoperative and perioperative complication rates, including positive resection margin caused by an unclear boundary, massive bleeding due to an accidental vascular injury, urine leakage caused by an accidental pelvicalyceal system injury, and renal vascular occlusion caused by inappropriate suture (7)(8)(9). Given the above risks and challenges, in the past, most urologists preferred RN for ERMs to avoid serious complications (10,11).…”

Pilot study comparing the two hemostatic agents in patients undergoing partial nephrectomy

“…Complication rates associated with NSS ( e . g ., overall morbidity rate, hospital stay, blood losses, and frequency of acute renal failure) have decreased significantly [23,24], which may be attributed to the greater experience of the urologist [25] or perhaps due to the incorporation of various new technologies ( i . e ., hemostatic agents, lasers, etc.)…”