Khareba G. Rationale for nephron sparing surgery strategy in patients with complex kidney tumors.

The purpose of the study was to improve the quality of treatment of patients with kidney cancer by developing optimal nephron sparing surgery tactics and formation of effective treatment algorithms for patients with this pathology. The efficacy and safety of nephron sparing surgery in malignant neoplasms of the kidneys of large (>70 mm) and very large (>100 mm) sizes, multifocal tumors, neoplasms with a completely intrarenal location, invasion to the renal sinus in patients with absolute or elective indications and depending to the age of the patients and their general condition were investigated. The indications for nephron sparing surgery for these types of tumors are presented. The effectiveness of nephron sparing surgery in renal cell carcinoma that spreads to the renal vein and inferior vena cava was investigated and their possibility was scientifically substantiated. A surgical technique of nephron sparing surgery with removal of tumors spreading to the venous system of the kidney using intrarenal and extrarenal thrombectomy was developed. New data on oncological results and complications of these operations are presented. The results of surgical treatment of patients with local recurrence after nephron sparing surgery were studied; the possibility of conducting repeated nephron sparing surgery and indications for it were substantiated. The efficacy and safety of extracorporeal nephron sparing surgery with autotransplantation of the kidney, as well as nephron sparing surgery for kidney tumors performed in situ in the conditions of hypothermic perfusion of the kidney were studied. The prognostic factors of the complexity of the operation, the occurrence of intra- and postoperative complications, local recurrence, metastasis, survival of the patients at nephron sparing surgery of kidney tumors were studied. A new scale for assessing the complexity of nephron sparing surgery (STORMS) was developed; it takes into account the criteria not previously used in nephrometric systems. The effectiveness of this scale was proven by a prospective study. Based on the STORMS scale, a surgical strategy for the use of nephron sparing surgery depending on the complexity of kidney tumors and the condition of the patients was developed.