Organ preserving surgery for kidney tumors is gaining popularity with the purpose of preserving kidney function and avoiding comorbidities associated with kidney failure. Considering the satisfactory technical, oncological and functional results of organ preserving surgery of locally advanced kidney tumors, its use is increasing annually on the background of improvements in surgical technique and experience gained by surgeons. Technical feasibility of performing organ preserving surgery, its complexity, its possible complications, and its usefulness in general depend on a large number of factors. The usage of objective and reproducible techniques prevents the subjectivity of evaluation of the surgical situation and allows standardization of treatment tactics. Thus, nephrometry scales are used to provide the urologist with information about the complexity of future surgery on the anatomic and topographic characteristics of parenchymal tumors of the kidney and help determine the type of surgery. The article presents a comparative overview of modern RENAL, PADUA, C-index and "contact surface area" nephrometry systems. These nephrometric systems are similarly effective for risk prediction. Organ preserving surgery correlates with blood loss, duration of surgery, time of renal ischemia, number of complications, duration of inpatient treatment, time of renal ischemia, and conversion of organ preserving surgery to nephrectomy. All nephrometric systems correlate well with each other, but the data suggest that the "contact surface area" may be a more accurate system in predicting perioperative complications. Nephrometry also correlates with post-operative renal function and some systems are capable of predicting the malignancy of the renal neoplasm and are associated with differentiation and subtype of renal cancer. Nephrometric systems are effective in calculating done by urologists-surgeons regardless of radiologists. Nephrometry systems have become a standardized tool but are not widely used by radiologists. Interdisciplinary agreement between urologists and radiologists can be improved by developing new nephrometric systems. Prospective studies are now being conducted in this area. Conclusion. None of the current nephrometric systems can be considered perfect and studies are continuing in this regard. It is determined that the volume of stored kidney parenchyma after organ preserving surgery is a significant indicator for choosing the tactics of surgical treatment of patients. The use of nephrometry systems should be recommended to determine the complexity of the tumor when planning organ preserving kidney surgery, although international recommendations for organ preserving surgery are still based on the clinical size of the tumor. Although nephrometric systems are similarly effective, none of them fully meet the needs of urologists involved in organ preserving renal tumor surgery, and further research is needed in this area.

Keywords: kidney tumors, organ preserving surgery, nephrometric systems

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1. Canter D, Kutikov A, Manley B, Egleston B, Simhan J, Smaldone M, et al. Utility of the R.E.N.A.L. nephrometry scoring system in objectifying treatment decision-making of the enhancing renal mass. Urology. 2011; 78: 1089–94. PMID: 22054378. PMCID: PMC3477543. https://doi.org/10.1016/j.urology.2011.04.035
2. Lieser G, Simmons MN. Developments in kidney tumor nephrometry. Postgrad Med. 2011; 123: 35–42. PMID: 21566414. https://doi.org/10.3810/pgm.2011.05.2282
3. Kutikov A, Uzzo RG. The R.E.N.A.L. nephrometry score: a comprehensive standardized system for quantitating renal tumor size, location and depth. J Urol. 2009; 182: 844-53. https://doi.org/10.1016/j.juro.2009.05.035
4. Ficarra V, Novara G, Secco S, Macchi V, Porzionato A, De Caro R, et al. Preoperative aspects and dimensions used for an anatomical (PADUA) classification of renal tumours in patients who are candidates for nephron-sparing surgery. Eur Urol. 2009; 56: 786–93. PMID: 19665284. https://doi.org/10.1016/j.eururo.2009.07.040
5. Simmons MN, Ching CB, Samplaski MK, Park CH, Gill IS. Kidney tumor location measurement using the C index method. J Urol. 2010; 183: 1708–13.
6. Leslie S, Gill IS, de Castro Abreu AL, Rahmanuddin S, Gill KS, Nguyen M, et al. Renal tumor contact surface area: a novel parameter for predicting complexity and outcomes of partial nephrectomy. Eur Urol. 2014; 66: 884–93. PMID: 24680360. https://doi.org/10.1016/j.eururo.2014.03.010
7. Bylund JR, Gayheart D, Fleming T, Venkatesh R, Preston DM, Strup SE, et al. Association of tumor size, location, R.E.N.A.L. PADUA and centrality index score with perioperative outcomes and postoperative renal function. J Urol. 2012; 188: 1684–9. PMID: 22998902. https://doi.org/10.1016/j.juro.2012.07.043
8. Lavallée LT, Desantis D, Kamal F, Blew B, Watterson J, Mallick R, et al. The association between renal tumour scoring systems and ischemia time during open partial nephrectomy. Can Urol Assoc J. 2013; 7: E207–14. PMID: 22630339. PMCID: PMC3650784. https://doi.org/10.5489/cuaj.11202
9. Png KS, Bahler CD, Milgrom DP, Lucas SM, Sundaram C. The role of R.E.N.A.L. nephrometry score in the era of robot assisted partial nephrectomy. J Endourol. 2013; 27: 304–8.
10. Klatte T, Ficarra V, Gratzke C, Kaouk J, Kutikov A, Macchi V, et al. A literature review of renal surgical anatomy and surgical strategies for partial nephrectomy. Eur Urol. 2015; 68: 980-92. PMID: 25911061. PMCID: PMC4994971. https://doi.org/10.1016/j.eururo.2015.04.010
11. Hayn MH, Schwaab T, Underwood W, Kim HL. RENAL nephrometry score predicts surgical outcomes of laparoscopic partial nephrectomy. BJU Int. 2011; 108: 876–81.
12. Simhan J, Smaldone MC, Tsai KJ, Canter DJ, Li T, Kutikov A, et al. Objective measures of renal mass anatomic complexity predict rates of major complications following partial nephrectomy. Eur Urol. 2011; 60: 724–30. PMID: 21621910. PMCID: PMC3319121. https://doi.org/10.1016/j.eururo.2011.05.030
13. Hew MN, Baseskioglu B, Barwari K, Axwijk PH, Can C, Horenblas S, et al. Critical appraisal of the PADUA classification and assessment of the R.E.N.A.L. nephrometry score in patients undergoing partial nephrectomy. J Urol. 2011 Jul; 186(1): 42-6.
14. Kruck S, Anastasiadis AG, Walcher U, Stenzl A, Herrmann TR, Nagele U. Laparoscopic partial nephrectomy: risk stratification according to patient and tumor characteristics. World J Urol. 2012; 30: 639–46.
15. Long JA, Arnoux V, Fiard G, Autorino R, Descotes JL, Rambeaud JJ, et al. External validation of the RENAL nephrometry score in renal tumours treated by partial nephrectomy. BJU Int. 2013; 111: 233–9. PMID: 22788546. https://doi.org/10.1111/j.1464-410X.2012.11339.x
16. Stroup SP, Palazzi K, Kopp RP, Mehrazin R, Santomauro M, Cohen SA, et al. RENAL nephrometry score is associated with operative approach for partial nephrectomy and urine leak. Urology. 2012; 80: 151–6. PMID: 22748871. https://doi.org/10.1016/j.urology.2012.04.026
17. Mayer WA, Godoy G, Choi JM, Goh AC, Bian SX, Link RE. Higher RENAL Nephrometry Score is predictive of longer warm ischemia time and collecting system entry during laparoscopic and robotic-assisted partial nephrectomy. Urology. 2012; 79: 1052–6.
18. Liu ZW, Olweny EO, Yin G, Faddegon S, Tan YK, Han WK, et al. Prediction of perioperative outcomes following minimally invasive partial nephrectomy: role of the R.E.N.A. L nephrometry score. World J Urol. 2013; 31: 1183–9. PMID: 22544340. https://doi.org/10.1007/s00345-012-0876-3
19. Altunrende F, Laydner H, Hernandez AV, Autorino R, Khanna R, White MA, et al. Correlation of the RENAL nephrometry score with warm ischemia time after robotic partial nephrectomy. World J Urol. 2013; 31: 1165–9. PMID: 22527672. https://doi.org/10.1007/s00345-012-0867-4
20. Mufarrij PW, Krane LS, Rajamahanty S, Hemal AK. Does nephrometry scoring of renal tumors predict outcomes in patients selected for robot-assisted partial nephrectomy? J Endourol. 2011; 25: 1649–53. PMID: 21851270. https://doi.org/10.1089/end.2011.0003
21. Bruner B, Breau RH, Lohse CM, Leibovich BC, Blute ML. Renal nephrometry score is associated with urine leak after partial nephrectomy. BJU Int. 2011; 108: 67–72.
22. Okhunov Z, Rais-Bahrami S, George AK, Waingankar N, Duty B, Montag S, et al. The comparison of three renal tumor scoring systems: C-Index, P.A.D.U.A., and R.E.N.A.L. nephrometry scores. J Endourol. 2011 Dec; 25(12): 1921-4.
23. Ficarra V, Bhayani S, Porter J, Buffi N, Lee R, Cestari A, et al. Predictors of warm ischemia time and perioperative complications in a multicenter, international series of robot-assisted partial nephrectomy. Eur Urol. 2012; 61: 395–402. PMID: 22079308. https://doi.org/10.1016/j.eururo.2011.10.046
24. Waldert M, Waalkes S, Klatte T, Kuczyk MA, Weibl P, Schüller G, et al. External validation of the preoperative anatomical classification for prediction of complications related to nephron-sparing surgery. World J Urol. 2010; 28: 531–5. PMID: 20607246. https://doi.org/10.1007/s00345-010-0577-8
25. Kong W, Zhang J, Dong B, Chen Y, Xue W, Liu D, et al. Application of a standardized anatomical classification in a Chinese partial nephrectomy series. Int J Urol. 2012; 19: 551–8. PMID: 22462720. https://doi.org/10.1111/j.1442-2042.2012.02973.x
26. Mottrie A, Schatteman P, De Wil P, De Troyer B, Novara G, Ficarra V. Validation of the preoperative aspects and dimensions used for an anatomical (PADUA) score in a robot-assisted partial nephrectomy series. World J Urol. 2013; 31: 799–804.
27. Tyritzis SI, Papadoukakis S, Katafigiotis I, Adamakis I, Anastasiou I, Stravodimos KG, et al. Implementation and external validation of Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) score for predicting complications in 74 consecutive partial nephrectomies. BJU Int. 2012; 109: 1813–8. PMID: 21981696. https://doi.org/10.1111/j.1464-410X.2011.10644.x
28. Minervini A, Vittori G, Salvi M, Sebastianelli A, Tuccio A, Siena G, et al. Analysis of surgical complications of renal tumor enucleation with standardized instruments and external validation of PADUA classification. Ann Surg Oncol. 2013; 20: 1729–36. PMID: 23263701. https://doi.org/10.1245/s10434-012-2801-9
29. Simmons MN, Hillyer SP, Lee BH, Fergany AF, Kaouk J, Campbell SC. Nephrometry score is associated with volume loss and functional recovery after partial nephrectomy. J Urol. 2012; 188: 39–44.
30. Kutikov A, Smaldone MC, Egleston BL, Manley BJ, Canter DJ, Simhan J, et al. Anatomic features of enhancing renal masses predict malignant and high-grade pathology: a preoperative nomogram using the RENAL nephrometry score. Eur Urol. 2011; 60: 241–8. PMID: 21458155. PMCID: PMC3124570. https://doi.org/10.1016/j.eururo.2011.03.029
31. Wang HK, Zhu Y, Yao XD, Zhang SL, Dai B, Zhang HL, et al. External validation of a nomogram using RENAL nephrometry score to predict high grade renal cell carcinoma. J Urol. 2012; 187: 1555–60. PMID: 22425078. https://doi.org/10.1016/j.juro.2011.12.099
32. Satasivam P, Sengupta S, Rajarubendra N, Chia PH, Munshey A, Bolton D. Renal lesions with low R.E.N.A.L. Nephrometry score are associated with more indolent renal cell carcinomas (RCCs) or benign histology: findings in an Australian cohort. BJU Int. 2012; 109(Suppl 3): 44–7.
33. Mullins JK, Kaouk JH, Bhayani S, Rogers CG, Stifelman MD, Pierorazio PM, et al. Tumor complexity predicts malignant disease for small renal masses. J Urol. 2012; 188: 2072–6. PMID: 23083863. https://doi.org/10.1016/j.juro.2012.08.027
34. Khandwala YS, Jeong IG, Kim JH, Han DH, Li S, Wang Y, et al. The incidence of unsuccessful partial nephrectomy within the United States: a nationwide population-based analysis from 2003 to 2015. Urol Oncol. 2017; 35: 672.e7-672.e13. PMID: 28889920. https://doi.org/10.1016/j.urolonc.2017.08.014
35. Arora S, Chun B, Ahlawat RK, Abaza R, Adshead J, Porter JR, et al. Conversion of robot-assisted partial nephrectomy to radical nephrectomy: a prospective multi-institutional study. Urology. 2018; 113: 85-90. PMID: 29284123. https://doi.org/0.1016/j.urology.2017.11.046
36. Dahlkamp L, Haeuser L, Winnekendonk G, von Bodman C, Frey UH, Epplen R, et al. Interdisciplinary comparison of PADUA and R.E.N.A.L. scoring systems for prediction of conversion to nephrectomy in patients with renal mass scheduled for nephron sparing surgery. J Urol. 2019; 202(5): 890-8. PMID: 31145034. https://doi.org/10.1097/JU.0000000000000361
37. Ficarra V, Rossanese M, Giannarini G, Crestani A, Simonato A, Inferrera A. The use of nephrometry scoring systems can help urologists predict the risk of conversion to radical nephrectomy in patients scheduled for partial nephrectomy. Ann Transl Med. 2019; 7(Suppl 6): S213. https://doi.org/10.21037/atm.2019.08.92
38. Ficarra V, Porpiglia F, Crestani A, Minervini A, Antonelli A, Longo N, et al. The Simplified PADUA REnal (SPARE) nephrometry system: a novel classification of parenchymal renal tumours suitable for partial nephrectomy. BJU Int. 2019. [Epub ahead of print]. PMID: 30963680. https://doi.org/10.1111/bju.14772
39. Stakhovskiy EO, Voylenko OA, Vitruk YuV, Stakhovskiy OE. Zastosuvannya nefrometriyi dlya viboru taktiki likuvannya khvorikh z privodu nirkovoklitinnogo raku [The use of nephrometry for the choice of tactics for the treatment of patients with renal cell cancer]. Klinichna khirurgiya. 2015; 3: 55–60. [Ukrainian]
40. Porpiglia F, Amparore D, Checcucci E, Manfredi M, Stura I, Migliaretti G, et al. Three-dimensional virtual imaging of the renal tumors: a new tool to improve the accuracy of nephrometric scores. BJU Int. 2019 Dec; 124(6): 945-54. https://doi.org/10.1111/bju.14894
41. EAU Guidelines. Edn presented at the EAU Annual Congress Barcelona 2019.