Comparison of transperitoneal and retroperitoneal robot partial nephrectomy for kidney tumors

Article information

Kosin Med J. 2023;38(4):274-277
Publication date (electronic) : 2023 December 20
doi :
Department of Urology, Kosin University Gospel Hospital, Kosin University College of Medicine, Busan, Korea
Corresponding Author: Su Hwan Kang, MD Department of Urology, Kosin University College of Medicine, 262 Gamcheon-ro, Seo-gu, Busan 49267, Korea Tel: +82-51-990-5077 Fax: +82-51-990-3994 E-mail:
Received 2023 September 19; Revised 2023 October 24; Accepted 2023 October 24.



Surgical techniques for small kidney tumors have been developed for decades, from open to robotic surgery. There are two approaches for partial nephrectomy: transperitoneal and retroperitoneal. We divided robotic partial nephrectomy cases into transperitoneal robotic partial nephrectomy (TRPN) and retroperitoneal robotic partial nephrectomy (RRPN) and compared the outcomes.


We retrospectively evaluated patients who underwent robotic partial nephrectomy at our hospital between November 2019 and May 2022. We reviewed patients’ demographic and perioperative data.


Seventy robotic partial nephrectomies were performed (35 TRPN and 35 RRPN). There were significant differences in operation time, estimated blood loss (EBL), tumor size, and the RENAL Nephrometry Score (RNS) between those who underwent TRPN and those who underwent RRPN. Larger tumors were noted in the TRPN group, and the RNS was higher. In contrast, the operation time was shorter, EBL was lower, and tumors were more likely to be located in the posterior and lower portions in the RRPN group than in the TRPN group.


In our study, RRPN had advantages over TRPN in terms of operation time and EBL. However, TRPN tended to be performed rather than RRPN for tumors that were more complex in terms of size or RNS. Although the choice between RRPN and TRPN depends on the surgeon's preference, RRPN seems effective for treating small kidney tumors if selected appropriately.


Radical nephrectomy has been the standard treatment for kidney cancer for decades since Robson et al. [1] introduced it as a treatment for renal cell carcinoma. Since then, partial nephrectomy, which is more nephron-sparing than radical nephrectomy, for small kidney tumors has been actively debated and considered non-inferior to radical nephrectomy in surgical outcomes, including overall survival and cancer-specific survival [2,3]. Although partial nephrectomy is mainly performed for clinical T1 tumors, it is also performed for clinical T2 tumors and has been increasingly performed for small kidney tumors because of the advantage of nephron preservation [4-6]. The surgical technique of partial nephrectomy has evolved in recent decades from open partial nephrectomy to laparoscopic and robotic partial nephrectomy [7,8].

Partial nephrectomy can be divided into the peritoneal or retroperitoneal approach [9]. The peritoneal approach has traditionally been practiced more than the retroperitoneal approach because of a wider surgical space and more familiar anatomical landmarks. Conversely, while the retroperitoneal approach has a narrower surgical space, it allows direct access to the renal artery, and intraperitoneal organs such as the intestine, spleen, and liver can be avoided. Therefore, there is less pressure on intraperitoneal organ injury with the retroperitoneal approach, which is beneficial for restoring bowel function after surgery [10,11].

We conducted a retrospective study to compare transperitoneal robotic partial nephrectomy (TRPN) and retroperitoneal robotic partial nephrectomy (RRPN) performed by a single surgeon at our institution to investigate potential differences in tumor characteristics and surgical outcomes between the two procedures.


Ethical statements: This study was approved by the Institutional Review Board of Kosin University Gospel Hospital (IRB No. KUGH 2023-06-026) and was conducted in accordance with the recent Declaration of Helsinki. Informed consent was waived by the board.

We performed a retrospective evaluation using the electronic medical records of patients who underwent robotic partial nephrectomy from November 2019, when RRPN was first performed in our hospital, to May 2022. RRPN was performed by a single urologist (SHK).

We reviewed demographic and perioperative data, such as age, hospital stay, operation time (skin-to-skin), warm ischemic time (WIT), estimated blood loss (EBL) during surgery, positive surgical margin (PSM), tumor size, RENAL Nephrometry Score (RNS), tumor location, preoperative and postoperative estimated glomerular filtration rate (eGFR), and complications. Hospital stay was defined as the number of resource days from the day of surgery to the day of discharge. RNS was obtained with the method introduced by Kutikov and Uzzo in 2009 [12]. Complications were classified according to the Clavien-Dindo classification system [13]. Tumor location was assessed using computed tomography or magnetic resonance imaging and classified as upper/lower/unassessable and medial/lateral/unassessable. Preoperative eGFR was assessed within 1 month before surgery, and postoperative eGFR was assessed within 1 week before discharge. To assess postoperative eGFR change, we defined eGFR change as the postoperative eGFR value minus the preoperative value.

Statistical analysis was conducted with IBM SPSS. Mann-Whitney U test was used for quantitative variables, and the chi-square test for categorical variables. A significant p-value was determined as less than 0.05.


Seventy robotic partial nephrectomies (35 TRPN and 35 RRPN) were performed. All surgeries were carried out using the da Vinci Xi system (Intuitive Surgical).

The median hospital stays after surgery (both TRPN and RRPN) was 8.38 days, operation time 148 minutes, WIT 27.26 minutes, EBL 278 mL, tumor size 2.37 cm, RNS score 5.89, eGFR change (postoperative eGFR–preoperative eGFR) –1.11. The two groups had statistically significant differences in operation time, EBL, tumor size, and RNS. However, no significant difference in age, length of hospital stays, WIT, PSM rate, eGFR changes, and complication rates was detected between the groups. Larger tumors were noted in the TRPN group, and the RNS was higher. In contrast, the operation time was shorter and EBL was lower in the RRPN group. In the RRPN group, the tumor tended to be significantly more posterior and lower, but the PSM and complication rates were not significantly different (Table 1).

Clinical characteristics and results of the TRPN and RRPN groups

There were two cases of PSM in the TRPN group and two cases in the RRPN group, but only one case of clear cell renal cell carcinoma in the TRPN group was confirmed as an angiomyolipoma by histopathological examination. There were no Clavien-Dindo grade 3 or higher complications in the TRPN group and three cases (urine leakage at the surgical site) in the RRPN group. Ureteral stenting or percutaneous nephrostomy was performed for the three cases.


TRPN requires more dissection than RRPN, particularly when the tumor is located in the posterior portion. This difference in dissection may result in a shorter operation time (128±39 minutes vs. 169±51 minutes, p<0.001) and less EBL (136±164 mL vs. 420±641 mL, p=0.015) for RRPN. However, if the tumor is located in the anterior or superior portion, using the RRPN approach is difficult. This is why a significantly higher proportion of tumors in the posterior or inferior segments was noted in the RRPN group compared to the TRPN group. In addition, the narrower surgical space in RRPN compared to TRPN tended to favor smaller tumors (2.77±1.54 cm vs. 1.96±0.91 cm, p=0.01). The results of our study are similar to those of other studies. Choi et al. [14] compared TRPN and RRPN conducted by a single surgeon. According to these authors, although there was no significant difference in tumor complexity or location between the two groups, the RRPN group had better results in terms of operation time (273 minutes vs. 244 minutes, p<0.001), WIT (21 minutes vs. 19 minutes, p=0.008), and EBL (150 mL vs. 100 mL, p=0.003). In Harke et al.’s multicenter analysis [15], the RRPN group had a shorter median operation time than the TRPN group after propensity score matching (139 minutes vs. 119 minutes, p<0.001), which included tumor characteristics and shorter hospitalization (9 days vs. 8 days, p<0.001). Zhou et al.'s meta-analysis of 21 studies [16] also showed significant benefits of RRPN in terms of operation time, length of hospitalization, and EBL. Although the studies had some variations, overall, RRPN outperformed TRPN in operative time and EBL. The RRPN group displayed a shorter operation time, consistent with prior research [14-16]. However, tumor size and RNS were greater in the TRPN group in our study. Thus, caution must be exercised when interpreting these results, as these variables may affect operation time. The EBL was also higher in the TRPN group, similar to other studies [14-16]. This finding could also be attributed to tumor complexity, such as tumor size and RNS.

Our study has some limitations. The study was a retrospective analysis, and patients were divided into two groups based on the surgical method used in their case. The decision regarding surgical method was influenced by the size and location of the tumor, which led to variations in tumor size, tumor complexity as measured by RNS, and tumor location between the groups. Conducting a retrospective comparison of the two surgical methods under similar conditions is infeasible because of the impact of tumor size and location on the choice of surgical procedure. A large-scale randomized prospective study in which tumor size or location is matched between the study groups would elucidate the advantages and disadvantages of the two surgical techniques based on tumor location and complexity.

In our study, RRPN had advantages over TRPN in terms of operation time and EBL. RRPN is usually performed for renal masses in the posterior or lower portions. However, there is a tendency to perform TRPN rather than RRPN for tumors that are more complex in terms of size or RNS. Although the choice between RRPN and TRPN depends on the surgeon's preference, RRPN seems effective for treating small kidney tumors if selected appropriately.


Conflicts of interest

No potential conflict of interest relevant to this article was reported.



Author contributions

Conceptualization: YS, SHK, TSK. Data curation: YS. Formal analysis: YS. Investigation: YS, SHK, TSK, DHK, SBK. Methodology: YS, SHK, TSK. Project administration: SHK. Resources: YS, SHK. Supervision: SHK, TSK. Visualization: YS. Writing - original draft: YS, SHK. Writing - review & editing: YS, SHK, TSK, DHK, SBK. Approval of final manuscript: all authors.


1. Robson CJ, Churchill BM, Anderson W. The results of radical nephrectomy for renal cell carcinoma. J Urol 1969;101:297–301.
2. Lee CT, Katz J, Shi W, Thaler HT, Reuter VE, Russo P. Surgical management of renal tumors 4 cm. or less in a contemporary cohort. J Urol 2000;163:730–6.
3. Kunath F, Schmidt S, Krabbe LM, Miernik A, Dahm P, Cleves A, et al. Partial nephrectomy versus radical nephrectomy for clinical localised renal masses. Cochrane Database Syst Rev 2017;5:CD012045.
4. Campbell S, Uzzo RG, Allaf ME, Bass EB, Cadeddu JA, Chang A, et al. Renal mass and localized renal cancer: AUA Guideline. J Urol 2017;198:520–9.
5. Klett DE, Tsivian M, Packiam VT, Lohse CM, Ahmed ME, Potretzke TA, et al. Partial versus radical nephrectomy in clinical T2 renal masses. Int J Urol 2021;28:1149–54.
6. Herr HW. A history of partial nephrectomy for renal tumors. J Urol 2005;173:705–8.
7. Lane BR, Campbell SC, Gill IS. 10-Year oncologic outcomes after laparoscopic and open partial nephrectomy. J Urol 2013;190:44–9.
8. Leow JJ, Heah NH, Chang SL, Chong YL, Png KS. Outcomes of robotic versus laparoscopic partial nephrectomy: an updated meta-analysis of 4,919 patients. J Urol 2016;196:1371–7.
9. Gill IS, Delworth MG, Munch LC. Laparoscopic retroperitoneal partial nephrectomy. J Urol 1994;152(5 Pt 1):1539–42.
10. Hu JC, Treat E, Filson CP, McLaren I, Xiong S, Stepanian S, et al. Technique and outcomes of robot-assisted retroperitoneoscopic partial nephrectomy: a multicenter study. Eur Urol 2014;66:542–9.
11. Stroup SP, Hamilton ZA, Marshall MT, Lee HJ, Berquist SW, Hassan AS, et al. Comparison of retroperitoneal and transperitoneal robotic partial nephrectomy for Pentafecta perioperative and renal functional outcomes. World J Urol 2017;35:1721–8.
12. 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.
13. Dindo D, Demartines N, Clavien PA. Classification of surgical complications: a new proposal with evaluation in a cohort of 6336 patients and results of a survey. Ann Surg 2004;240:205–13.
14. Choi CI, Kang M, Sung HH, Jeon HG, Jeong BC, Jeon SS, et al. Comparison by pentafecta criteria of transperitoneal and retroperitoneal robotic partial nephrectomy for large renal tumors. J Endourol 2020;34:175–83.
15. Harke NN, Darr C, Radtke JP, von Ostau N, Schiefelbein F, Eraky A, et al. Retroperitoneal versus transperitoneal robotic partial nephrectomy: a multicenter matched-pair analysis. Eur Urol Focus 2021;7:1363–70.
16. Zhou J, Liu ZH, Cao DH, Peng ZF, Song P, Yang L, et al. Retroperitoneal or transperitoneal approach in robot-assisted partial nephrectomy, which one is better? Cancer Med 2021;10:3299–308.

Article information Continued

Table 1.

Clinical characteristics and results of the TRPN and RRPN groups

Characteristic TRPN RRPN Overall p-value
Age (yr) 57.46±12.65 63.37±12.46 60.41±12.81 0.053
Hospital stays after surgery (day) 7.54±0.98 9.23±6.64 8.38±4.79 0.073
Operation time (min) 169±51 128±39 148±50 <0.001
Warm ischemic time (min) 29.56±7.76 25.29±5.73 27.26±6.99 0.056
Off clamp 17 (48.57) 14 (40.00) 31 (44.29) 0.47
Estimated blood loss (mL) 420±641 136±164 278±485 0.015
Positive surgical margin 2 (5.71) 2 (5.71) 4 (5.71) 1.000
Tumor size (cm) 2.77±1.54 1.96±0.91 2.37±1.32 0.01
RENAL Nephrometry Score 6.34±1.53 5.43±1.77 5.89±1.71 0.024
 Anterior or posterior <0.001
  Anterior 15 (42.86) 5 (14.29) 20 (28.57)
  Posterior 8 (22.86) 24 (68.57) 32 (45.71)
  Non-assessable 12 (32.29) 6 (17.14) 18 (25.71)
 Upper or lower 0.031
  Upper 14 (40.00) 5 (14.29) 19 (27.14)
  Lower 17 (48.57) 22 (62.86) 39 (55.71)
  Non-assessable 4 (11.43) 8 (22.86) 12 (17.14)
Preoperative eGFR (mL/min/1.73 m2) 95.00±21.92 88.91±24.26 91.96±23.16 0.275
Postoperative eGFR (mL/min/1.73 m2) 90.00±26.55 91.69±21.34 90.84±23.92 0.771
eGFR change (mL/min/1.73 m2) –5.00±19.33 2.77±14.05 –1.11±17.22 0.059
Complications 1 (2.86) 5 (14.29) 6 (8.57) 0.198
 Clavien-Dindo grade I 1 (2.86) 0 1 (1.43) 1.000
 Clavien-Dindo grade II 0 2 (5.71) 2 (2.86) 0.493
 Clavien-Dindo grade III 0 3 (8.57) 3 (4.29) 0.239

Values are presented as mean±standard deviation or number (%).

TRPN, transperitoneal robotic partial nephrectomy; RRPN, retroperitoneal robotic partial nephrectomy; eGFR, estimated glomerular filtration rate.