428 Comparison of peri-operative outcomes of robotic partial nephrectomy and laparoscopic partialnephrectomy in surgical treatment of small renal masses

Eur Urol Suppl 2014;13;e428 Print!

Zargar H.1, Ball M.W.2, Allaf M.E.2, Larson J.3, Marshall S.4, Kumar R.5, Stifelman M.D.4, Bhayani S.B.3, Rogers C.G.5, Kaouk J.H.K.1

1Glickman Urological Institute, Cleveland Clinic, Cleveland, United States of America, 2James Buchanan Brady Uroloogical Institute, The

Johns Hopkins Medical Institutions, Baltimore, United States of America, 3Washington University School of Medicine, Dept. of Urology, St.

Louis, United States of America, 4New York University School of Medicine, Dept. of Urology, New York, United States of America, 5Vattikuti

Urology Institute, Henry Ford Health System, Detroit, United States of America

INTRODUCTION & OBJECTIVES: Partial nephrectomy is the treatment of choice for treatment of small renal neoplasm. For small renal

masses robotic nephron sparing surgery achieves similar results as open technique with addition of being minimally invasive. The trifecta of

oncology, complication and functional outcome has been proposed as a measure of effectiveness of this approach.

MATERIAL & METHODS: We retrospectively reviewed records of 1542 cases of RPN and 903 cases of LPN performed in 5 high volume

centres across USA from 2000 to mid 2013. We limited our study to PN for small renal masses (≤ 4 cm). Tumour complexity was assigned

according to R.E.N.A.L nephrometry score (RNS). Based on RNS value, tumours were divided into simple (4-6), intermediate (7-9) and

complex (10-12) groups. We defined the Trifecta of negative surgical margin, no perioperative complications and warm ischemia of less

than 25 minutes, as a surrogate of ideal short-term surgical outcome. The primary endpoint of the study was to compare the rate of Trifecta

between LPN and RPN.

RESULTS: Total 1842 patients (1185 RPN and 657 LPN) met our inclusion criteria (tumour ≤ 4 cm). Patients in the RPN group were older

(59.3 vs. 57.6 p=0.003) and had higher mean Charlson Comorbidity Index (2.21 vs. 1.32 p<0.001). Higher proportions of the tumours in the

RPN cohort were intermediate or complex (55.2% vs. 35.9% p<0.001). The RPN group had lower warm ischemia (19.2 vs. 26.7 minutes)

time, overall complication rate (14.9 vs. 22.1%, p <0.001), and positive margin rate (3.3% vs. 9.6%, p <0.001). A significantly higher Trifecta

rate was observed for RPN (70.7% vs. 32.4%, p<0.001). On multivariable analysis RPN, RNS and tumor size were predictors of achieving

Trifecta.

Table 1.Multivariable analysis of factors predicting trifecta

Variable OR (95% CI) p

Age .994 (.982-1.006) .310

BMI 1.001(.996-1.006) .607

CCI <5CCI>=5

1.467(.266-.818)

.008

Tumor Size .808(.735-.888) .000

RNS RNS(4-6)RNS(7-9)RNS(10-12)

11.006(.752-1.345).518(.326-.824)

.01 .970.005

LPNRPN

15.924(3.774-9.298)

.000

CONCLUSIONS: In this large multi-intuitional comparative series, we have demonstrated that RPN is superior to LPN in achieving the

Trifecta, despite the presence of more complex tumours in the robotic cohort. Although the Trifecta does not encompass the long-term

functional outcome of nephron sparing surgery, it provides us with an immediate surrogate for surgical quality control. Our results

demonstrate that the robotic platform allows the surgeon to perform minimally invasive complex surgery more efficiently.