Authors: (including presenting author): :
Wong HL(1)(2), Chang TP(1)(2), Chun TT (2), Mak MSY(1)(2), Lie HHY(1)(2), Hung WPL(1)(2), Wong TF(1)(2), Tsang CF(1)(2), Lai TCT(1)(2), Na R(2), Ho BSH(2), Ng ATL(1)(2)
Affiliation: :
(1) Division of Urology Department of Surgery, Queen Mary Hospital, Hong Kong, (2) Division of Urology Department of Surgery, The University of Hong Kong, Hong Kong
Keyword 1: :
Robotic surgery
Keyword 2: :
Partial nephrectomy
Keyword 3: :
Renal cell carcinoma
Keyword 4: :
Minimally invasive surgery
Keyword 5: :
Perioperative outcome
Keyword 6: :
Length of Stay
Introduction: :
Kidney cancer, also known as renal cell carcinoma, is a type of cancer that originates in the kidneys. The incidence rate of kidney cancer in Hong Kong varies over time. According to the Hong Kong Cancer Registry, new cases of kidney cancer diagnosed accounting for approximately 3% of all newly diagnosed cancers in Hong Kong. It is one of top ten most common cancers in Hong Kong. Partial nephrectomy (PN) represents the gold standard treatment for T1 renal cell carcinoma (RCC). While robotic-assisted laparoscopic partial nephrectomy (RALPN) has gained widespread adoption globally, comprehensive comparative data with open partial nephrectomy (OPN) in the Hong Kong population remains limited. This study aims to address this gap by comparing the perioperative outcomes of robotic-assisted laparoscopic and open partial nephrectomy for complex renal tumor with moderate to high R.E.N.A.L Score in a Hong Kong tertiary center, providing valuable insights for treatment decision-making in our local population.
Objectives: :
Recent meta-analyses have demonstrated that RALPN provides superior perioperative outcomes compared to open partial nephrectomy, including reduced blood loss, shorter hospital stays, and lower complication rates, while maintaining equivalent oncological control. However, local data on perioperative outcomes of partial nephrectomy in the Hong Kong population remains limited, creating a knowledge gap regarding the applicability of these international findings to our patient demographic. This study aims to compare the perioperative outcomes between robotic-assisted laparoscopic and open partial nephrectomy for moderate to high complex kidney tumor in a Hong Kong tertiary center.
Methodology: :
We retrospectively recruited 42 patients who were diagnosed with stage T1 renal cell carcinoma who underwent partial nephrectomy in a university-based teaching hospital (our institution) between January 2019 and December 2023. We retrieved their basic demographics, relevant surgical parameters (comorbidities, tumor characteristics, and perioperative outcomes) from electronic medical records. The follow up period ranged from 24 to 60 months since operation. Tumor complexity was assessed using the R.E.N.A.L. nephrometry scoring system, that is a standardized tool that quantifies renal tumor complexity based on five anatomical parameters: Radius (tumor size), Exophytic/Endophytic properties, Nearness to collecting system, Anterior/Posterior location, and Location relative to polar Lines. For the scores of 4-6, classified as low and 7-12 classified as moderate to high complexity, respectively. The primary outcome of the study was to evaluate the peri-operative outcomes of robotic vs. open partial nephrectomy for complex renal tumor with moderate to high R.E.N.A.L Score, comparing the operative time, renal warm ischaemic time, estimated blood loss, post-operative length of stay and perioperative complications. The secondary outcomes included the positive surgical margin rate and oncological outcomes. Inclusion criteria comprised all patients who had an preoperative R.E.N.A.L score of 7-12 and undergone partial nephrectomy by either robotic-assisted laparoscopic or open approach and histologically confirmed stage T1 renal cell carcinoma in our institution with follow up in our clinic. Exclusion criteria included emergency operation, previous ipsilateral renal surgery, bilateral renal mass, metastatic disease at presentation and incomplete medical records. For the surgical techniques, in the group of Robotic-Assisted Laparoscopic Partial Nephrectomy (RALPN), all robotic procedures were performed using the Da Vinci Xi Robotic Surgical System (Intuitive Surgical, Sunnyvale, CA). For the open patrial nephrectomy (OPN), the open procedures were performed through standard surgical approaches including subcostal or flank incisions. Hilar control was achieved through vascular clamping, the majority of hilar control were performed with warm ischemic approach followed by tumor excision and renorrhaphy. For the statistical analysis, continuous variables were presented as mean ± standard deviation and compared using Student's t-test. Categorical variables were expressed as frequencies and percentages, with comparisons performed using chi-square or Fisher' s exact tests. A p-value < 0.05 was considered statistically significant. All statistical analyses were performed using SPSS version 28.0 (IBM Corp., Armonk, NY).
Result & Outcome: :
Patient demographics and baseline characteristics A total of 42 patients underwent partial nephrectomy during the study period, with 20 patients (47.6%) in the robotic group and 54 patients (52.4%) in the open group. The two cohorts were well-matched regarding baseline demographics. Mean age was comparable between groups (robotic: 62.9 ± 11.14 years vs. open: 61.23 ± 9.79 years, p = 0.6072). Notably, tumors in the open group were significantly larger than in the robotic group (mean maximal diameter: 3.95 ± 1.35 cm vs. 2.64 ± 0.98 cm, p < 0.001). The R.E.N.A.L scores, which assess tumor complexity, were comparable between groups (robotic: 7.95 ± 0.94 vs. open: 8 ± 0.82, p = 0.8550) Perioperative Outcomes Operative time was similar between groups (robotic: 174.8 ± 43.83 minutes vs. open: 187.68 ± 37.44 minutes, p = 0.3106), as was warm ischemic time (robotic: 19.69 ± 8.93 minutes vs. open: 17.9 ± 9.24 minutes, p = 0.6196). Length of hospital stay showed a clinically significant difference favoring the robotic approach (robotic: 3.5 ± 1.47 days vs. open: 6.55 ± 3.17 days, p < 0.001). Changes in hemoglobin showed statistical significance (robotic: -1.17 ± 1.47 g/dL vs. open: -2.96 ± 1.63 g/dL, p < 0.001), suggesting reduced blood loss with robotic approach. Changes in eGFR at 1-year follow-up (p = 0.1416) showed no significant differences. Readmission rates were similar (robotic: 10% vs. open: 22.7%, p = 0.4897). The transfusion rate was similar in both group (robotic: 10% vs open: 9.1% p= 1). None of the patient requires open conversion in robotic group. Oncological outcome Both group achieved 100% negative surgical margin. In the follow-up period, recurrence rates were 5% and 0% for the robotic and open groups, respectively (p=0.4762). These outcomes are consistent with published literature and reflect the technical adequacy of both approaches for achieving complete tumor excision. Conclusions: Robot-assisted laparoscopic partial nephrectomy (RALPN) provides significant perioperative advantages over open partial nephrectomy (OPN) in patients with moderate to high complexity renal tumors, including reduced postoperative length of hospital stay, decreased intraoperative blood loss, faster postoperative recovery, and improved functional preservation. These benefits support RALPN as an effective and oncologically safe approach for appropriately selected patients with complex renal cell carcinoma.
