Perioperative, functional, and oncologic outcomes in obese patients undergoing Da Vinci robot-assisted radical prostatectomy: a systematic review and meta-analysis

OBJECTIVE: The influence of robot-assisted radical prostatectomy (RARP) in obese (OB) and non-obese (NOB) prostate cancer patients remains a topic of debate. The objective of this study was to juxtapose the perioperative, functional, and oncologic outcomes of RARP in OB and NOB cohorts. MATERIALS AND METHODS: We systematically searched the databases such as PubMed, Embase, Web of Science, and the Cochrane Library database to identify relevant studies published in English up to September 2023. Review Manager was used to compare various parameters. The study was registered with PROSPERO (CRD42023473136). Sixteen comparative trials were included for 8434 obese patients compared with 55,266 non-obese patients. RESULTS: The OB group had a longer operative time (WMD 17.8 min, 95% CI 9.7,25.8; p < 0.0001), a longer length of hospital stay (WMD 0.18 day, 95% CI 0.12,0.24; p < 0.00001, a higher estimated blood loss (WMD 50.6 ml, 95% CI 11.7,89.6; p = 0.01), and higher pelvic lymphadenectomy rate (RR 1.08, 95% CI 1.04,1.12; p < 0.0001)and lower nerve sparing rate (RR 0.95, 95% CI 0.91,0.99; p < 0.01), but there was no difference between unilateral (RR 1.0, 95% CI 0.8,1.3; p = 0.8)and bilateral (RR 0.9, 95% CI 0.9,1.0; p = 0.06)nerve sparing rate. Then, complication rates (RR 1.6, 95% CI 1.5,1.7; p < 0.00001) were higher in the OB group, and both major (RR 1.4, 95% CI 1.1,1.8; p = 0.01)and minor (RR 1.4, 95% CI 1.1,1.7; p < 0.01)complication rates were higher in the OB group. Moreover, obese patients showed significantly higher probabilities of incontinence (RR 1.17, 95% CI 1.03,1.33; p = 0.01) and impotency (RR 1.08, 95% CI 1.01,1.15; p = 0.02) at 1 year. Last, the positive surgical margin (RR 1.2, 95% CI 1.1,1.3; p < 0.01) was higher in the OB group. CONCLUSION: In the obese group, perioperative outcomes, total complications, functional outcomes, and oncologic outcomes were all worse for RARP. Weight loss before RARP may be a feasible strategy to improve the prognosis of patients.