Effect of obesity and overweight status on complications and survival after minimally invasive kidney surgery in patients with clinical t2 renal masses.

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Journal of endourology / Endourological Society


OBJECTIVE: To evaluate the effect of obesity and overweight on surgical, functional and survival outcomes in patients with large kidney masses after minimally invasive surgery (MIS).

MATERIAL AND METHODS: Within a multi-center, multi-national dataset, patients diagnosed with a ≥cT2 renal mass and treated with minimally invasive (laparoscopic or robotic) kidney surgery (radical or partial nephrectomy) during the period 2003-2017 were abstracted. They were stratified according to the body mass index (BMI) classes as normal-weight (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2) and obese (≥30.0 kg/m2). Mixed models and Cox proportional hazard regression tested differences in complication rates, eGFR change over time, overall mortality (OM) and disease recurrence (DR) rates.

RESULTS: Of 812 patients, 30.6% were normal-weight, 42.7% were overweight and 26.8% obese. Overweight (OR 0.82, 95% CI: 0.51-1.51, p=0.406) and obese patients (0.81, 95% CI: 0.44-1.47, p=0.490) experienced similar complication rates than normal weight. Moreover, no statistically significant differences in eGFR were found for overweight (p=0.129) or obese (p=0.166) patients compared to normal-weight. However, higher OM rates were recorded in overweight (HR 3.59, 95%CI: 1.03-12.51, p=0.044) as well as in obese patients (HR 7.83, 95%CI: 2.20-27.83, p=0.002). Similarly, higher DR rates were recorded in obese (HR 2.76, 95%CI: 1.40-5.44, p=0.002).

CONCLUSIONS: Obese and overweight patients do not experience higher complication rates or worse eGFR after minimally invasive kidney surgery, which therefore can be deemed feasible and safe also in these subset of patients. Nevertheless, obese and overweight patients seem to carry a higher risk of OM, and therefore they should undergo a strict follow-up after surgery.

Clinical Institute

Digestive Health

Clinical Institute

Kidney & Diabetes