Is 3D laparoscopic off clamp simple enucleation a feasible alternative for clinical T1 renal tumors? Outcomes from a single center experience.

Purpose: To evaluate the safety of 3D laparoscopic off clamp simple enucleation (SE) of kidney tumors versus standard laparoscopic on-clamp partial nephrectomy (PN) in terms of perioperative, oncological and functional outcomes.

Methods: All patients that underwent 3D laparoscopic nephron sparing surgery (NSS) in our department for clinical T1 tumors between January 2019-September 2020 were included. Of the total of 84 patients, 38 (45.24%) underwent SE (SE group) and 46 (54.76%) PN (PN group). Perioperative data was collected and analyzed. Oncological outcomes were evaluated by the positive surgical margin (PSM) rate and follow-up at 6 months after surgery.

Results: Mean age, gender, tumor size, PADUA score and length of hospital stay were comparable between the two groups. Estimated intraoperative blood loss (284.21 ml vs 151.52 ml, p=0.0001) and hemoglobin drop (p=0.0001) were significantly lower for the PN group. Patients that underwent SE showed a better preservation of renal function (eGFR drop of 4.4 ml/min vs 1.78 ml/min, p=0.75). No significant differences were found regarding the PSM, although the PSM rate was lower in the SE group when compared with the PN group (2.63% vs 4.34%, p= 0.07).

Conclusion: Off-clamp simple enucleation of renal masses is feasible by laparoscopic approach and has produced comparable oncologic outcomes with standard on-clamp partial nephrectomy, with an incremental advantage for the preservation of renal function.