Objective:Nephron-sparing surgery (NSS) for small renal masses offers a similar functional and oncological outcome to that of radical surgery.Laparoendoscopic single-site surgery(LESS) emerges as an advanced altative for reduced invasiveness and improves cosmesis; LESS is developing quickly and its indications have been expanded,but still in its infancy.The aim of this paper is to report our preliminary experience in transumbilical LESS partial nephrectomy (LESS-PN),so as to assess its utility,safety and efficacy.Methods:From August 2009 to October 2010,3 patients underwent transumbilical LESS-PN via a novel multi-channel TriPort by a single experienced urologist in our institution.Patient demographics,perioperative and follow-up data were prospectively collected and analyzed.Results:All the three procedures were successfully completed.A 5-mm ancillary trocar was utilized in all 3 cases. The mean operative duration was 226.3 (210-254 min) with an estimated blood loss of 56.7 ml (20-100 ml).Mean warm ischemia time was 35.7 min (19-48 min). One patient was transfused due to postoperative bleeding.The recovery was uneventful and mean length of postoperative stay was 13 days (12-14 days).At the latest follow-up,all patients remained symptom-free and had normal renal function without evidence of recurrence,and they were delighted for a hidden transumbilical scar.Conclusion:Transumbilical LESS-PN is a feasible and safe procedure albeit extremely technically challenging.Surgical outcomes at a median follow-up of 2 years are promising,while currently it should be reserved for highly selected patients with favorable tumor anatomy and performed by a very experienced laparoscopic surgeon.