To address the incidence and potential risk factors of port site metastasis (PSM) in patients who underwent laparoscopic radical nephroureterectomy (RNU) for upper tract urothelial carcinoma.

Between January 2013 and December 2018 laparoscopic RNU were performed in 240 patients at our institution, including 145 with renal pelvic tumor and 135 with ureteral tumor (40 patients have both tumor). Laparoscopies were performed through the transperitoneal approach in 28 patients, and retroperitoneal in 212 patients. Clinical data are retrospectively collected.

Perioperative and pathologic data are available in all 240 cases. After a mean follow-up of 12.6 months (range 3-45 months), 4 patients (1.7%) developed PSM following retroperitoneal RNU at an average of 4.3 months. Tumor stage is T2N0M0 in one, T3N0M0 in two, and T3N1M0 in one, respectively. Tumor grade are high-grade urothelial carcinoma in all. The incidence of PSM is 2.8% (4/145) and 0.7% (1/135) in renal pelvic and ureteral tumor, respectively.

We report a 1.7% incidence of PSM in upper tract urothelial carcinoma after laparoscopic RNU. We suggest that air leakage during retroperitoneal approach, high tumor stage (pT3) and grade, and advanced renal pelvic tumor with micrometastases could increase the potential risks of PSM.