Location of Retroperitoneal Lymph Node Metastases in Upper Tract Urothelial Carcinoma: Results from a Prospective Lymph Node Mapping Study

Background: There is limited information on the distribution of retroperitoneal lymph node metastases (LNMs) in upper tract urothelial carcinoma (UTUC).Objective: To investigate the location of LNMs in UTUC of the renal pelvis or proximal ureter and short-term complications after radical nephroureterectomy (RNU) with lymph node dissection (LND). Design, setting, and participants: This was a prospective Nordic multicenter study (four university hospitals, two county hospitals). Patients with clinically suspected locally advanced UTUC (stage >T1) and/or clinical lymph node-positive (cN+) dis-ease were invited to participate. Participants underwent RNU and fractionated retroperitoneal LND using predefined side-specific templates. Outcome measurements and statistical analysis: The location of LNMs in the LND specimen and retroperitoneal lymph node recurrences during follow-up was recorded. Postoperative complications within 90 d of surgery were ascertained from patient charts. Descriptive statistics were used.Results and limitations: LNMs were present in the LND specimen in 23/100 patients, and nine of 100 patients experienced a retroperitoneal recurrence. Distribution per side revealed LNMs in the LND specimen in 11/38 (29%) patients with right-sided tumors, for whom the anatomically larger, right-sided template was used, in comparison to 12/62 (19%) patients with left-sided tumors, for whom a more limited template was used. High-grade complications (Clavien grade >= 3) within 90 d of surgery were registered for 13/100 patients. The study is limited in size and not powered to assess survival estimates.Conclusions: The suggested templates that we prospectively applied for right-sided and left-sided LND in patients with advanced UTUC included the majority of LNMs. High-grade complications directly related to the LND part of the surgery were limited.Patient summary: This study describes the location of lymph node metastases in patients with cancer in the upp
Funding Agencies|Swedish Cancer Society [CAN 2020/0709]; Swedish Research Council [2021-00859]; Lund Medical Faculty (ALF); Skane University Hospital Research Funds; Cancer Research Fund at Malmoe General Hospital; Nordic Cancer Union; Skane County Council Research and Development Foundation [REGSKANE-622351]; Goesta Joensson Research Foundation; Foundation of Urological Research (Ove and Carin Carlsson bladder cancer donation); Hillevi Fries Research Foundation