Super extended versus extended pelvic lymph node dissection in patients undergoing radical cystectomy for bladder cancer: a comparative study

Purpose: There is evidence from retrospective studies that radical cystectomy with extended pelvic lymph node dissection provides better staging and outcomes than limited lymph node dissection. However, the optimal limits of extended lymph node dissection remain unclear. We compared oncological outcomes at 2 cystectomy centers where 2 different extended lymph node dissection templates are practiced to determine whether removing lymphatic tissue up to the inferior mesenteric artery confers an additional survival advantage.

Materials and methods: Patients undergoing radical cystectomy and extended lymph node dissection with curative intent from 1985 to 2005 were included in analysis if they met certain criteria, including clinically organ confined urothelial bladder carcinoma (cN0M0), pathological stage pT2-pT3, negative surgical margins and no neoadjuvant therapy. Survival and recurrence data were analyzed.

Results: Demographic data and pathological subgroup distribution (pT2 and pT3) were similar in the 554 University of Southern California and 405 University of Bern patients. University of Southern California patients had higher median number of lymph nodes removed than University of Bern patients (38 vs 22, p <0.0001) and a higher incidence of lymph node metastasis (35% vs 28%, p = 0.02). However, the University of Southern California and University of Bern groups had similar 5-year recurrence-free survival for pT2pN0-2 (57% vs 67%) and pT3pN0-2 (32% vs 34%) disease (p = 0.55 and 0.44, respectively). The overall recurrence rate was equal at the 2 institutions (38%).

Conclusions: Meticulous extended lymph node dissection up to the mid-upper third of the common iliac vessels appears to provide survival and recurrence outcomes similar to those of a super extended template up to the inferior mesenteric artery. Complete skeletonization in the extended lymph node dissection template is more important than nodal yield. This does not exclude the possibility that certain patient subgroups with suspicious nodes or after neoadjuvant chemotherapy may benefit from more extensive lymph node dissection.