Login to Access Video or Poster Abstract: MP20-16
Sources of Funding: none

Introduction

A 2008 mapping study showed that primary lymphatic landing sites of the prostate are also found medially to the internal iliac vessels, in the fossa of Marcille and along the common iliac vessels up to the ureter crossing. We then expanded our PLND template accordingly (Graphic). We assessed the effects of the template revision on pathologic and complication outcomes.

Methods

753 pts underwent RP and extended PLND from 2000 to 2008 (485 pts [64%]; historical cohort) and from 2010 to 2015 (268 [36%]; contemporary cohort) at a referral center. Descriptive statistics and a logistic regression model were used. Subanalysis of patients with ?2 metastases was performed because these patients are the ones who may most benefit from removal of LN metastases.

Results

Median number of LN removed in the historical cohort was 25 (IQR 19-33) and in the contemporary cohort 34 (27-43; p <0.0001). _x000D_ Among 80 N+ pts (16%) in the historical cohort, the sole location of metastasis was external iliac/obturator region in 23/80 (29%) and internal iliac in 18/80 (23%), while 39/80 (49%) had metastases in both locations. Among 72 N+ pts (27%) in the contemporary cohort, the sole location of metastasis was external iliac/obturator region in 17 (24%) patients, internal iliac region in 24 (33%), and common iliac region in 1 (1%), while 30 (42%) had metastases in more than one location. While 5 patients had LN metastases in the fossa of Marcille, the latter was never the exclusive location. However, among pts with ?2 metastases in the contemporary cohort, 3 pts had one or both metastases in the common iliac regions or in the fossa of Marcille only. _x000D_ The adjusted risk to harbor nodal metastases was higher in the contemporary cohort, albeit not significantly (OR 1.19, 95% CI 0.77-1.84; p=0.4). Complications such as lymphoceles, thrombosis and neuropraxia were no more frequent with a more extended template. _x000D_

Conclusions

A more extended PLND template detects LN metastases in the common iliac regions and in the fossa of Marcille and is associated with an overall non-significant higher risk of harboring LN metastases.

Funding

none