Extent of Pelvic Lymph Node Dissection During Radical Cystectomy: Where and Why!

Abstract

In their classic article on radical cystectomy published in 1962 [1], Whitmore and Marshall described the standard template for a bilateral pelvic lymph node dissection (PLND). PLND is begun along the lateral margin of the common iliac artery, where the ureter crosses the vessel, and continues distally to Cooper’s ligament, removing all areolar tissue, fat, and nodes lateral, above, and below the common and external iliac artery and vein. The obturator nodes are removed from the pelvic sidewall and obturator fossa, completely resecting the obturator artery and vein at their origin from the hypogastric artery to flush with the obturator foramen. The posterior pelvic wall is neatly dissected of nodal tissue, exposing the internal iliac vessels and their ramifications, and extended up to remove the presacral nodes. It is important to remove all nodes medial and lateral to the hypogastric vessels, including underneath the common iliac vessels at their bifurcation.When nodes are left behind, this location is a common site of pelvic recurrence. The deep dissection exposes the fascia over the sciatic nerve and removes fat and adjacent lymphatics from the ischiorectal fossa, visual landmarks confirming a complete hypogastric dissection. A standard PLND has the following limits: proximal, midportion of the common iliac artery; lateral, genitofemoral nerve; medial, bladder wall; distal, inguinal ligament; and inferior, pelvic floor and hypogastric vessels, lying on the deep muscular and bony walls of the pelvis. This is considered the standard PLND performed during radical cystectomy. Anything less is a limited dissection; anything more (up to bifurcation of aorta and above) can be called an extended PLND. The rationale for PLND during cystectomy is improved staging and even cure in a select minority of patients with