16 - Para-aortic nodes

Station number 16 (para-aortic nodes) includes four separate groups of lymph nodes around the abdominal aorta and inferior vena cava:

• The aortic hiatus nodes (16a1) are located around the diaphragmatic aortic hiatus, over the anterior side of the aorta, from the inferior hedge of the hiatus to the upper border of the coeliac artery.

• The superior paraortic lymph nodes (16a2) are located over the anterior surface of the aorta, from the coeliac artery to the lower border of the left renal vein.

• The middle paraaortic nodes (16b1) are located around the anterior surface of the aorta and vena cava, from the lower border of the left renal vein to the upper border of the origin of the inferior mesenteric artery; right and left border are defined by the right border of the inferior vena cava and by the left gonadic vessels.

• The inferior paraaortic nodes (16b2) are located around the anterior surface of the aorta and vena cava, between the upper border of the origin of the inferior mesenteric artery and the aortic bifurcation.