Lymph node mapping in patients with bladder cancer undergoing radical cystectomy and lymph node dissection to the level of the inferior mesenteric artery

OBJECTIVE: To evaluate extended lymph node dissection (LND) as a nodal staging tool in the treatment of invasive carcinoma of the urinary bladder and to suggest a reasonable proximal limit of the dissection. PATIENTS AND METHODS: In all, 170 patients underwent radical cystectomy with extended LND up to the level of the inferior mesenteric artery. Specimens were evaluated as 13 separate packages from pre-designated anatomical locations. The number of LNs and presence of positive LNs (LN+) at each location was prospectively registered. RESULTS: The median (range) number of LNs removed was 24 (6-62). In all, 25.3% of the patients had LN+. The median (range) number of LN+ was 2 (1-20). Advanced T-stage was correlated with a higher risk of LN+ but not to the specific location of the LN+. Two patients had LN+ above the common iliac bifurcation with no LN+ more distally located within the pelvic region. All other patients with LN+ above the common iliac bifurcation had more distally located LN+. There were no skip lesions to LNs above the aortic bifurcation. CONCLUSIONS: Extended LND above the common iliac bifurcation including the presacral area provides a more accurate LN staging compared with a standard pelvic LND. Extending the limits above the aortic bifurcation is not necessary from a staging perspective.