Radical cystectomy with super-extended lymphadenectomy: impact of separate vs en bloc lymph node submission on analysis and outcomes.

Abstract

To update our previous analysis of the clinical and pathological impact of the change in the submission of lymphadenectomy specimens from en bloc to 13 separate anatomically defined packets, which took place at the University of Southern California in May 2002, and to determine whether lymph node (LN) packeting resulted in any change in oncological outcomes. A total of 846 patients who underwent radical cystectomy (RC) with super-extended LN dissection for cTxN0M0 bladder cancer between January 1996 and December 2007 were identified. Specimens of 376 patients were sent en bloc (group 1), and specimens of 470 patients were sent in 13 separate anatomical packets (group 2). The pathological tumour stage distribution and the proportion of LN-positive patients (group 1: 82 patients [22%] versus group 2: 99 patients [21%]; P = 0.80) were similar between the two groups: the median [range] number of total LNs identified increased significantly (group 1: 32 [10-97] versus group 2: 65 [10-179]; P < 0.001). LN density decreased (group 1, 11% versus group 2, 4%; P = 0.005). The median [range] number of positive LNs removed was similar (group 1: 0 [0-30] versus group 2: 0 [0-97]; P = 0.87). No nodal stage shift was observed. The 5-year overall survival (group 1: 58% versus group 2: 59%; P = 0.65) and recurrence-free survival rates (group 1: 68% versus group 2: 70%; P = 0.57) were similar. The incidence of patients with positive LNs remained unchanged, regardless of how the LN specimen was submitted. Submitting 13 separate nodal packets significantly increased the total LN yield, but did not result in a significant increase in the number of positive LNs or a consecutive nodal stage shift and did not affect oncological outcomes. Based on these results LN density is not an accurate prognosticator.