Estimation of the true number of lymph nodes in lymphadenectomy specimens from radical cystectomy

Objective . To evaluate the sensitivity of conventional pathological examination of lymphadenectomy specimens regarding identification of lymph nodes. Material and methods . Fifteen cystectomy specimens with separate package lymphadenectomy specimens from patients with invasive carcinoma of the bladder were subjected to conventional pathological examination followed by paraffin embedding and sectioning of all remaining fatty tissue. Identification of additional lymph nodes missed by the initial investigation was registered. Results . In six of the 15 specimens, additional nodes were identified by sectioning of the fatty tissue. Sensitivity per lymph node of the conventional method was 95% (292 of 308 nodes). One patient with multiple metastatic lymph nodes had one additional positive node. No other additional positive nodes were identified in the specimens. Thus no stage migration was seen. Conclusions . Only a minority of lymph nodes are missed by conventional pathological examination of lymphadenectomy specimens from radical cystectomy. The method is therefore sufficient from a staging perspective.