The role of lymphadenectomy in high-grade invasive bladder cancer.

Radical cystectomy with bilateral pelvic iliac lymphadenectomy is a standard treatment for high-grade, invasive bladder cancer. Cystectomy arguably provides the best survival outcomes and the lowest local recurrence rates. Although the extent or absolute limits of the lymph node dissection are unknown and remain to be better defined, an ever-growing body of data supports a more extended lymphadenectomy at the time of cystectomy in all patients who are appropriate surgical candidates. An extended lymph node dissection should include the distal para-aortic and paracaval lymph nodes as well as the pre-sacral nodes, known anatomic sites of lymph node drainage from the bladder and potential sites of lymph node metastases in patients with bladder cancer. An extended dissection may provide a survival advantage in patients with node-positive and node-negative tumors without significantly increasing the morbidity or mortality of the surgery. The extent of the primary bladder tumor (p stage), the number of lymph nodes removed, and the lymph node tumor burden are important prognostic variables in patients undergoing cystectomy with pathologic evidence of lymph node metastases. Lymph node density may become an even more useful prognostic variable in these high-risk, node-positive patients with bladder cancer. This concept simultaneously incorporates the lymph node tumor burden (number of lymph nodes involved) and the number of lymph nodes removed (extent of the lymphadenectomy), improving the stratification of lymph node-positive patients following radical cystectomy. This notion may also be useful in future staging systems. Adjuvant therapies and clinical trials should consider applying these concepts, because they may help reduce bias and incorporate the extent of the lymphadenectomy, which currently is not standardized.