Extended lymph node dissection: bladder, kidney

To present recent advances in the field of lymph node dissection (LND) in the context of bladder cancer, upper urinary tract urothelial carcinoma and renal cell carcinoma with focus on dissection extent.

A recent Technetium-based lymph node mapping study has provided several observations to help guide the scientific practice of LND during radical cystectomy. Only 8-10% of primary lymphatic landing sites were located above the uretero-iliac crossing. In contrast, considerable lymph nodes were found in the fossa of Marcille and the internal iliac region. Intraoperative frozen sections are unlikely to abbreviate the LND procedure. Total nodal yield is influenced by numerous factors and may not represent the ideal surrogate for adequacy of LND. The lymphatic drainage of the upper urinary tract is less predictive. For upper urinary tract urothelial cancer, conflicting data question even the staging benefit. In contrast, the results from the sole prospective randomized trial evaluating the value of LND in renal cell carcinoma cannot be generalized because of the limited inclusion of patients with higher stage disease.

In invasive bladder cancer, meticulous extended LND offers both a prognostic and therapeutic benefit. However, the proximal boundaries of the LND template remain undefined. For upper urinary tract urothelial cancer there is a need to define a standardized approach (indication, template) in view of directing patients properly to adjuvant therapies and consecutively evaluate both prognostic and therapeutic value of LND. Similarly, the need for standardization accounts for renal cell carcinoma.