Lymphadenectomy in bladder cancer: how high is "high enough"?

PURPOSE: The role of a regional lymphadenectomy in the surgical treatment of high-grade, invasive transitional cell carcinoma of the bladder has evolved over the last several decades. Although the application of a lymphadenectomy for bladder cancer is not significantly debated, the absolute extent or level of proximal dissection of the lymphadenectomy remains a controversial issue.
MATERIAL AND METHODS: A review of the literature should help elucidate the rationale and extent of an appropriate lymphadenectomy in patients undergoing radical cystectomy for bladder cancer. Various surgical issues of lymphadenectomy as well as prognostic factors in patients undergoing radical cystectomy for bladder cancer are examined.
RESULTS: A growing body of evidence, spanning from early autopsy and cadaveric studies to recent retrospective series and multicenter prospective trials, suggests that an extended lymph node dissection (cephalad extent to include the common iliac arteries) may provide not only prognostic information but also provide a therapeutic benefit for both patients with lymph node-positive and lymph node-negative disease undergoing radical cystectomy for bladder cancer. Although the absolute boundaries of the lymphadenectomy remain a subject of controversy, historical reports confirmed by recent lymphatic mapping studies suggest the inclusion of the common iliac as well as possibly presacral nodes in the routine lymphadenectomy for transitional cell carcinoma of the bladder. The need to extend the dissection higher to include the distal para-aortic and paracaval lymph nodes may be important in select individuals but remains more controversial. The extent of the primary bladder tumor (p-stage), number of lymph nodes removed, the lymph node tumor burden (tumor volume), and lymph node density (number of lymph nodes involved/number of lymph nodes removed) are all important prognostic variables in patients undergoing cystectomy with pathologic evidence of lymph node metastases. Systemic adjuvant chemotherapy remains a mainstay of treatment of patients with lymph node metastases.
CONCLUSIONS: Radical cystectomy with an appropriately performed lymphadenectomy provides the best survival outcomes and lowest local recurrence rates. Although the absolute limits of the lymph node dissection remain to be determined, evidence supports a more extended lymphadenectomy to include the common iliac vessels and presacral lymph nodes at cystectomy in patients who are appropriate surgical candidates. When feasible, adjuvant chemotherapy is warranted in patients with positive nodal metastasis.