Lymph node dissection for bladder cancer: Current standards and the latest evidence

Abstract

Lymph node dissection is an indispensable component of radical cystectomy for bladder cancer. Information obtained with lymph node dissection is highly predictive of patient survival, affecting decision‐making for adjuvant therapy (diagnostic role). Also, lymph node dissection provides survival benefits in certain patients by removing metastasized nodes (therapeutic role). However, an optimal extent of lymph node dissection has not been established yet. Data from surgical mapping studies showed that approximately 10% of the primary lymphatic landing sites were common iliac nodes, suggesting that lymph node dissection below the common iliac bifurcation is suboptimal. Several retrospective studies have shown a possible survival advantage with more extended lymph node dissection. However, the results of the first prospective randomized controlled trial failed to prove the survival advantage of extended lymph node dissection up to the level of the inferior mesenteric artery, compared with lymph node dissection below the bifurcation of the common iliac artery. Currently, lymph node dissection templates recommended by major guidelines are not consistent with each other. Furthermore, the evidence is limited in the settings of neoadjuvant chemotherapy, robot‐assisted surgery and high‐risk non‐muscle‐invasive disease. Physicians need to decide the extent of lymph node dissection for each patient, taking into account the potential survival benefit and possible harms of extended lymph node dissection. Another randomized controlled trial is currently underway and will provide further evidence shortly.

Editorial Comment to Lymph node dissection for bladder cancer: Current standards and the latest evidence

“…In this trial, extended LND failed to show survival advantages over limited LND in patients undergoing RC. As stated in the present article, 10–20% of primary LNs of bladder cancer are located in the common‐iliac/presacral regions, suggesting that LND below the bifurcation of the common iliac artery might be suboptimal 1 . Another randomized study (SWOG‐1011) is ongoing, which will provide further knowledge regarding optimal templates of LND.…”

“…As for cN0 bladder cancer patients, current guidelines recommend neoadjuvant chemotherapy before RC. Importantly, as highlighted in this review article, there has been no clear evidence showing survival benefits of LND after neoadjuvant chemotherapy 1 . Further studies are required to determine the impact of LND on patient survival in this setting.…”

“…The present article also summarized previous studies addressing the optimal extent of LND, which has not been established to date 1 . Although some thought leaders have explored the potential benefit of extended/super‐extended LND, discouraging results in the first randomized trial recently published that compared extended versus limited LND made the pendulum swing back 4 .…”

“…In this article, Nakagawa reviewed the latest evidence of LND for bladder cancer and discussed the controversies 1 . Pathological lymph node (LN) metastasis is an established prognostic factor for bladder cancer patients.…”

Imaging and Management of Bladder Cancer

“…A trend towards increased recurrence free survival, cancer free survival, and overall survival was observed which did not reach statistical significance. In the extended lymph node dissection arm, 4 patients out of the 44 pN+ patients had skip metastases in the common iliac or presacral nodes, and the patients would have been diagnosed as pN0 had they not undergone extended lymph node dissection [65,66]. Another trial evaluating extended versus standard lymph node dissection, SWOG S1011, is ongoing with a few notable differ-ences from the LEA trial.…”