Removal of at least 29 lymph nodes tied to better survival in advanced gastric cancer

Last Updated: 2017-01-10

By Reuters Staff

NEW YORK (Reuters Health) - Lymphadenectomy that includes at least 29 lymph nodes is associated with improved survival in patients with advanced gastric cancer, according to a large international study.

D2 lymphadenectomy allows for clearance of lymph nodes most likely to harbor metastatic disease, researchers note in the Journal of the American College of Surgeons, online December 22.

An increased number of nodes for evaluation is now internationally accepted as the standard procedure for patients undergoing curative surgical resection of gastric cancer, they add.

Adequate nodal dissection for D2 lymphadenectomy would yield at least 33 to 47 lymph nodes, according to several clinical trials, but the optimal number remains to be determined, write Dr. Woo Jin Hyung from Yonsei University College of Medicine in Seoul, Korea, and colleagues.

To investigate, the team analyzed data on more than than 25,000 patients from the largest combined international data set created to date - a combination of the U.S. Surveillance, Epidemiology, and End Results (SEER) database and data from Yonsei University.

Based on a Joinpoint model, using both mean and median survival, the optimal number of lymph nodes to be retrieved is 29, the researchers found.

Survival was significantly improved for all stages of gastric cancer when comparing patients having 29 or more lymph nodes removed with patients having fewer nodes removed.

"The lymph node count of 29 is almost two-fold that of the 15 lymph node minimum currently recommended by the National Comprehensive Cancer Network (NCCN) guidelines and 13 lymph nodes more than the 16 lymph nodes considered adequate for proper staging by the American Joint Committee on Cancer (AJCC)," the researchers note.

"Based on our results and supported by current literature, we recommend an extended lymphadenectomy with a new goal of 29 lymph nodes retrieved for evaluation," they conclude. "A properly performed D2 lymphadenectomy is expected to yield greater than 29 lymph nodes and should be recommended."

"While changing of guidelines to include a cutoff of 29 lymph nodes will take time to implement and become fully accepted, the data on stage migration can still be applied," the authors say. "Patients who received inadequate lymphadenectomy could be identified and be considered in the next stage for consideration of adjuvant therapies."

Dr. Hyung did not respond to a request for comments.

SOURCE: http://bit.ly/2iXFFKS

J Am Coll Surg 2016.