Many studies favor an extended lymphadenectomy at the time of a potentially curative gastrectomy for node-positive gastric cancer, and the risk of long-term death tends to decrease when the number of resected lymph nodes increases to about 25. However, few studies have assessed the relative contribution of the total number of resected lymph nodes to the outcome of patients with node-negative gastric cancer. Further studies are needed to know how the numbers of dissected LNs may affect the survival outcome of patients with node-negative gastric cancer.
A research article to be published on August 21, 2009 in the World Journal of Gastroenterology addresses this question. This study was performed by a team led by Professor Chang-Ming Huang from Department of Oncology, Affiliated Union Hospital of Fujian Medical University. Two hundred and eleven patients with node-negative gastric cancer who underwent D2 curative resection were analyzed retrospectively. This article went ahead to investigate the effect of the number of lymph nodes resected in a large population of patients with node-negative gastric cancer.
The number of dissected LNs emerges as one of the most important prognostic indicators. Patients with comparable depth of invasion had a better survival as the number of resected LNs increased. The patients had better long-term survival outcomes with LN counts of > 15 for pT1-2, > 20 for pT3-4, and > 15 for the entire cohort. There was a statistically significant, negative correlation between the number of resected LNs and the recurrence rate. The study also found that the number of dissected LNs was not significantly correlated with the post-operative complication rate.
Based on their results, the authors suggest that a large number of dissected lymph nodes in the procedure of D2 dissection is recommended, in order to improve the long-term survival and reduce the recurrence rate of patients with node-negative gastric cancer. Suitable increments of the number of dissected LNs would not increase the post-operative complication rate. Therefore, this is an interesting and well-done study investigating the long-term effect of the number of resected lymph nodes on the prognosis of patients with node-negative gastric cancer.