Impact on survival of the number of lymph nodes removed in patients with node-negative gastric cancer submitted to extended lymph node dissection

Purpose

This study was designed to establish whether the number of lymph nodes removed has an effect on prognosis in patients with node-negative gastric cancer.

Patients and Methods

We retrospectively analysed data of 114 consecutive patients who underwent gastrectomy and extended lymph node dissection for node-negative adenocarcinoma of the stomach between 2000 and 2005. Standard survival methods and restricted cubic spline multivariable Cox regression models were applied.

Results

Median age was 63 years and 67 patients out of 114 (59%) were males. Median number of dissected LNs was 22 (range 2-73). Median follow-up was 76 months. Patients who had ≤15 nodes removed had significantly worse distant disease-free survival, disease-free survival and overall survival at multivariable analysis than other patients. The results did not change when pT1 and pT2-3 cancer patients were analysed separately. The risk of distant metastases decreased as the number of dissected lymph nodes increased (>15).

Conclusions

More extended lymph node resection offered survival benefit even in the subgroup of patients with early stage disease. Lymphadenectomy involving more than 15 lymph nodes should be performed for the treatment of node-negative gastric cancer.

Synopsis

The impact on survival of the number of lymph nodes removed in patients with node-negative gastric cancer has not been established. This study suggests that more extended lymph node resection offers protection, as patients who had ≤15 nodes removed had significantly worse disease-free survival and overall survival at multivariate analysis than patients in whom >15 nodes were removed.