Effects of extended lymphadenectomy and postoperative chemotherapy on node-negative gastric cancer.

Aim: To investigate the effects of extended lymphadenectomy and postoperative chemotherapy on gastric cancer without lymph node metastasis.

Methods: Clinical data of 311 node-negative gastric cancer patients who underwent potentially curative gastrectomy with more than 15 lymph nodes resected, from January 2002 to December 2006, were analyzed retrospectively. Patients with pT4 stage or distant metastasis were excluded. We analyzed the relationship between the D2 lymphadenectomy and the 5-year survival rate among different subgroups stratified by clinical features, such as age, tumor size, tumor location and depth of invasion. At the same time, the relationship between postoperative chemotherapy and the 5-year survival rate among different subgroups were also analyzed.

Results: The overall 5-year survival rate of the entire cohort was 63.7%. The 5-year survival rate was poor in those patients who were: (1) more than 65 years old; (2) with tumor size larger than 4 cm; (3) with tumor located in the upper portion of the stomach; and (4) with pT3 tumor. The survival rate was improved significantly by extended lymphadenectomy only in patients with pT3 tumor (P = 0.019), but not in other subgroups. Moreover, there was no significant difference in survival rate between patients with and without postoperative chemotherapy among all of the subgroups (P > 0.05).

Conclusion: For gastric cancer patients without lymph node metastasis, extended lymphadenectomy could improve the survival rate of those who have pT3-stage tumor. However, there was no evidence of a survival benefit from postoperative chemotherapy alone.