OBJECTIVETo investigate the micrometastatic characteristics in the gastric cancer patients with negative lymph node invasion by routine pathological examination and evaluate the relationship between micrometastasis and clinicopathological features.

METHODSOne hundred and thirty-eight lymph nodes from No. 7 group in 46 patients with node-negative gastric cancer by routine examination were examined by consecutive sections. Telomerase activity was determined by RT-PCR and ELISA. Clinicopathological data were analyzed by statistical method.

RESULTSMicrometastasis was found in 32 lymph nodes (23.2%) from 13 cases (28.3%) by consecutive sections. Telomerase activity was positive in 49 lymph nodes (35.5%) from 20 cases (43.5%). The sensitivity, specificity, positive and negative predictive value and diagnostic accuracy of TRAP-ELISA was 100%, 84%, 65%, 100% and 88% respectively. The micrometastasis in lymph node was correlated with age, sex, primary tumor location, histological classification and metastatic lymph node type (P> 0.05), but correlated with the gross type of the primary tumor, size and serosa invasion (P< 0.05).

CONCLUSIONSIt is necessary to discern the micrometastasis in gastric cancer with negative lymph node by routine examination in order to objectively evaluate the clinicopathological classification and prognosis. TRAP-ELISA can be a complementary method to traditional histological examination.