OBJECTIVETo investigate the clinicopathological and biological features of micrometastasis in early gastric cancers.

METHODSEleven cases of early gastric cancer with micrometastasis (micrometastatic, MM group) and 46 cases of early gastric cancer with lymph node metastasis (control group) were included in the study. Immunochemical staining of ssDNA, bcl-2, p53, E-cadherin, Ki-67, CD34 was performed. The superficial lesions, invasive fronts and lymph nodes were examined in both groups.

RESULTSPositive rate of ssDNA at the superficial lesions in MM group was higher than that in control group. In MM group the positive rate of ssDNA in micrometastasis was higher than that at invasive fronts and in lymph nodes. Positive rate of bcl-2 at the superficial lesions in micrometastasis was higher than that at invasive fronts and lymph nodes. Positive rate of c-myc at the superficial lesions in MM group was higher than that in control group. Positive rate of E-cadherin and the percentage of microvascular areas at the lymph nodes in MM group was lower than those in control group. Proliferative ability of cancer cells at superficial lesions and lymph nodes in MM group was lower than those in control group. Lymph nodes <3 mm in micrometastasis accounted for 27.3%.

CONCLUSIONThe pathological and biological features of micrometastasis in early gastric cancer show low positive rate of ssDNA, E-cadherin, Ki-67 and low percentage of microvascular areas at the lymph nodes.

Adenocarcinoma ; metabolism ; pathology ; Antigens, CD34 ; analysis ; Biomarkers, Tumor ; analysis ; Cadherins ; analysis ; DNA, Single-Stranded ; analysis ; Female ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; analysis ; Lymphatic Metastasis ; Male ; Middle Aged ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Stomach Neoplasms ; metabolism ; pathology ; Tumor Suppressor Protein p53 ; analysis