ABSTRACT
<p><b>OBJECTIVE</b>To investigate the difference of local immune microenvironment in primary tumors between liver-metastasis and non-liver-metastasis cohort in stage III to IIII colorectal cancer patients.</p><p><b>METHODS</b>Tumor samples from 167 patients of colorectal cancer were harvested, who received tumor resection for the first time in The First Affiliated Hospital of Sun Yat-sen University from 2000 to 2005. Patients were divided into two groups according to liver metastasis or not. Expressions of 18 immune markers, including CD3, CD4 and CD8 were examined and quantified by immunohistochemistry staining.</p><p><b>RESULTS</b>No significant differences of gender, age, BMI, tumor differentiation, pathology type and preoperative CEA level were found between the two groups. The expressions of CD8, CD45RO, IL-17, tryptase and FAS were lower in liver-metastasis group as compared to non-liver-metastasis group (all P<0.05).</p><p><b>CONCLUSIONS</b>Decrease of the number of T lymphocyte and mast cell may play an important role in local infiltration of immune microenvironment of stage III to IIII colorectal cancer with liver metastasis.</p>