目的　研究A、B期直肠癌淋巴结微转移的特点 ,分析微转移与各种临床病理因素及预后的关系。方法　选用鼠抗人细胞角蛋白 2 0 (CK2 0 )单克隆抗体 ,运用免疫组化方法 ,检测 5 7例A、B期直肠癌根治标本的直肠周围淋巴结 183个 ,并进行统计学处理。结果　 2 5例 ( 4 3 .9% )直肠癌的 48个淋巴结 ( 2 6.2 % )出现微转移。淋巴结微转移与原发肿瘤的大小、分化程度、肿瘤的部位有关 ,但与年龄、性别及原发肿瘤侵入的深度无关。随访平均 42个月结束后 ,有微转移的直肠癌患者生存率 ( 74.9% )与无微转移的直肠癌患者 ( 78.8% )无明显差异。结论　直肠癌微转移可能增加局部复发或远处转移的发生 ,但对预后无明显关系 Objective To study the characteristics of lymph node micrometastasis in stage A and B rectal cancer and to analyze the relationship between micrometastasis and various clinical pathological factors and prognosis. Methods The mouse anti-human cytokeratin 20 (CK20) monoclonal antibody was used to detect 183 rectal lymph nodes in 57 patients with rectal cancer of stage A and B by immunohistochemistry and the data were statistically analyzed. Results Micrometastases occurred in 48 lymph nodes (26.2%) in 25 cases (43.9%) of rectal cancer. Lymph node micrometastasis is related to the size and differentiation of the primary tumor and the location of the tumor, but it has no relation with the age, sex and depth of primary tumor invasion. After an average of 42 months of follow-up, there was no significant difference in survival between patients with micrometastases in rectal cancer (74.9%) and those without micrometastases (78.8%). Conclusion Micrometastasis of rectal cancer may increase the occurrence of local recurrence or distant metastasis, but it has no significant relationship with prognosis