大肠癌是常见的恶性肿瘤。近 2 0年来 ,大肠根治术的方法不断改进 ,但是患者的预后并未明显改善 ,大约 5 0 %的患者死于腹腔局部或区域的复发和肝转移 ,而癌细胞在腹腔内、淋巴结、骨髓及外周血中的微转移则是导致大肠癌术后复发转移的重要因素。因此 ,及时发现微转移不仅对大 Colorectal cancer is a common malignancy. In the recent 20 years, the method of radical operation of the colon has been continuously improved, but the prognosis of the patients has not been significantly improved. About 50% of the patients die of local or regional recurrence and liver metastasis in the abdominal cavity. However, cancer cells in the abdominal cavity, lymph nodes, And micrometastasis in peripheral blood are the important factors leading to recurrence and metastasis of colorectal cancer. Therefore, timely detection of micrometastases not only for large