结直肠癌(colorectal cancer,CRC)是世界上发生率第三的恶性肿瘤[1],是常见的消化道肿瘤。目前,手术治疗是惟一可能根治CRC的方法,如果能够早期诊断,Ⅰ期患者的5年生存率可达93%,但CRC患者早期并无明显症状,往往发现时已失去手术机会,Ⅳ期患者的5年生存率只有8%[2]。另一方面,CRC治疗方案的制定主要基于肿瘤的TNM分期[3],由于不能从基因层面上鉴别高危人群和低危人群,患者常因治疗不充分或治疗过量而影响治疗效果 Colorectal cancer (CRC) is the third most common malignancy in the world [1] and is a common gastrointestinal tumor. At present, surgical treatment is the only way to cure CRC. If it can be diagnosed early, the 5-year survival rate of stage Ⅰ patients can reach 93%. However, patients with CRC have no obvious symptoms in the early stage and often have lost the chance of surgery. Stage Ⅳ patients 5-year survival rate of only 8% [2]. On the other hand, the development of CRC regimens is mainly based on the TNM stage of the tumor [3]. Patients often fail to identify the high-risk and low-risk groups at the genetic level, and the patients are often affected by inadequate treatment or overdose