转移性结直肠癌维持治疗的研究现状与治疗策略

Research status and treatment strategies of maintenance therapy for metastatic colorectal cancer

结直肠癌是常见的恶性肿瘤之一,其发病率和死亡率分别位于第三位和第四位。大约60%的患者确诊时已处于晚期,其5年生存率在13%左右。近20年来,由于转移性结直肠癌(mCRC)晚期一线化疗方案及靶向药物的规范化应用,mCRC的治疗获得了重大突破。奥沙利铂、卡培他滨、贝伐珠单抗、西妥昔单抗等药物的应用使患者的中位生存期提高了一倍,5年生存率提高了20%。mCRC晚期一线治疗的常规模式是持续用药,直至病情进展或出现不可耐受的毒性。但是由于化疗药物的毒性累积,只有三分之一的患者能够坚持接受治疗直至病情进展。而患者在完成既定的初始化疗周期数,达到CR/PR/SD后,继续采用低剂量、低毒性的药物进行维持治疗,既可以延缓肿瘤的进展和转移,又可以减轻药物的毒副作用。目前,维持治疗已经成为mCRC晚期一线化疗后的主要治疗模式。但是,mCRC的最佳维持治疗方案仍无定论,现有的维持治疗方案仍不能找到最佳疗效与最大生活质量之间的平衡点。本文将回顾mCRC现有的维持治疗方案的临床研究,总结mCRC维持治疗现状,并对个体化的治疗策略进行讨论。

Colorectal cancer is one of the common malignant tumors,and its morbidity and mortality are in the third and fourth places,respectively.About 60% of patients are in an advanced stage at the diagnosis,and their 5-year survival rate is around 13%.In the past 20 years,since the standardized application of advanced first-line chemotherapy and targeted drugs for metastatic colorectal cancer(mCRC),mCRC treatment has made a major breakthrough.The use of oxaliplatin,capecitabine,bevacizumab,cetuximab and other drugs have doubled the median survival and increased the 5-year survival rate by 20%.The usual mode of first-line treatment of mCRC in the late stage is continuous medication until the disease progress or the intolerable toxicity occurs.However,because of the accumulation of toxicity of chemotherapy drugs,only one-third of patients can continue to receive treatment until the disease progresses.After completing established initial treatment cycle and achieving CR/PR/SD,the patients continue to use low-dose,low-toxic drugs for maintenance treatment,which can delay the progression and metastasis of the tumor,and reduce the side effects of drug.At present,maintenance therapy has become the main treatment mode after advanced first-line chemotherapy for mCRC.However,the optimal maintenance regimen for mCRC remains inconclusive,and existing maintenance regimens still do not find a balance between optimal outcome and maximum quality of life.This article will review the clinical studies of mCRC′s existing maintenance treatment regimens,summarize the current status of mCRC maintenance therapy,and discuss individualized treatment strategies.