Capecitabine, Cetuximab, Oxaliplatin, and Bevacizumab in Treating Patients With Metastatic or Recurrent Colorectal Cancer That Cannot Be Removed By Surgery

RATIONALE: Drugs used in chemotherapy, such as capecitabine and oxaliplatin, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Giving more than one drug (combination chemotherapy) may kill more tumor cells. Monoclonal antibodies, such as cetuximab and bevacizumab, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry tumor-killing substances to them. Cetuximab and bevacizumab may also stop the growth of tumor cells by blocking blood flow to the tumor. Giving capecitabine together with cetuximab, oxaliplatin, and bevacizumab may kill more tumor cells.
PURPOSE: This phase II trial is studying how well giving capecitabine together with cetuximab, oxaliplatin, and bevacizumab works in treating patients with metastatic or recurrent colorectal cancer that cannot be removed by surgery.

【治疗原理】：化疗常用药物如卡培他滨（capecitabine）、奥沙利铂（oxaliplatin），可通过多种机制抑制肿瘤细胞增殖，既可直接杀伤肿瘤细胞，亦可阻断其分裂进程。联合应用多种化疗药物（即联合化疗，combination chemotherapy）可杀伤更多肿瘤细胞。单克隆抗体（monoclonal antibody）类药物如西妥昔单抗（cetuximab）、贝伐珠单抗（bevacizumab），可通过不同途径阻断肿瘤生长：部分单克隆抗体可抑制肿瘤细胞的增殖与转移能力，另有部分可特异性识别肿瘤细胞，协助杀伤肿瘤细胞或向其递送抗肿瘤活性物质。西妥昔单抗与贝伐珠单抗还可通过阻断肿瘤组织的血液供应，进而抑制肿瘤细胞增殖。联合应用卡培他滨、西妥昔单抗、奥沙利铂与贝伐珠单抗，可进一步提升肿瘤细胞杀伤效果。
【试验目的】：本项II期临床试验（phase II trial）旨在评估卡培他滨联合西妥昔单抗、奥沙利铂及贝伐珠单抗方案，治疗无法手术切除的转移性或复发性结直肠癌患者的临床疗效。