A Clinical Trial Comparing Preoperative Radiation Therapy And Capecitabine With or Without Oxaliplatin With Preoperative Radiation Therapy And Continuous Intravenous Infusion Of 5-Fluorouracil With or Without Oxaliplatin In The Treatment Of Patients With Operable Carcinoma Of The Rectum

RATIONALE: Drugs used in chemotherapy, such as capecitabine, fluorouracil, and oxaliplatin
work in different ways to stop tumor cells from dividing so they stop growing or die.
Radiation therapy uses high-energy x-rays to damage tumor cells.

PURPOSE: This randomized phase III trial is studying radiation therapy and either
capecitabine or fluorouracil with or without oxaliplatin and comparing them to see how well
they work when given before surgery in treating patients with resectable rectal cancer. It is
not yet known whether radiation therapy and either capecitabine or fluorouracil is more
effective with or without oxaliplatin in treating rectal cancer.

研究依据：化疗药物如卡培他滨（capecitabine）、氟尿嘧啶（fluorouracil）及奥沙利铂（oxaliplatin）可通过不同作用机制阻断肿瘤细胞分裂，使肿瘤细胞增殖停滞或发生凋亡。放疗（radiation therapy）通过高能X射线损伤肿瘤细胞。
试验目的：本项随机III期临床试验（phase III trial）旨在评估术前联合放疗联合卡培他滨或氟尿嘧啶±奥沙利铂方案治疗可切除直肠癌（resectable rectal cancer）的临床疗效，并对比不同给药方案的治疗效果。目前尚不明确在放疗联合卡培他滨或氟尿嘧啶的基础上加用奥沙利铂，是否可提升直肠癌的治疗效果。