低位直肠癌术前调强放疗同步加量并同步口服卡培他滨化疗的初步研究

目的探讨低位直肠癌调强放射治疗（IMRT）同步加量并同步口服卡培他滨化疗的毒副作用,并初步分析其疗效。方法回顾性分析16例接受术前IMRT同步加量放疗同时口服希罗达化疗,临床诊断为T_（2～4）和/或N_（1～2）的低位直肠腺癌患者,放射治疗采用5野IMRT技术,共25次5周,全盆腔45～50Gy,肿瘤及其周围2cm范围同步加量至55～60Gy。同时口服卡培他滨625mg/m~2,每日2次,应用2周后休息1周,再继续口服至放疗结束。手术于放疗结束后8～10周进行。记录分析所有病例的毒副作用及远近期疗效。结果所有病例顺利完成治疗,无治疗中断者。有11例患者（68.8%）出现Ⅲ度皮肤反应,无Ⅲ度以上腹泻、血液学及泌尿系统毒副作用,仅1例患者（6.3%）出现晚期Ⅱ度胃肠道毒副作用。放疗后评估临床完全缓解7例（43.8%）,部分缓解8例（50%）。12例（75%）患者保肛,其中手术并保肛7例,肿物消失拒绝手术5例。2年总生存率85.7%,无病生存率76.6%,局部复发率6.3%。结论低位直肠癌调强放射治疗（IMRT）同步加量并同步口服卡培他滨化疗有一定效果且患者耐受良好,值得进一步探索研究。

A preliminary analysis of preoperative intensity-modulated radiotherapy and an incorporated boost with concurrent capecitabine for distal rectal cancer

Objective To explore the safety and efficacy of preoperative intensity-modulated radiotherapy（IMRT） and an incorporated boost with concurrent capecitabine in patients with distal rectal cancer.Methods and Materials Totally 16 patients with T2-T4 and/or N1-N 2 primary rectal cancer who received preoperative IMRT with an incorporated boost and concurrent capecitabine were retrospectively analyzed. Photon IMRT and an incorporated boost were used to irradiate the whole pelvis to 45 Gy and the gross tumor volume plus 2 cm margin to 55-60 Gy in 25 fractions within 5 weeks.Capecitabine was orally given at 625 mg/m~2 twice daily for 14 days,and after a 7-day break,the drug was continued until the end of radiotherapy.Operation was performed 8-10 weeks after the end of radiochemotherapy.All the toxicities,treatment response,and long term results were recoreded and analyzed.Results All patients completed the treatment without any treatment break.Eleven patients experienced Grade 3 acute skin toxicity. No patients had Grade 3 or 4 diarrhea,and no Grade 3 or 4 acute blood or urinary toxicities were observed.Only one patient had Grade 2 gastrointestinal late toxicity.Seven out of the 16 patients had clinically complete response,and 8 partial response.Seven patients underwent function-sparing surgery. Five patients refused surgery because tumor disappeared.The 2-year overall survival rate,2-year disease free -survival rate,and the 2-year local and regional recurrent rate were 85.7%,76.6%,and 6.3%, respectively.Conclusion For patients with distal rectal cancer,preoperative radiotherapy using intensity -modulated radiotherapy（IMRT） and an incorporated boost with concurrent capecitabine is safe and acceptable. Further investigation need to be done for validation of this treatment modality.