局部进展期直肠癌术前放化疗的疗效评价

目的 分析临床病理变化特征,对局部进展期直肠癌手术前放化疗的进行评价。方法 36例局部进展期直肠癌患者行手术前放化疗。放疗总剂量为45Gy,每周5次,每次1.8Gy。全身化疗共2个疗程,四氢叶酸（folinic acid,FA)50mg,静脉滴入,随后静脉给予5－Fu 300mg/m^2。手术后2－4周开始追加2－4个疗程化疗。辅助治疗完成后4－6周采取手术治疗。结果 仅有2例（5．6％）患者出现Ⅲ度造血系统毒性反应,全组未出现Ⅲ-Ⅳ度胃肠反应、皮肤或泌尿系急性毒性反应。全部患者均采取手术治疗,全组无围手术期死亡,手术并发症为13．8％,未发生远期并发症。经过术前辅助治疗,肿瘤的平均直径平均缩小28．0％。4例（11．1％）达到病理完全缓解,病理总有效率（CR＋PR）为77．8％,肿瘤分期下降率达到52．8％。辅助治疗后,淋巴结的阴转率达到60．0％,淋巴结总阳性率由83．0％降至37．0％。结论 术前放疗＋全身化疗安全可靠,能使部分肿瘤病理完全缓解,缩小原发瘤,减少了局部淋巴结转移率,从而达到降低肿瘤分期,提高了手术的疗效。

Tumor downstaging through preoperative chemoradiotherapy in locally advanced rectal cancer

OBJECTIVE: To evaluate the impact of preoperative chemoradiotherapy on patients with locally advanced rectal cancer by clinical and pathological characteristics. METHODS: From July 1994 to May 1995, 36 patients with locally advanced rectal cancer were treated. Pathology: adenocarcinoma 27, mucinous adenocarcinoma 7 and ductal adenocarcinoma 6. The protocol was carried out in sequence of chemo-->radio-->surgery-->chemotherapy. The treatment began with preoperative chemotherapy with folinic acid 50 mg followed by 5-FU bolus of 300 mg/m2 given for two cycles on d1-5 and d22-26 before irradiation. Radiation therapy was delivered to a dose of 45 Gy, 1.8 Gy per fraction, 5 days a week. Surgery was done 4-6 weeks after this preoperative treatments. Another 2 to 4 cycles of chemotherapy were added 2 to 4 weeks after operation. Twenty-one patients were treated by Dixon's operation, 14 patients by Mile's operation and 1 by local tumorectomy through the rectum. Radical operation was performed in 29 patients and palliative resection was done in 7 patients. RESULTS: Grade III hematological toxicity was observed in only 2(5.6%) patients. No patient had grade III or IV acute toxicity in the gastrointestinal, skin or urological systems. All patients underwent surgery. The perioperative morbidity rate was 13.8% with no mortality or late toxicity. As a result of this preoperative management, the tumor was reduced by an average of 28.0%, with a complete pathological response in 4(11.1%) patients. In 28 CR + PR (77.8%) patients, a downstaging in 19(52.8%) patients was observed. Sixty percent of positive lymph nodes as assessed by transrectal ultrasonography before therapy became pathologically negative postoperatively, with the frequency of lymph node metastasis decreased by 46.0%(83.0% to 37.0%). CONCLUSION: Preoperative radiochemotherapy is proved as a safe method with a tolerable toxicity. Complete pathological response, shrinkage of the primary tumor and decrease in lymph node metastasis are observed after preoperative radiochemotherapeutic regimen. An overall benefit of downstaging the primary tumor and a greatly enhanced effect of surgery is enjoyed by the patients.