MRI联合CT定位在局部进展期低位直肠癌新辅助放化疗中的应用

Application of MRI and CT simulation in neoadjuvant chemoradiotherapy for patients with locally advanced low rectal cancer

目的探讨MRI联合CT定位在局部进展期低位直肠癌新辅助放化疗中应用价值。方法回顾性分析70例初治局部进展期低位直肠癌患者临床资料,分别采用CT定位(对照组)或MRI联合CT定位(观察组)勾画靶区。比较两组肿瘤分期、大体肿瘤靶区(GTV)体积、GTV长度、GTV下界距肛缘距离、不良反应。结果与对照组相比,观察组GTV体积明显缩小,GTV长度明显变短,GTV下界距肛缘距离明显增长,Ⅱ~Ⅲ度骨髓抑制和胃肠道反应发生率明显降低(P<0.01或0.05)。结论MRI联合CT定位对局部进展期低位直肠癌勾画靶区更准确,可降低骨髓抑制和胃肠道反应发生率。

Objective To investigate the application value of combined MRI and CT localization in neoadjuvant chemoradiotherapy for patients with locally advanced low rectal cancer(LALRC).Methods Clinical data of 70 patients with LALRC were retrospectively analyzed.The target area was delineated by CT(control group)or MRI plus CT(observation group).The tumor stage,gross tumor volume(GTV),GTV length,distance between GTV lower boundary and anal margin,and adverse reactions were compared between two groups.Results Compared with control group,GTV volume and length was lower,distance between GTV lower boundary and anal margin was longer,and Ⅱ~Ⅲ degree myelosuppression and gastrointestinal reactions were decreased in observation group(P<0.01 or 0.05).Conclusion Combined MRI and CT is more accurate in delineating the target area in patients with LALRC,and can reduce the incidence of myelosuppression and gastrointestinal reactions.