胃癌调强放疗中非共面锁野计划与共面锁野计划的剂量学比较

Dosimetric difference between non-coplanar field and fixed-jaw field intensity modulated radiotherapy for gastric carcinoma

目的:通过比较胃癌调强放疗中共面锁野计划与非共面锁野计划的剂量学差异,为临床放疗方案的选择提供参考依据。方法:选取10例胃癌患者分别制定9野的共面锁野调强和9野非共面锁野调强的治疗计划,比较机器跳数、靶区和危及器官等参数的剂量学差异。结果:两种计划均满足临床需求。非共面计划相比锁野计划仅小肠的V20显著降低且差异具有统计学意义。对于右肾脏、肝脏、脊髓和小肠的Dmean,非共面计划略低于共面锁野计划,但参数差异均无统计学意义。结论:非共面技术相比与锁野技术在9野胃癌放疗中并未取得明显优势,从技术层面考虑,非共面技术需要转床可能会引入一些误差,所以笔者建议使用共面锁野技术。

Objective:To evaluate the non-coplanar field and fixed-jaw field intensity modulated radiotherapy(IMRT)for gastric carcinoma.Methods:Dosimetric comparisons between non-coplanar field and fixed-jaw field technique used for IMRT treatment were presented.Twelve patients with gastric carcinoma were studied and compared with both techniques.Optimal parameters used in gastric carcinoma were kept the same for both techniques.Results:For the small intestine,the V20 values in the noncoplanar field technique decreased as compared with those in the fixed-jaw field technique.For the right kidney,liver,spinal cord,and small intestine,the Dmean values in the non-coplanar field technique were decrease as compared with those in the fixed-jaw field technique,the other results were opposite.However,there were no significant difference for these parameters(P>0.05).Conclusion:Non-coplanar field technique has no obvious advantage when compared with fixed-jaw field technique in 9 fields IMRT for gastric carcinoma.