不同追踪方式对射波刀治疗肺肿瘤近期疗效的影响

目的 探讨金标、椎体实时追踪对射波刀治疗肺部肿瘤近期疗效的影响。
方法 回顾分析射波刀治疗肺部肿瘤患者 64例72个病灶,其中原发瘤 40例41个病灶,转移瘤 24例31个病灶。45个病灶采用金标追踪,27例患者采用椎体追踪。70%~94%(中位数80%)等剂量线覆盖计划把体积,照射剂量60 Gy分3次。比较两者近期疗效与追踪方式的关系。
结果 全部病灶有效率金标追踪好于椎体追踪(93%∶74%,χ²=6.84,P=0.033),下肺病灶的也如此(15%∶7%,χ²=7.18,P=0.028),但上肺病灶的两者相似(28%∶12%,χ²=2.36,P=0.310),治疗体积<15 cm³金标追踪好于椎体追踪(25%∶12%,χ²=6.53,P=0.038),而≥15 cm³的两者相似(17%∶8%,χ²=1.57,P=0.460)。全部病灶椎体追踪治疗失败率比金标追踪高(19%∶2%,χ²=6.33,P=0.021)。
结论 不同追踪方式与射波刀治疗肺部肿瘤近期疗效有关,并受病灶位置、治疗体积影响。

Impacts of different tracking methods on short-term therapeutic effect of cyberknife in treatment of lung cancer

Objective To investigate the impacts of fiducial tracking and X-sight tracking on the short-term therapeutic effect of cybernikife in the treatment of lung cancer.
Methods Retrospective analysis was performed on 64 lung cancer patients (72 lesions), including 40 primary tumor patients (41 lesions) and 24 metastatic tumor patients (31 lesions), who were treated with cyberknife. Fiducial tracking was used for 45 lesions, while X-sight tracking was used for 27 lesions. The planning target volume was covered by 70%—94%(median 80%) isodose contour. The irradiation dose was 60 Gy/3 fractions. The relationship between short-term therapeutic effect and tracking method was determined.
Results Overall, the lesions undergoing fiducial tracking showed significantly higher response rate than those undergoing X-sight tracking (93% vs. 74%, χ²=6.84,P=0.033), and so was in lower lung lesions (15% vs. 7%, χ²=7.18,P=0.028). But the two tracking methods achieved similar effects in upper lung lesions (28% vs. 12%, χ²=2.36,P=0.310). In the lesions with treatment volumes smaller than 15 cm³, the fiducial tracking achieved significantly higher response rate than the X-sight tracking (25% vs. 12%, χ²=6.53,P=0.038), but the two tracking methods achieved similar effects in the lesions with treatment volumes not smaller than 15 cm³(17% vs 8%, χ²=1.57,P=0.460). Overall, the lesions undergoing X-sight tracking had significantlyhigher treatment failure rate than fiducial tracking (19% vs. 2%, χ²=6.33,P=0.021).
Conclusions Different tracking methods may lead to different therapeutic effects of cyberknife in the treatment of lung cancer, which are related to lesion location and treatment volume.