NSCLC肺部小病灶非均整模式立体定向放疗的应用

Stereotactic Radiotherapy for Non-small Cell Lung Cancer with Small Lesions Applying A Flattening Filter Free Clinac

背景与目的随着放疗技术的快速发展,立体定向放射治疗(stereotactic body radiation therapy,SBRT)已得到广泛应用,且在早期非小细胞肺癌(non-small cell lung cancer,NSCLC)治疗中取得与手术相当的疗效。非均整模式移除了加速器的射野均整器,其剂量率远高于常规均整模式,缩短治疗时间,但目前临床应用较少。本研究旨在探讨非均整模式SBRT治疗的安全性和有效性。方法选取2011年12月-2013年12月期间的T1-2N0M0原发NSCLC,术后肺内孤立复发转移,以及IV期肺内寡转移灶者共31例,予以内在大体肿瘤靶区60 Gy/8 f或48 Gy/4 f的非均整模式SBRT治疗。结果非均整模式比常规均整模式明显缩短了治疗时间,靶区剂量相当,且未增加正常组织受量。患者中位随访时间为19.4个月。1年的局部控制、区域控制、远处转移控制、无疾病进展和总生存率分别为96.8%、96.8%、83.9%、77.4%和96.8%。最常见的副反应为放射性肺炎(1级29%,2级3.2%)和胸痛(1级12.9%,2级6.5%),发生率较低。结论相比既往常规均整模式,使用非均整模式大分割放射治疗技术治疗肺部小肿瘤是安全、有效的,但长期效果仍需进一步随访、研究。

Background and objective With the rapid development of technology, stereotactic radiotherapy has been widely used. In a cohort of medically operable non-small cell lung cancer patients receiving stereotactic body radiation therapy （SBRT） survival rates“potentially equivalent to those of surgery”have been reported. Removing the ifeld lfattening iflter, Clinac is capable of delivering dose rates much higher than conventional linac as well as reducing the treatment time. hTe goals of this work were to report safety and effcacy of SBRT treatment using a lfattening iflter-free model for non-small cell lung cancer （NSCLC） with small lesions. Methods From December 2011 to December 2013, 31 NSCLC patients who were T1-2N0M0, solitary pulmonary recurrence atfer surgery, and stage IV with oligo metastasis were enrolled, receiving SBRT treatment （60 Gy/8 f or 48 Gy/4 f ） applying a lfattening iflter-free model. Results Compared with conventional technique, lfat-tening iflter-free model shortened the treating time with equivalent target dose and normal tissue dose. hTe median follow-up time is 19.4 mo. hTe 1-yr local control, regional control, distant control, progression free survival and overall survival rates were 96.8%, 96.8%, 83.9%, 77.4%and 96.8%. hTe most common side effects were radiation pneumonitis （29%grade 1, 3.2%grade 2） and chest pain （12.9%grade 1, 6.5%grade 2）. Conclusion hTe use of lfattening iflter-free model in SBRT for small lesions of NSCLC patients is safe and effective. Long time follow-up and additional studies are still needed to validate our conclusions.