Li Ranran, Zhang Ying, Yuan Yuan, Lin Qi, Dai Jianjian, Xu Ruicai, Hu Xudong, Han Mingyong
Cancer Therapy and Research Center, Shandong Provincial Hospital affiliated to Shandong University, Jinan, P. R. China.
Department of Radiation Oncology, Shandong Cancer Hospital affiliated to Shandong University, Jinan, P. R. China.
PLoS One. 2017 Nov 9;12(11):e0187390. doi: 10.1371/journal.pone.0187390. eCollection 2017.
This study aimed to assess the dosimetric differences between iodine-125 seed stereotactic brachytherapy (SBT) and stereotactic body radiation therapy (SBRT) in the treatment of non-small cell lung cancer (NSCLC). An SBT plan and an SBRT plan were generated for eleven patients with T1-2 NSCLC. Prescription of the dose and fractionation (fr) for SBRT was 48Gy/4fr. The planning aim for SBT was D90 (dose delivered to 90% of the target volume)≥120Gy. Student's paired t test was used to compare the dosimetric parameters. The SBT and SBRT plans had comparable PTV D90 (104.73±2.10Gyvs.107.64±2.29Gy), and similar mean volume receiving 100% of the prescription dose (V100%) (91.65% vs.92.44%, p = 0.410). The mean volume receiving 150% of the prescribed dose (V150%) for SBT was 64.71%, whereas it was 0% for SBRT. Mean heterogeneity index (HI) deviation for SBT vs. SBRT was 0.73 vs. 0.19 (p<0.0001), and the mean conformity index (CI) for SBT vs. SBRT was 0.77 vs. 0.81 (p = 0.031). The mean lung doses (MLD) in SBT were significantly lower than those in SBRT (1.952±0.713 vs. 5.618±2.009, p<0.0001). In conclusion, compared with SBRT, SBT can generate a comparable dose within PTV, while the organs at risk (OARs) only receive a very low dose. But the HI and CI in SBT were lower than in SBRT.
本研究旨在评估碘-125粒子立体定向近距离放射治疗（SBT）与立体定向体部放射治疗（SBRT）在治疗非小细胞肺癌（NSCLC）时的剂量学差异。为11例T1-2期NSCLC患者制定了SBT计划和SBRT计划。SBRT的剂量和分割方案为48Gy/4次分割。SBT的计划目标是D90（给予90%靶体积的剂量）≥120Gy。采用配对t检验比较剂量学参数。SBT和SBRT计划的计划靶体积（PTV）D90相当（104.73±2.10Gy对107.64±2.29Gy），接受100%处方剂量的平均体积（V100%）相似（91.65%对92.44%，p = 0.410）。SBT接受150%处方剂量的平均体积（V150%）为64.71%。而SBRT为0%。SBT与SBRT的平均异质性指数（HI）偏差分别为0.73和0.19（p<0.0001），SBT与SBRT的平均适形指数（CI）分别为0.77和0.81（p = 0.031）。SBT的平均肺剂量（MLD）显著低于SBRT（1.952±0.713对5.618±2.009, p<0.0001）。总之，与SBRT相比，SBT可在PTV内产生相当的剂量，而危及器官（OARs）仅接受非常低的剂量。但SBT的HI和CI低于SBRT。
