Abstract：
OBJECTIVE: Surgically targeted radiation therapy (STaRT) with Cesium-131 seeds embedded in a collagen tile is a promising treatment for recurrent brain metastasis. In this study, the biological effective doses (BED) for normal and target tissues from STaRT plans were compared with those of external beam radiotherapy (EBRT) modalities.
METHODS: Nine patients (n = 9) with 12 resection cavities (RCs) who underwent STaRT (cumulative physical dose of 60 Gy to a depth of 5 mm from the RC edge) were replanned with CyberKnifeⓇ (CK), Gamma KnifeⓇ (GK), and intensity modulated proton therapy (IMPT) using an SRT approach (30 Gy in 5 fractions). Statistical significance comparing D95% and D90% in BED10Gy (BED10Gy95% and BED10Gy90%) and to RC + 0 to + 5 mm expansion margins, and parameters associated with radiation necrosis risk (V83Gy, V103Gy, V123Gy and V243Gy) to the normal brain were evaluated by a Wilcoxon-signed rank test.
RESULTS: For RC + 0 mm, median BED10Gy 90% for STaRT (90.1 Gy10, range: 64.1-140.9 Gy10) was significantly higher than CK (74.3 Gy10, range:59.3-80.4 Gy10, p = 0.04), GK (69.4 Gy10, range: 59.8-77.1 Gy10, p = 0.005), and IMPT (49.3 Gy10, range: 49.0-49.7 Gy10, p = 0.003), respectively. However, for the RC + 5 mm, the median BED10Gy 90% for STaRT (34.1 Gy10, range: 22.2-59.7 Gy10) was significantly lower than CK (44.3 Gy10, range: 37.8-52.4 Gy10), and IMPT (46.6 Gy10, range: 45.1-48.5 Gy10), respectively, but not significantly different from GK (34.1 Gy10, range: 22.8-47.0 Gy10). The median V243Gy was significantly higher in CK (11.7 cc, range: 4.7-20.1 cc), GK(6.2 cc, range: 2.3-11.9 cc) and IMPT (19.9 cc, range: 11.1-36.6 cc) compared to STaRT (1.1 cc, range: 0.0-7.8 cc) (p < 0.01).
CONCLUSIONS: This comparative analysis suggests a STaRT approach may treat recurrent brain tumors effectively via delivery of higher radiation doses with equivalent or greater BED up to at least 3 mm from the RC edge as compared to EBRT approaches.
METHODS: Nine patients (n = 9) with 12 resection cavities (RCs) who underwent STaRT (cumulative physical dose of 60 Gy to a depth of 5 mm from the RC edge) were replanned with CyberKnifeⓇ (CK), Gamma KnifeⓇ (GK), and intensity modulated proton therapy (IMPT) using an SRT approach (30 Gy in 5 fractions). Statistical significance comparing D95% and D90% in BED10Gy (BED10Gy95% and BED10Gy90%) and to RC + 0 to + 5 mm expansion margins, and parameters associated with radiation necrosis risk (V83Gy, V103Gy, V123Gy and V243Gy) to the normal brain were evaluated by a Wilcoxon-signed rank test.
RESULTS: For RC + 0 mm, median BED10Gy 90% for STaRT (90.1 Gy10, range: 64.1-140.9 Gy10) was significantly higher than CK (74.3 Gy10, range:59.3-80.4 Gy10, p = 0.04), GK (69.4 Gy10, range: 59.8-77.1 Gy10, p = 0.005), and IMPT (49.3 Gy10, range: 49.0-49.7 Gy10, p = 0.003), respectively. However, for the RC + 5 mm, the median BED10Gy 90% for STaRT (34.1 Gy10, range: 22.2-59.7 Gy10) was significantly lower than CK (44.3 Gy10, range: 37.8-52.4 Gy10), and IMPT (46.6 Gy10, range: 45.1-48.5 Gy10), respectively, but not significantly different from GK (34.1 Gy10, range: 22.8-47.0 Gy10). The median V243Gy was significantly higher in CK (11.7 cc, range: 4.7-20.1 cc), GK(6.2 cc, range: 2.3-11.9 cc) and IMPT (19.9 cc, range: 11.1-36.6 cc) compared to STaRT (1.1 cc, range: 0.0-7.8 cc) (p < 0.01).
CONCLUSIONS: This comparative analysis suggests a STaRT approach may treat recurrent brain tumors effectively via delivery of higher radiation doses with equivalent or greater BED up to at least 3 mm from the RC edge as compared to EBRT approaches.
摘要：
目的：将铯131种子包埋在胶原块中的手术靶向放射治疗（STaRT）是治疗复发性脑转移的有希望的治疗方法。在这项研究中,将来自STaRT计划的正常组织和靶组织的生物有效剂量(BED)与外部束放疗(EBRT)方式的生物有效剂量(BED)进行了比较.
方法：用CyberKnife®(CK)重新扫描9例(n=9)有12个切除腔(RC)的患者接受STaRT(累积物理剂量为60Gy至距离RC边缘5mm的深度)。伽马射线(GK),和使用SRT方法(5个部分中的30Gy)的强度调节质子治疗(IMPT)。比较BED10Gy中的D95%和D90%(BED10Gy95%和BED10Gy90%)和RC+0至+5mm扩展边缘的统计学显著性,和与放射性坏死风险相关的参数(V83Gy，V103Gy,通过Wilcoxon符号秩检验评估正常大脑的V123Gy和V243Gy）。
结果：对于RC+0mm，STaRT的BED10Gy中位数90％（90.1Gy10，范围：64.1-140.9Gy10）显着高于CK（74.3Gy10，范围：59.3-80.4Gy10，p=0.04），GK（69.4Gy10，范围：59.8-77.1Gy10，p=0.005），和IMPT（49.3Gy10，范围：49.0-49.7Gy10，p=0.003），分别。然而,对于RC+5毫米，STaRT的中位数BED10Gy90％（34.1Gy10，范围：22.2-59.7Gy10）显着低于CK（44.3Gy10，范围：37.8-52.4Gy10），和IMPT（46.6Gy10，范围：45.1-48.5Gy10），分别,但与GK（34.1Gy10，范围：22.8-47.0Gy10）没有显着差异。CK的V243Gy中位数明显更高（11.7cc，范围：4.7-20.1cc），GK(6.2cc,范围：2.3-11.9cc）和IMPT（19.9cc，范围：11.1-36.6cc）与STaRT（1.1cc，范围：0.0-7.8cc）（p<0.01）。
结论：该比较分析表明，与EBRT方法相比，STaRT方法可以通过在距RC边缘至少3mm处的等效或更大BED递送更高的辐射剂量来有效治疗复发性脑肿瘤。
方法：用CyberKnife®(CK)重新扫描9例(n=9)有12个切除腔(RC)的患者接受STaRT(累积物理剂量为60Gy至距离RC边缘5mm的深度)。伽马射线(GK),和使用SRT方法(5个部分中的30Gy)的强度调节质子治疗(IMPT)。比较BED10Gy中的D95%和D90%(BED10Gy95%和BED10Gy90%)和RC+0至+5mm扩展边缘的统计学显著性,和与放射性坏死风险相关的参数(V83Gy，V103Gy,通过Wilcoxon符号秩检验评估正常大脑的V123Gy和V243Gy）。
结果：对于RC+0mm，STaRT的BED10Gy中位数90％（90.1Gy10，范围：64.1-140.9Gy10）显着高于CK（74.3Gy10，范围：59.3-80.4Gy10，p=0.04），GK（69.4Gy10，范围：59.8-77.1Gy10，p=0.005），和IMPT（49.3Gy10，范围：49.0-49.7Gy10，p=0.003），分别。然而,对于RC+5毫米，STaRT的中位数BED10Gy90％（34.1Gy10，范围：22.2-59.7Gy10）显着低于CK（44.3Gy10，范围：37.8-52.4Gy10），和IMPT（46.6Gy10，范围：45.1-48.5Gy10），分别,但与GK（34.1Gy10，范围：22.8-47.0Gy10）没有显着差异。CK的V243Gy中位数明显更高（11.7cc，范围：4.7-20.1cc），GK(6.2cc,范围：2.3-11.9cc）和IMPT（19.9cc，范围：11.1-36.6cc）与STaRT（1.1cc，范围：0.0-7.8cc）（p<0.01）。
结论：该比较分析表明，与EBRT方法相比，STaRT方法可以通过在距RC边缘至少3mm处的等效或更大BED递送更高的辐射剂量来有效治疗复发性脑肿瘤。
