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Objective:To evaluate the accuracy and stability of stereotactic radiosurgery (SRS) algorithm in optical surface imaging (OSI) system in non-coplanar radiotherapy.Methods:Three OSI imaging systems were used to measure the phantom repeatedly at different couch rotation angles to analyze the accuracy and stability of OSI system. Seven patients with multiple brain metastases who underwent single-center non-coplanar radiotherapy were randomly selected, and the accuracy and stability of OSI for patient imaging were analyzed. Stability is defined as the difference between the two OSI measurements when the couch is turned from 0° to a non 0° angle, and then back to 0°, using the 0° cone beam CT (CBCT) as the "gold standard". Accuracy is defined as the difference between OSI and CBCT (at 0° couch angle) measurement data. The measurement data with normal distribution were described as Mean ± SD. The data with non-normal distribution were expressed as M (Q). The difference of the former data was compared by one-way ANOVA, and the difference of the latter data was assessed by Kruskal-Wallis H nonparametric test. Results:For non-coplanarity, the translation accuracy of the phantom and the patient was ≤ 1.30 mm and ≤ 1.00 mm, and the rotation accuracy was ≤ 0.50° and ≤ 0.60°, respectively. The translation errors mainly occurred in the left-right and head-foot directions. In terms of stability, the maximum standard deviation of phantom coplanar translation and rotation was 0.06 mm and 0.06°. The maximum standard deviation of patient translation and rotation was 0.17 mm and 0.19°.Conclusions:Although the new SRS algorithm improves the non-coplanar accuracy, it still cannot meet the precise requirements of non-coplanar single isocenter radiotherapy for multiple brain metastases, especially in the left-right and head-foot directions. When the couch rotation angle is large, OSI is not recommended for image-guided radiotherapy. However, its high stability can be used to monitor the intrafractional motion of patients.
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Objective To compare the dosimetrics of the plan target volume (PTV) and organs at risk (OARs) between two treatment planning approaches for patients with multiple brain metastases from non-small cell lung cancer on CyberKnife.Methods 20 patients with multiple metastases from lung carcinoma were reviewed and analyzed,who had been treated by CyberKnife from December 2017 to December 2018.The CyberKnife stereotactic radiotherapy plans of the 20 cases were re-planed with single plan for multiple lesions and multiple plans per lesion.The dosimetry differences of PTV and OARs isodose disribution,conformity index (CI),total beam counts and total monitor units (MUs) were compared in the two types of plans.Results The two types of plans could satisfy over 95％ PTV coverage of the prescription dose.The maximum and mean dose of normal brain adjacent to the PTV were reduced in multiple plan approach effectively.Moreover,the maximum and mean dose of OARs (brainstem) dropped by 1.62％ and 5.57％ (t =1.09,P＜0.01) respectively.The number of treatment nodes and total MU declined by 4.63％ (t=1.87,P＜0.01) and 1.06％ in multiple plan approach,which could significantly shorten the clinical treatment time.The differences in CI index between these two types of plans was of no statistical significance.Conclusions For patients with multiple brain metastases of similar diameter and volume from non-small cell lung cancer to be treated on CyberKnife,multiple plans per lesion could not only reduce dose to normal brain tissue and OARs,but also improve the treatment efficiency.
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Objective@#To compare the dosimetrics of the plan target volume (PTV) and organs at risk (OARs) between two treatment planning approaches for patients with multiple brain metastases from non-small cell lung cancer on CyberKnife.@*Methods@#20 patients with multiple metastases from lung carcinoma were reviewed and analyzed, who had been treated by CyberKnife from December 2017 to December 2018. The CyberKnife stereotactic radiotherapy plans of the 20 cases were re-planed with single plan for multiple lesions and multiple plans per lesion. The dosimetry differences of PTV and OARs isodose disribution, conformity index (CI), total beam counts and total monitor units (MUs) were compared in the two types of plans.@*Results@#The two types of plans could satisfy over 95% PTV coverage of the prescription dose. The maximum and mean dose of normal brain adjacent to the PTV were reduced in multiple plan approach effectively. Moreover, the maximum and mean dose of OARs (brainstem) dropped by 1.62% and 5.57% (t=1.09, P<0.01) respectively. The number of treatment nodes and total MU declined by 4.63% (t=1.87, P<0.01)and 1.06% in multiple plan approach, which could significantly shorten the clinical treatment time. The differences in CI index between these two types of plans was of no statistical significance.@*Conclusions@#For patients with multiple brain metastases of similar diameter and volume from non-small cell lung cancer to be treated on CyberKnife, multiple plans per lesion could not only reduce dose to normal brain tissue and OARs, but also improve the treatment efficiency.
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Objective To study the analysis of non-small cell lung cancer patients with multiple brain metastases with erlotinib combined with whole brain radiation therapy clinical observation and effect of C on vascular endothelial growth factor level. Methods 40 cases of non - small cell lung cancer patients with multiple brain metastases treated in Taizhou tumor hospital from January 2015 to April 2016 were selected and randomly divided into the control group and the experimental group, with 20 patients in each group. The control group and the experimental group patients were given clinical treatment of whole brain radiotherapy, the control group was given routine treatment, the experimental group received erlotinib. The clinical effects of the 2 groups were compared and analyzed. Results After the corresponding treatment, the experimental group of 20 patients, 8 cases of complete remission, 7 cases of partial remission, the number of effective treatment for 15 cases, the treatment rate was 75.0％. Of the patients in the control group, 6patients had complete remission, and 4 patients had partial remission. The effective rate was 50％. Available, the effective rate of the treatment group (75.0％) was significantly higher than that of the control group (50.0％), with statistical difference (P<0.05). The survival rate of the experimental group after one year (80.0％) was significantly higher than that of the control group (60.0％), with statistical difference (P<0.05). The level of vascular endothelial growth factor (C) in the experimental group was significantly lower than that in the control group (P<0.05). Conclusion Non small cell lung cancer patients with multiple brain metastases with erlotinib combined with radiotherapy in the clinical treatment effect of whole brain is better, can improve the survival rate in a large extent, improve the endothelial growth factor C levels, with the further promotion of the clinical significance.
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PURPOSE: To determine feasibility of RapidArc in sequential or simultaneous integrated tumor boost in whole brain radiation therapy (WBRT) for poor prognostic patients with four or more brain metastases. MATERIALS AND METHODS: Nine patients with multiple (> or =4) brain metastases were analyzed. Three patients were classified as class II in recursive partitioning analysis and 6 were class III. The class III patients presented with hemiparesis, cognitive deficit, or apraxia. The ratio of tumor to whole brain volume was 0.8-7.9%. Six patients received 2-dimensional bilateral WBRT, (30 Gy/10-12 fractions), followed by sequential RapidArc tumor boost (15-30 Gy/4-10 fractions). Three patients received RapidArc WBRT with simultaneous integrated boost to tumors (48-50 Gy) in 10-20 fractions. RESULTS: The median biologically effective dose to metastatic tumors was 68.1 Gy10 and 67.2 Gy10 and the median brain volume irradiated more than 100 Gy3 were 1.9% (24 cm3) and 0.8% (13 cm3) for each group. With less than 3 minutes of treatment time, RapidArc was easily applied to the patients with poor performance status. The follow-up period was 0.3-16.5 months. Tumor responses among the 6 patients who underwent follow-up magnetic resonance imaging were partial and stable in 3 and 3, respectively. Overall survival at 6 and 12 months were 66.7% and 41.7%, respectively. The local progression-free survival at 6 and 12 months were 100% and 62.5%, respectively. CONCLUSION: RapidArc as a component in whole brain radiation therapy for poor prognostic, multiple brain metastases is an effective and safe modality with easy application.
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Humans , Apraxias , Brain , Disease-Free Survival , Follow-Up Studies , Magnetic Resonance Imaging , Neoplasm Metastasis , Paresis , Radiotherapy, Intensity-ModulatedABSTRACT
PURPOSE: This study was a retrospective evaluation of the efficacy of stereotactic radiosurgery (SRS) in patients with >4 metastases to the brain. MATERIALS AND METHODS: Between January 2004 and December 2006, 68 patients with > or = 4 multiple brain metastases were included and reviewed retrospectively. Twenty-nine patients received SRS and 39 patients received whole brain radiotherapy (WBRT). Patients with small cell lung cancers and melanomas were excluded. The primary lesions were non-small cell lung cancer (69.0%) and breast cancer (13.8%) in the SRS group and non-small cell lung cancer (64.1%), breast cancer (15.4%), colorectal cancer (12.8%), esophageal cancer (5.1%) in the WBRT group. SRS involved gamma-knife radiosurgery and delivered 10~20 Gy (median, 16 Gy) in a single fraction with a 50% marginal dose. WBRT was delivered daily in 3 Gy fractions, for a total of 30 Gy. After completion of treatment, a follow-up brain MRI or a contrast-enhanced brain CT was reviewed. The overall survival and intracranial progression-free survival were compared in each group. RESULTS: The median follow-up period was 5 months (range, 2~19 months) in the SRS group and 6 months (range, 4~23 months) in the WBRT group. The mean number of metastatic lesions in the SRS and WBRT groups was 6 and 5, respectively. The intracranial progression-free survival and overall survival in the SRS group was 5.1 and 5.6 months, respectively, in comparison to 6.1 and 7.2 months, respectively, in the WBRT group. CONCLUSION: SRS was less effective than WBRT in the treatment of patients with >4 metastases to the brain.
Subject(s)
Humans , Brain , Breast Neoplasms , Carcinoma, Non-Small-Cell Lung , Colorectal Neoplasms , Disease-Free Survival , Esophageal Neoplasms , Follow-Up Studies , Lung Neoplasms , Melanoma , Neoplasm Metastasis , Radiosurgery , Retrospective StudiesABSTRACT
OBJECTIVE: This study is performed to evaluate the role of gamma knife radiosurgery(GKS) for treatment of patients with large number of metastatic brain lesions. METHODS: The authors retrospectively reviewed the clinical outcome of 99 patients who underwent 124 GKS procedures for a total of 564 metastatic lesions. Sixty-three patients presented with 1 to 3 lesions (group A) and 36 patients presented with 4 or more lesions (group B) at initial GKS. The authors assessed survival according to a variety of possible prognostic factors. RESULTS: Median survival from the GKS for all cases was 28 weeks. The recursive partitioning analysis (RPA) class (p<0.0001) and the total tumor volume (p=0.0174) were significant factors influencing survival. The number of lesions, whole brain radiotherapy, primary tumor site, age, and sex were not significant. Median survival of group A (28 weeks) was not different from that of group B (28 weeks) (p=0.4027). Median survival was 66, 28, and 13 weeks for RPA class I, II, and III respectively in group A and 44, 36, and 11 weeks in group B. CONCLUSION: It is suggested that GKS provides a survival gain even in patients with a large number (4 or more) of metastatic lesions. Concerning the survival and the selection of patients for radiosurgery, RPA class and the total tumor volume should be considered as more important factors than the number of lesions. Multiplicity of the lesions alone should not be a factor for contraindication of radiosurgery.