Objective: To investigate the clinical diagnostic value of peripheral lung cancer using multi-slice CT (MSCT) perfu- sion imaging and the relationship with microvessel density (MVD). Methods: 38 patients with pulmonar...Objective: To investigate the clinical diagnostic value of peripheral lung cancer using multi-slice CT (MSCT) perfu- sion imaging and the relationship with microvessel density (MVD). Methods: 38 patients with pulmonary masses proved by pathology including 25 cases of peripheral lung cancer and 13 cases of benign masses were studied prospectively with GE Lightspeed Qx/I plus 16-slice helical CT perfusion imaging, and 25 patients with lung cancer were comparative studied with its MVD calculated using LSAB. With the CT perfusion 2-body tumor software, the parameters of CT perfusion including blood value (BV), blood flow (BF), mean transit time (MTT) and permeability surface (PS) were analyzed. Results: The four param- eter values in lung cancer were all higher than that in pulmonary benign masses, and there were significant differences among BV, MTT and PS (P<0.05), especially in BV (P<0.01). The MVD value of lung cancer was higher than that of pulmonary benign masses (P<0.05), and the MVD of adenocarcinoma was higher than that of squamous cell carcinoma (P<0.05). In 25 cases with lung cancer, there was positive correlation only between BV and MVD value (r=0.852, P<0.01). Conclusion: It is helpful to diagnose the peripheral lung cancer with MSCT perfusion imaging and to differentiate from pulmonary benign masses, its bases are MVD pathologically.展开更多
The most crucial requirement in radiation therapy treatment planning is a fast and accurate treatment planning system that minimizes damage to healthy tissues surrounding cancer cells. The use of Monte Carlo toolkits ...The most crucial requirement in radiation therapy treatment planning is a fast and accurate treatment planning system that minimizes damage to healthy tissues surrounding cancer cells. The use of Monte Carlo toolkits has become indispensable for research aimed at precisely determining the dose in radiotherapy. Among the numerous algorithms developed in recent years, the GAMOS code, which utilizes the Geant4 toolkit for Monte Carlo simula-tions, incorporates various electromagnetic physics models and multiple scattering models for simulating particle interactions with matter. This makes it a valuable tool for dose calculations in medical applications and throughout the patient’s volume. The aim of this present work aims to vali-date the GAMOS code for the simulation of a 6 MV photon-beam output from the Elekta Synergy Agility linear accelerator. The simulation involves mod-eling the major components of the accelerator head and the interactions of the radiation beam with a homogeneous water phantom and particle information was collected following the modeling of the phase space. This space was po-sitioned under the X and Y jaws, utilizing three electromagnetic physics mod-els of the GAMOS code: Standard, Penelope, and Low-Energy, along with three multiple scattering models: Goudsmit-Saunderson, Urban, and Wentzel-VI. The obtained phase space file was used as a particle source to simulate dose distributions (depth-dose and dose profile) for field sizes of 5 × 5 cm<sup>2</sup> and 10 × 10 cm<sup>2</sup> at depths of 10 cm and 20 cm in a water phantom, with a source-surface distance (SSD) of 90 cm from the target. We compared the three electromagnetic physics models and the three multiple scattering mod-els of the GAMOS code to experimental results. Validation of our results was performed using the gamma index, with an acceptability criterion of 3% for the dose difference (DD) and 3 mm for the distance-to-agreement (DTA). We achieved agreements of 94% and 96%, respectively, between simulation and experimentation for the three electromagnetic physics models and three mul-tiple scattering models, for field sizes of 5 × 5 cm<sup>2</sup> and 10 × 10 cm<sup>2</sup> for depth-dose curves. For dose profile curves, a good agreement of 100% was found between simulation and experimentation for the three electromagnetic physics models, as well as for the three multiple scattering models for a field size of 5 × 5 cm<sup>2</sup> at 10 cm and 20 cm depths. For a field size of 10 × 10 cm<sup>2</sup>, the Penelope model dominated with 98% for 10 cm, along with the three multiple scattering models. The Penelope model and the Standard model, along with the three multiple scattering models, dominated with 100% for 20 cm. Our study, which compared these different GAMOS code models, can be crucial for enhancing the accuracy and quality of radiotherapy, contributing to more effective patient treatment. Our research compares various electro-magnetic physics models and multiple scattering models with experimental measurements, enabling us to choose the models that produce the most reli-able results, thereby directly impacting the quality of simulations. This en-hances confidence in using these models for treatment planning. Our re-search consistently contributes to the progress of Monte Carlo simulation techniques in radiation therapy, enriching the scientific literature.展开更多
BACKGROUND Lung cancer(LC)is the leading cause of morbidity and mortality among malignant neoplasms.Improving the diagnosis and treatment of LC remains an urgent task of modern oncology.Previously,we established that ...BACKGROUND Lung cancer(LC)is the leading cause of morbidity and mortality among malignant neoplasms.Improving the diagnosis and treatment of LC remains an urgent task of modern oncology.Previously,we established that in gastric,breast and cervical cancer,tumor microvessels(MVs)differ in morphology and have different prognostic significance.The connection between different types of tumor MVs and the progression of LC is not well understood.AIM To evaluate the morphological features and clinical significance of tumor MVs in lung squamous cell carcinoma(LUSC).METHODS A single-center retrospective cohort study examined medical records and archival paraffin blocks of 62 and 180 patients with stage I-IIIA LUSC in the training and main cohorts,respectively.All patients underwent radical surgery(R0)at the Orenburg Regional Cancer Clinic from May/20/2009 to December/14/2021.Tumor sections were routinely processed,and routine Mayer's hematoxylin and eosin staining and immunohistochemical staining for cluster of differentiation 34(CD34),podoplanin,Snail and hypoxia-inducible factor-1 alpha were performed.The morphological features of different types of tumor MVs,tumor parenchyma and stroma were studied according to clinicopathological characteristics and LUSC prognosis.Statistical analysis was performed using Statistica 10.0 software.Univariate and multivariate logistic regression analyses were performed to identify potential risk factors for LUSC metastasis to regional lymph nodes(RLNs)and disease recurrence.Receiver operating characteristic curves were constructed to discriminate between patients with and without metastases in RLNs and those with and without disease recurrence.The effectiveness of the predictive models was assessed by the area under the curve.Survival was analyzed using the Kaplan-Meier method.The log-rank test was used to compare survival curves between patient subgroups.A value of P<0.05 was considered to indicate statistical significance.RESULTS Depending on the morphology,we classified tumor vessels into the following types:normal MVs,dilated capillaries(DCs),atypical DCs,DCs with weak expression of CD34,"contact-type"DCs,structures with partial endothelial linings,capillaries in the tumor solid component and lymphatic vessels in lymphoid and polymorphocellular infiltrates.We also evaluated the presence of loose,fine fibrous connective tissue(LFFCT)and retraction clefts in the tumor stroma,tumor spread into the alveolar air spaces(AASs)and fragmentation of the tumor solid component.According to multivariate analysis,the independent predictors of LUSC metastasis in RLNs were central tumor location(P<0.00001),the presence of retraction clefts(P=0.003),capillaries in the tumor solid component(P=0.023)and fragmentation in the tumor solid component(P=0.009),whereas the independent predictors of LUSC recurrence were tumor grade 3(G3)(P=0.001),stage N2(P=0.016),the presence of LFFCT in the tumor stroma(P<0.00001),fragmentation of the tumor solid component(P=0.0001),and the absence of tumor spread through the AASs(P=0.0083).CONCLUSION The results obtained confirm the correctness of our previously proposed classification of different types of tumor vessels and may contribute to improving the diagnosis and treatment of LUSC.展开更多
以青海省海西州乌兰县某测区为实验区,利用SfM-MVS(Structure from Motion with Multi-view Stereo)技术对无人机航摄数据进行处理,分析了不同控制点布设方案下的数据处理精度,完成了测区高质量三维点云数据的获取和DEM构建。结果表明:...以青海省海西州乌兰县某测区为实验区,利用SfM-MVS(Structure from Motion with Multi-view Stereo)技术对无人机航摄数据进行处理,分析了不同控制点布设方案下的数据处理精度,完成了测区高质量三维点云数据的获取和DEM构建。结果表明:采用SfM-MVS技术处理数据能够满足实验区设计测图精度要求,该方法在高山地区大比例尺地形图测绘方面具有可行性。展开更多
基金Supported by a grant from the Scientific Research Foundation of the Educational Department of Liaoning province (No. 20272277).
文摘Objective: To investigate the clinical diagnostic value of peripheral lung cancer using multi-slice CT (MSCT) perfu- sion imaging and the relationship with microvessel density (MVD). Methods: 38 patients with pulmonary masses proved by pathology including 25 cases of peripheral lung cancer and 13 cases of benign masses were studied prospectively with GE Lightspeed Qx/I plus 16-slice helical CT perfusion imaging, and 25 patients with lung cancer were comparative studied with its MVD calculated using LSAB. With the CT perfusion 2-body tumor software, the parameters of CT perfusion including blood value (BV), blood flow (BF), mean transit time (MTT) and permeability surface (PS) were analyzed. Results: The four param- eter values in lung cancer were all higher than that in pulmonary benign masses, and there were significant differences among BV, MTT and PS (P<0.05), especially in BV (P<0.01). The MVD value of lung cancer was higher than that of pulmonary benign masses (P<0.05), and the MVD of adenocarcinoma was higher than that of squamous cell carcinoma (P<0.05). In 25 cases with lung cancer, there was positive correlation only between BV and MVD value (r=0.852, P<0.01). Conclusion: It is helpful to diagnose the peripheral lung cancer with MSCT perfusion imaging and to differentiate from pulmonary benign masses, its bases are MVD pathologically.
文摘The most crucial requirement in radiation therapy treatment planning is a fast and accurate treatment planning system that minimizes damage to healthy tissues surrounding cancer cells. The use of Monte Carlo toolkits has become indispensable for research aimed at precisely determining the dose in radiotherapy. Among the numerous algorithms developed in recent years, the GAMOS code, which utilizes the Geant4 toolkit for Monte Carlo simula-tions, incorporates various electromagnetic physics models and multiple scattering models for simulating particle interactions with matter. This makes it a valuable tool for dose calculations in medical applications and throughout the patient’s volume. The aim of this present work aims to vali-date the GAMOS code for the simulation of a 6 MV photon-beam output from the Elekta Synergy Agility linear accelerator. The simulation involves mod-eling the major components of the accelerator head and the interactions of the radiation beam with a homogeneous water phantom and particle information was collected following the modeling of the phase space. This space was po-sitioned under the X and Y jaws, utilizing three electromagnetic physics mod-els of the GAMOS code: Standard, Penelope, and Low-Energy, along with three multiple scattering models: Goudsmit-Saunderson, Urban, and Wentzel-VI. The obtained phase space file was used as a particle source to simulate dose distributions (depth-dose and dose profile) for field sizes of 5 × 5 cm<sup>2</sup> and 10 × 10 cm<sup>2</sup> at depths of 10 cm and 20 cm in a water phantom, with a source-surface distance (SSD) of 90 cm from the target. We compared the three electromagnetic physics models and the three multiple scattering mod-els of the GAMOS code to experimental results. Validation of our results was performed using the gamma index, with an acceptability criterion of 3% for the dose difference (DD) and 3 mm for the distance-to-agreement (DTA). We achieved agreements of 94% and 96%, respectively, between simulation and experimentation for the three electromagnetic physics models and three mul-tiple scattering models, for field sizes of 5 × 5 cm<sup>2</sup> and 10 × 10 cm<sup>2</sup> for depth-dose curves. For dose profile curves, a good agreement of 100% was found between simulation and experimentation for the three electromagnetic physics models, as well as for the three multiple scattering models for a field size of 5 × 5 cm<sup>2</sup> at 10 cm and 20 cm depths. For a field size of 10 × 10 cm<sup>2</sup>, the Penelope model dominated with 98% for 10 cm, along with the three multiple scattering models. The Penelope model and the Standard model, along with the three multiple scattering models, dominated with 100% for 20 cm. Our study, which compared these different GAMOS code models, can be crucial for enhancing the accuracy and quality of radiotherapy, contributing to more effective patient treatment. Our research compares various electro-magnetic physics models and multiple scattering models with experimental measurements, enabling us to choose the models that produce the most reli-able results, thereby directly impacting the quality of simulations. This en-hances confidence in using these models for treatment planning. Our re-search consistently contributes to the progress of Monte Carlo simulation techniques in radiation therapy, enriching the scientific literature.
文摘BACKGROUND Lung cancer(LC)is the leading cause of morbidity and mortality among malignant neoplasms.Improving the diagnosis and treatment of LC remains an urgent task of modern oncology.Previously,we established that in gastric,breast and cervical cancer,tumor microvessels(MVs)differ in morphology and have different prognostic significance.The connection between different types of tumor MVs and the progression of LC is not well understood.AIM To evaluate the morphological features and clinical significance of tumor MVs in lung squamous cell carcinoma(LUSC).METHODS A single-center retrospective cohort study examined medical records and archival paraffin blocks of 62 and 180 patients with stage I-IIIA LUSC in the training and main cohorts,respectively.All patients underwent radical surgery(R0)at the Orenburg Regional Cancer Clinic from May/20/2009 to December/14/2021.Tumor sections were routinely processed,and routine Mayer's hematoxylin and eosin staining and immunohistochemical staining for cluster of differentiation 34(CD34),podoplanin,Snail and hypoxia-inducible factor-1 alpha were performed.The morphological features of different types of tumor MVs,tumor parenchyma and stroma were studied according to clinicopathological characteristics and LUSC prognosis.Statistical analysis was performed using Statistica 10.0 software.Univariate and multivariate logistic regression analyses were performed to identify potential risk factors for LUSC metastasis to regional lymph nodes(RLNs)and disease recurrence.Receiver operating characteristic curves were constructed to discriminate between patients with and without metastases in RLNs and those with and without disease recurrence.The effectiveness of the predictive models was assessed by the area under the curve.Survival was analyzed using the Kaplan-Meier method.The log-rank test was used to compare survival curves between patient subgroups.A value of P<0.05 was considered to indicate statistical significance.RESULTS Depending on the morphology,we classified tumor vessels into the following types:normal MVs,dilated capillaries(DCs),atypical DCs,DCs with weak expression of CD34,"contact-type"DCs,structures with partial endothelial linings,capillaries in the tumor solid component and lymphatic vessels in lymphoid and polymorphocellular infiltrates.We also evaluated the presence of loose,fine fibrous connective tissue(LFFCT)and retraction clefts in the tumor stroma,tumor spread into the alveolar air spaces(AASs)and fragmentation of the tumor solid component.According to multivariate analysis,the independent predictors of LUSC metastasis in RLNs were central tumor location(P<0.00001),the presence of retraction clefts(P=0.003),capillaries in the tumor solid component(P=0.023)and fragmentation in the tumor solid component(P=0.009),whereas the independent predictors of LUSC recurrence were tumor grade 3(G3)(P=0.001),stage N2(P=0.016),the presence of LFFCT in the tumor stroma(P<0.00001),fragmentation of the tumor solid component(P=0.0001),and the absence of tumor spread through the AASs(P=0.0083).CONCLUSION The results obtained confirm the correctness of our previously proposed classification of different types of tumor vessels and may contribute to improving the diagnosis and treatment of LUSC.
文摘以青海省海西州乌兰县某测区为实验区,利用SfM-MVS(Structure from Motion with Multi-view Stereo)技术对无人机航摄数据进行处理,分析了不同控制点布设方案下的数据处理精度,完成了测区高质量三维点云数据的获取和DEM构建。结果表明:采用SfM-MVS技术处理数据能够满足实验区设计测图精度要求,该方法在高山地区大比例尺地形图测绘方面具有可行性。