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Objective:To analyze the failure patterns and influencing factors of stereotactic ablative radiotherapy (SABR) for early-stage non-small cell lung cancer (ES-NSCLC).Methods:113 cases of ES-NSCLC treated with SABR from 2012 to 2020 in our hospital were retrospectively analyzed. The failure patterns, recurrence time, recurrence site and influencing factors were analyzed. Kaplan-Meier method was used to calculate the local recurrence rate, regional lymph node recurrence rate and distant metastasis rate. Univariate analysis was performed by Log-rank test, and multivariate analysis was performed by Cox model.Results:The median follow-up time was 58 months (range: 6-108 months), and a total of 45 patients (39.8%) recurred. The median recurrence time was 36 months. Distant metastasis (DM) occurred in 31 patients (27.4%) and DM alone in 24 patients (21.2%). Local recurrence (LR) was developed in 12 patients (10.6%) and LR alone in 7(6.2%). Regional lymph node recurrence (RR) occurred in 11 patients (9.7%) and RR alone in 6 patients (5.3%). LR combined with RR was observed in 1 case (0.9%), LR combined with DM in 3(2.7%), LR combined with RR and DM in 1(0.9%), and RR combined with DM in 3(2.7%). The 1-, 2-, 3-, 4-and 5-year recurrence rates were 5.4%, 16.6%, 27.5%, 44% and 51.2%, respectively. Univariate and multivariate analyses suggested that EGFR mutation was an influencing factor of high recurrence rate.Conclusion:ES-NSCLC patients treated with SABR alone have a high recurrence rate, and DM is the most common mode of failure. Follow-up consolidation therapy is recommended, especially for EGFR mutation-positive NSCLC patients.
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Objective:To propose an automatic planning approach for Eclipse15.6 planning system based on Eclipse scripting application programming interface (ESAPI) and evaluate its clinical application.Methods:20 patients with nasopharyngeal carcinoma and 20 cases of rectal cancer were selected in the clinical planning. The developed automatic planning script SmartPlan and RapidPlan were used for automatic planning and dosimetric parameters were compared with manual planning. The differences were compared between two groups by using Wilcoxon signed rank test. Results:The dosimetric results of automatic and manual plans could meet clinical requirements. There was no significant difference in target coverage in nasopharyngeal carcinoma planning between two groups ( P>0.05), and automatic plans were superior to manual plans in organs at risk sparing ( P<0.05). Except for the homogeneity index of PTV and the maximum dose of bowel in rectal cancer plans, the other dosimetric parameters of the automatic plans were better than those of the manual plans (all P<0.05). Conclusions:Compared with the manual plans, the automatic plans have the same or similar target coverage, similar or better protection of organs at risk, and more convenient implementation. The developed SmartPlan based on ESAPI has clinical feasibility and effectiveness.
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Objective:To develop a verification platform based on Monte Carlo (MC) for independent dose verification of volumetric modulated arc therapy (VMAT) plans.Methods:The head model including collimator of Varian TrueBeam linear accelerator was constructed by using EGSnrc/BEAMnrc, and the independent dose verification platform for the patients’ VMAT plans was built based on the head model and an in-house code. The percent depth dose (PDD) curves and off-axis ratios for different field sizes, the dose distribution of two irregular fields and three VMAT plans of the head and neck, chest, and pelvis were simulated using the platform. The simulated results of the PDD curves and the off-axis ratios of different field sizes were compared with the blue water measurement results. The difference between the irregular fields and the actual ArcCHECK measurements was also investigated. Besides, the differences among the MC simulated dose, TPS calculated dose and the ArcCHECK measured dose were analyzed by several methods, such as γ analysis and dose-volume histogram to verify whether the platform could be independently employed for dose verification.Results:The MC simulated results of PDD curves and off-axis ratios from 4 cm×4 cm to 40 cm×40 cm were in good agreement with the measured results. And the γ passing rates between the MC simulation and the ArcCHECK measurement for the irregular fields were above 98.1% and 99.1% for 3%/2 mm and 3%/3 mm, respectively. For VMAT plans of three patients, the γ results between the MC simulated dose and ArcCHECK measured dose were better than 93.8% and 95.9% under the criteria of 3%/2 mm and 3%/3 mm respectively. At the same time, the γ passing rates of nasopharyngeal, lung, and rectal cancers were 95.2%, 98.6% and 98.9% based on 3D γ analysis using TPS calculated dose and MC simulated dose under the criteria of 3%/3 mm; the passing rates of these three were 90.3%, 95.1% and 96.7% for 3%/2 mm, respectively.Conclusions:The simulation results of the MC-based verification platform developed in this study show a good agreement with the actual measurement results, and the simulation results are closer to the real dose distribution using the patients’ data. The preliminary results demonstrate that the platform can be used for accurate independent dose verification of VMAT plans.
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Objective:To propose an automatic planning method of intensity-modulated radiotherapy (IMRT) for esophageal cancer based on dose volume histogram prediction and beam angle optimization in Raystation treatment planning system.Methods:50 IMRT plans of esophageal cancer were selected as the training set to establish a dose prediction model for organs at risk. Another 20 testing plans were optimized in Raystation using RuiPlan and manual method, and the beam angle optimization and dose volume histogram prediction functions of RuiPlan were used for automatic planning. Dosimetric differences and planning efficiency between two methods were statistically compared with paired t-test. Results:There were no significant dosimetric differences in the conformity index (CI), homogeneity index (HI) of PTV, V 5Gy of both lungs and D max of the spinal cord between automatic and manual plans (all P>0.05). Compared with those in the manual plans, the V 20Gy and D mean of the left and right lungs generated from automatic plans were reduced by 1.1%, 0.37 Gy and 1.2%, 0.38 Gy (all P<0.05), and the V 30Gy, V 40Gy and D mean of the heart in automatic plans were significantly decreased by 5.1%, 3.0% and 1.41 Gy, respectively (all P<0.05). The labor time, computer working time, and monitor unit (MU) number of automatic plans were significantly decreased by 65.8%, 14.1%, and 17.2%, respectively (all P<0.05). Conclusion:RuiPlan automatic planning scripts can improve the efficiency of esophageal cancer planning by dose prediction and beam angle optimization, providing an alternative for esophageal cancer radiotherapy planning.
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Objective:To build a systemic and automatic importing scheme for importing CT images and structures into the treatment planning systems (TPSs) of Eclipse and Monaco.Methods:Based on two TPSs of Eclipse and Monaco, the files of CT images and structures were automatically transported from OAR auto-delineation system to the importing directory of these two TPSs using batch script in Windows system. Following the standard importing procedures of these two TPSs, the automatically importing script of CT images and structures were developed using the application of UiBot. Finally, the CT images and structures were imported into these two TPSs opportunely.Results:By comparing the importing time using script and manual methods, the script not only achieved auto-importing CT images and structures into TPSs, but also yielded almost the same efficiency to manual method. The number of imaging layers in most patients was between 130 and 180, and the average manual and automatic importing time within this interval was 76 s and 75 s.Conclusions:Automatic scripts can be developed by using the automation function of UiBot combined with the actual problems of radiotherapy and repeated workflow. The efficiency of radiotherapy work can be significantly improved. Manual and time costs can be saved. It provides a novel alternative for the automation of radiotherapy procedures.
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Objective:To validate the accuracy of physical model of in-vivo 3D dose verification based on electronic portal imaging device (EPID) using the phantom and preliminarily analyze the clinical application.Methods:Two phantoms (uniform and non-uniform phantoms) were involved in this study. The system of in-vivo 3D dose verification based on EPID was employed to acquire the images of square fields (SF) and combined fields of intensity-modulated radiotherapy (CFIMRT). The physical model of different media was constructed using the system. The factor of γ passing rate under different dose/distance criteria was statistically compared. For clinical cases, the dose-volume histograms were adopted to analyze the dose distribution of target volume and organs at risk (OARs).Results:For the SF in the uniform phantom, the average γ passing rate (3%/3 mm) was (97.49±1.11)%, and (94.06±5.11)% for the SF in the non-uniform phantom ( P>0.05). No statistical significance was noted in IMRT using different delivery methods (all P>0.05). For clinical cases, the average γ passing rate (3%/2 mm) was (97.96±1.84)% in the pre-treatment dose verification, and (90.51±6.96)%(3%/3 mm) for the in-vivo 3D dose verification. For clinical cases, significant dose deviation was observed in OARs with small size and large volume changes. Conclusion:The in-vivo 3D dose verification model based on EPID can be effectively applied in inter-fraction dose verification, providing technical support for adaptive radiotherapy in clinical practice.
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Objective:To explore the value of BLADE sequence in determining the target range of esophageal cancer radiotherapy through the correlation and consistency between measured esophageal cancer length on the MRI-BLADE sequence and the surgical pathological specimens.Methods:Clinical data of 36 patients who were pathologically diagnosed with esophageal carcinoma and received preoperative esophageal MRI in the Affiliated Cancer Hospital of Zhengzhou University between January 2016 to June 2019 were collected. The CT, DWI and BLADE sequence images of all participants were collected and imported into the Monaco system, by which the correlation and consistency between the tumor length measured based on these three imaging methods were statistically compared. Furthermore, the differences in gross tumor volume (GTV) delineated by different physicians in different images were compared.Results:The correlation coefficients of the tumor length measured by CT, DWI and BLADE and pathological specimen length were 0.467, 0.723 and 0.896, respectively. The consistency analysis indicated that all the differences between the BLADE sequence and pathological specimen length were within the 95% consistency limit. The consistency and correlation between the BLADE sequence and actual tumor length were significantly better than those between the DWI sequence and CT images (both P<0.05). The volume of DWI and BLADE images obtained by four physicians was significantly smaller than that of CT images (both P<0.05). The differences in GTV delineated by different physicians by these three imaging methods were insignificant (all P>0.05), but the GTV delineated by the four physicians on the BLADE sequence were more similar (all P>0.05). Conclusions:BLADE sequence can help physicians to determine the upper and lower boundaries of esophageal tumors more accurately and reduce the differences in GTV delineation among different physicians. And it can effectively improve the unity of individual′s understanding of the scope of target area delineation, and improve the objectivity of clinicians′ judgment of GTV. BLADE sequence can be used as an important imaging tool for accurate target delineation in radiotherapy.
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As a method for local treatment, radiotherapy plays a key role in the management of tumors. In the past few decades, great progress has been made in radiotherapy technology, with improvements in conformity, homogeneity, and radiotherapy efficiency, and the results are encouraging. Nevertheless, the maximum tolerated dose of normal tissue has limited the further increase in radiotherapy dose in the tumor area. If radiation-induced toxicities can be reduced, a higher radiotherapy dose can be delivered to tumor tissue, so as to achieve a better treatment response. In recent years, the unique FLASH effect of ultra-high-dose-rate radiotherapy (FLASH-RT) is capable of maintaining a consistent tumor response whilst reducing radiation-induced toxicities in normal tissue, and therefore, FLASH-RT has become a research hotspot in the field of radiotherapy across the world. At present, some scholars tend to explain the FLASH effect using the theory of acute oxygen depletion, but the protective effect of FLASH-RT on normal tissue remains to be clarified. In addition, preliminary clinical studies have been conducted for FLASH-RT, and the results are promising. Based on existing evidence, this article elaborates on the research advances in FLASH-RT in the treatment of malignant tumor, so as to provide a reference for the translation and application of this new technique.
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Objective:To explore a new technology that can protect the lungs and heart better by utilizing the dose distribution attributes of the half-field and the characteristics of the VMAT (volumetric modulated arc therapy) technology.Methods:A three-dimensional water tank was used to measure the dose of symmetrical field and half field edge and analyze them comparatively. A total of 50 patients with left breast cancer receiving the postoperative radiotherapy were selected. Among them, 25 patients were performed conserving surgery and 25 patients were performed radical mastectomy. After the operation, all the patients received the prescription dose of 50 Gy in 25 fractions. Based on the Eclipse system, the symmetrical field continuous arc VMAT technology and the semi-field segmented arc VMAT technology were used to design the plan. Besides, the dose suitability data and the treatment efficiency of target areas and organs at risk were compared and analyzed.Results:The radiation size of half-field did not increase with the increased depth in the water mode. The symmetric field gradually enlarged due to the angle of tensor factor, increased to about 2 cm at the depth of 30 cm, and the delivery dose in the half-field was lower than that in the symmetric field. The closer the field edge is, the more obvious it is. Compared with the symmetric field continuous arc plan, the half-field segmental arc VMAT plan significantly improved the delivery dose of the lungs and heart ( t=-4.11, -4.42, P=0.00), in which the mean values of V5, V30, and Dmean for the whole structure of the heart were reduced by 52.5%, 65.5%, and 47%, respectively. The left anterior descending coronary artery, which was closely related to the target area, had a decrease of more than 20%. The mean values of V5, V10, V20, and Dmean of the affected lung were reduced by 21.6%, 24.8%, 25.0%, and 23.2%, respectively. The mean values of the doses of other endangered healthy organs, and the execution time of half-field segment arc plan were also better than the continuous arc plan. Conclusions:For breast cancer radiotherapy, the combination of half-field and VMAT can give full play to the advantages of half-field and VMAT, and significantly reduce the irradiated dose of the heart, affected lung, and healthy side of the breast.
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Objective: To evaluate the anti-inflammatory activity of Crotalaria ferruginea extract (CFE) and its mechanism. Methods: An intratracheal lipopolysaccharide (LPS) instillation-induced acute lung injury (ALI) model was used to study the anti-inflammatory activity of CFE in vivo. The LPS-induced shock model was used to analyze the effect of CFE on survival. LPS-stimulated RAW264.7 cell model was used to investigate the anti-inflammatory activity of CFE in vitro and the effects on mitogen-Activated protein kinase (MAPK) or nuclear factor-κB (NF-κB) signaling pathways. Results: CFE administration decreased the number of inflammatory cells, reduced the levels of tumor necrosis factor-α (TNF-A), monocyte chemotactic protein-1 (MCP-1), interleukin-6 (IL-6), and interferon-γ, and diminished protein content in the bronchoalveolar lavage fluid of mice. CFE also reduced lung wet-To-dry weight ratio, myeloperoxidase, and lung tissue pathological injury. CFE pre-Administration improved the survival rate of mice challenged with a lethal dose of LPS. CFE reduced LPS-Activated RAW264.7 cells to produce nitric oxide, TNF-α, MCP-1, and IL-6. Furthermore, CFE inhibited nuclear translocation and phosphorylation of NF-κB P65, extracellular signal-regulated kinase, c-Jun N-Terminal kinases, and P38 MAPKs. Conclusions: CFE exhibits potent anti-inflammatory activity in LPS-induced ALI mice, LPS-shock mice, and RAW264.7 cells, and its mechanism may be associated with the inhibition of NF-κB and MAPK signaling pathways. Crotalaria ferruginea may be a useful therapeutic drug for the treatment of ALI and other respiratory inflammations.
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Objective:To evaluate the value and identify the prognosic factors of postoperative radiotherapy (PORT) in completely resected stage Ⅲ(pN 2) lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) wild-type who received adjuvant chemotherapy. Methods:Clinical data of 172 patients with stage Ⅲ(pN 2) EGFR wild-type lung adenocarcinoma who underwent radical resection and adjuvant chemotherapy from 2009 to 2016 were retrospectively analyzed. All patients received platinum-based adjuvant chemotherapy combining two drugs for>4 cycles, and divided into the PORT group and the non-PORT group. The survival rate was calculated by Kaplan- Meier method and log-rank test, and multivariate prognostic analysis was performed by Cox’s regression model. Results:Among 172 patients, the median overall survival (OS), 3-year and 5-year OS rates were 40 months, 55.9% and 28.3%, respectively. The median disease-free survival (DFS), 3-year and 5-year DFS rates were 17 months, 24.5% and 13.0%, respectively. DFS was significantly improved in the PORT group (29 months vs. 13 months, P=0.001), whereas OS did not significantly differ between two groups (51 months vs. 38 months, P=0.151). In subgroup analysis, DFS of patients with multistation N 2 or the number of N 2 metastases of≥3 or skip N 2 in the PORT group was significantly longer ( P<0.05), whereas PORT exerted no significant effect on OS ( P>0.05). Conclusions:For patients with completely resected stage Ⅲ(N 2) EGFR wild-type lung adenocarcinoma receiving adjuvant chemotherapy, PORT might increase DFS and have a trend toward longer OS. However, these findings remain to be validated by large sample size investigations.
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Objective:To investigate whether radiotherapy should be delivered before the application of immune checkpoint inhibitor PD-1 in patients with advanced non-small cell lung cancer (NSCLC) and evaluate the effect of previous radiotherapy on the efficacy and pulmonary toxicity of PD-1 inhibitor.Methods:Clinical data of patients with stage Ⅳ NSCLC who received immunotherapy in Henan Cancer Hospital from March 2015 to September 2019 were retrospectively analyzed. The baseline data of patients, the status of radiotherapy and immunotherapy and the pulmonary toxicity were collected. According to whether radiotherapy was given before PD-1 inhibitor application, all patients were divided into the previous radiotherapy and non-radiotherapy groups. Survival analysis was performed by Kaplan- Meier method. Results:A total of 90 patients were enrolled including 39 cases in the previous radiotherapy group and 51 cases in the non-radiotherapy group. The median follow-up time was 22.9 months. The median progression-free survival (mPFS) in the previous radiotherapy group was 7.5 months (95% CI 5.4-9.5 months), significantly longer compared with 4.1 months (95% CI 3.1-5.1 months) in the non-radiotherapy group ( P=0.003). The median overall survival (mOS) significantly differed between two groups[15.2 months (95% CI 12.3-18.1 months) vs. 9.3 months (95% CI 6.1-12.5 months)]( P=0.040). The incidence of pulmonary toxicity showed no significant difference between two groups ( P=0.154). Conclusions:Patients with stage Ⅳ NSCLC patients in the previous radiotherapy group obtain significantly better mPFS and mOS and similar pulmonary toxicity compared with their counterparts in the non-radiotherapy group. Nevertheless, the findings remain to be validated by subsequent investigations with larger sample size.
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Objective:To evaluate the efficacy and safety of stereotactic ablative radiotherapy (SABR) in patients with pulmonary oligometastases.Methods:Clinical data of patients with pulmonary metastases treated with SABR from 2011 to 2018 were retrospectively analyzed. The local control rate (LCR) and overall survival (OS) were calculated by Kaplan- Meier method. log-rank test was used for univariate analysis and Cox’s regression model for multivariate analysis. Results:A total of 214 lung metastases were detected in 159 patients, and the median follow-up time was 43 months. The 1-, 3-and 5-year LCR were 90.1%, 73.9% and 65.8%, respectively. The 1-, 3-and 5-year OS were 73.8%, 43.6% and 11.9%, respectively. Univariate analysis showed that biological effective dose (BED)≥100 Gy was significantly correlated with LCR ( P=0.033). Cox’s multivariate analysis showed that BED and primary tumor source were the independent prognostic factors of LCR ( P=0.023, P=0.043). No>grade 3 adverse events were observed in all patients during treatment. Conclusions:SABR is a safe and effective treatment of lung oligometastases. SABR should be actively aD ministered for pulmonary oligometastases, especially for those with lesions from lung cancer and the radiation dose should be selected as BED ≥100 Gy.
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Objective:In this paper, based on the 4D dose distribution of the treatment plan, the effects of respiratory movement on the dose distribution of three-dimensional conformal radiation therapy (3DCRT) and sliding window intensity-modulated radiation therapy (SW-IMRT) techniques were analyzed, and the dose errors caused by respiratory movement based on the 4D dose distribution were evaluated.Methods:In this study, the dynamic thoracic phantom (CIRS-008A) was used to simulate the patient with a 3 cm spherical insert as the tumor. Four motion patterns were simulated with cos 4( x) and sin ( x) wave forms of 10 mm and 5 mm amplitudes. The 4DCT scans with the phantom were performed in different breathing modes, and the maximum intensity projection (MIP), average intensity projection (AIP) and 10 separate 4DCT phase images were transferred to the Eclipse treatment planning system. The targets were contoured on MIP, with corresponding 3DCRT and SW-IMRT plans designed and dose calculated on AIP. By copying the plan designed on the AIP to each phase image of the 4DCT set, the MATLAB software package was employed to register and superimpose all the phase-specific doses onto one of the reference phase to create a 4D-accumulated dose distribution. Both films (EBT2) and optically stimulated luminescence (OSLD) detectors were inserted in and around the target area of the phantom to measure the delivered doses. The calculated 4D-accumulated doses were compared to the measured doses and their differences were evaluated using Gamma analysis. Results:Under different respiration modes, the average Gamma index (3%/3 mm) passing rates between the 4D-accumulated doses and EBT2-measured doses for 3DCRT and SW-IMRT plans were (98.8±0.78)% and (96.4±1.89)%, respectively. The absolute measurements of OSLDs both inside and outside of the target area well matched the 4D-accumulated doses.Conclusions:4DCT can be effectively applied to evaluate the treatment plan dose distribution through 4D dose accumulation, which can potentially avoid cold spots and target under-coverage. Under different respiration modes, both 3DCRT and SW-IMRT plans provide dose measurements consistent with those predicted by the 4D-accumulated dose of treatment plan.
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Objective:To analyze the invasion characteristics and prognostic factors of patients with Masaoka-Koga stage Ⅲ thymoma.Methods:The tumor invasion characteristics of 179 patients who were diagnosed with Masaoka-Koga stage Ⅲ thymoma and treated in Affiliated Cancer Hospital of Zhengzhou University from January 2000 to June 2018 were analyzed retrospectively. According to the treatment methods, all patients were divided into the radical operation group ( n=94), palliative operation group ( n=39) and simple biopsy group ( n=46). The χ2 test was used to compare the classified variables, Kaplan- Meier method was utilized to calculate the cumulative survival rate, log-rank method was used for group comparison and univariate analysis, and Cox’s regression model was used for multivariate analysis. Results:Mediastinal pleural invasion (86.0%) was the most common site, followed by pericardium (50.8%), great vessel (40.8%) and lung (36.3%). The proportion of macrovascular invasion in the radical operation group was 14.9%, significantly lower than 79.5% and 60.9% in the palliative surgery group and biopsy group (both P<0.001). Multivariate analysis showed that the nature of operation ( P<0.001), age ( P=0.011), radiotherapy ( P=0.020) were the independent factors affecting overall survival (OS), while nature of operation ( P<0.001), age ( P=0.004), radiotherapy ( P=0.020), number of invasive organs ( P=0.023) and pathological type ( P=0.016) were the independent factors affecting progress-free survival (PFS). Conclusions:For patients with Masaoka-Koga stage Ⅲ thymoma, mediastinal pleura is the most common site of invasion, pericardium, lung and great vessels are also commonly invaded. The invasion of mediastinal pleura, pericardium and lung exerts slight effect on surgical resectability, whereas great vessel involvement can significantly affect surgical resectability. OS and PFS in patients undergoing radical resection are significantly better than those in patients treated with palliative resection and biopsy. Radical resection is the most important factor affecting prognosis.
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With the global pandemic of COVID-19, cytokine storms in critical patients with pneumonia is really a problem and need to be solved immediately.Low dose radiation therapy (LDRT) has been temporarily used to treat pneumonia.In the past decades, researchers were dedicated to clarify the biological mechanism of LDRT.LDRT plays a unique role in the suppression of inflammation, preliminary outcomes have been acquired in critical patients with COVID-19 pneumonia, and radiotherapy community is paying attention to this treatment strategy.This review summarizes the application of LDRT in pneumonia, its biological mechanism, the result of LDRT in COVID-19 pneumonia, the existing problems and prospective in clinic.
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Objective@#To compare relevant dosimetric parameters of non-coplanar volumetric modulated arc therapy (VMAT) in treating brain tumors in conventional flattening filter (FF) or flattening filter-free (FFF) delivery mode, aiming to explore the appropriate evaluation method of accelerator for stereotactic radiosurgery (SRS).@*Methods@#Clinical data of 10 patients with single cranial tumor were retrospectively analyzed. All patients received non-coplanar VMAT at a prescription dose of 25 Gy in 1 fraction. Dosimetric parameters including conformity index (CI), heterogeneity index (HI), gradient index (GI50, GI25), gradient, volume of the brain tissue receiving larger than 10 Gy and 12 Gy(V10 and V12) and beam-on time were statistically compared between two treatment plans by paired sample t-test.@*Results@#When FFF-VMAT was compared with FF-VMAT in SRS for intracranial tumors, Paddick gradient index GI50 was 2.91±0.34 vs.3.07±0.35, 6.91±0.28 vs.7.35±0.27 for GI25, (0.57±0.07) cm vs.(0.61±0.08) cm for gradient, respectively (all P<0.05), whereas CI did not significantly differ (P>0.05). For the normal brain tissues, the average dose was (160.64±43.64) cGy vs.(174.27±53.98) cGy, (45.35±30.32)% vs.(48.37±30.88)% for V10 and (36.69±25.15)% vs.(39.48±25.37)% for V12, respectively (all P<0.05).@*Conclusions@#Non-coplanar VMAT in FFF delivery mode can improve dose distribution and normal brain tissue sparing in the treatment of intracranial single tumors. Meanwhile, supplement of GI index and gradient index can implement comprehensive evaluation of the SRS planning.
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Objective@#To evaluate the clinical efficacy and prognostic factors of recurrent esophageal squamous cell carcinoma after neoadjuvant therapy combined with surgery.@*Methods@#From December 2011 to December 2015, 152 cases of recurrent thoracic esophageal squamous cell carcinoma after neoadjuvant therapy combined with surgery were retrospectively analyzed. The overall survival (OS) after treatment failure, clinical efficacy and prognostic factors of different salvage treatments were analyzed. OS was calculated by Kaplan-Meier method. Prognostic analysis was performed by using multivariate Cox regression model.@*Results@#The median interval of the first recurrence was 10.6(2.0 to 69.1) months. The median OS after recurrence was 8.0(0.8 to 43.3) months. The 1-, 2-and 3-year OS rates after recurrence were 36.0%, 15.1% and 5.2%, respectively. The median OS of patients with locoregional recurrence alone, distant metastasis alone and locoregional recurrence combined with distant metastasis was 11.3(1.8 to 43.3) months, 6.7(1.2 to 28.6) months and 5.1(0.8 to 22.9) months, respectively. Multivariate analysis demonstrated that neoadjuvant chemotherapy (P=0.009), ypTNM stage (P=0.012), comprehensive treatment after recurrence (P=0.000) and locoregional recurrence (P=0.026) were independently correlated with the OS of patients with recurrent esophageal squamous cell carcinoma.@*Conclusions@#Neoadjuvant therapy, ypTNM stage, recurrence pattern and post-recurrence treatment are the independent risk factors for clinical prognosis of patients with recurrent esophageal squamous cell carcinoma after neoadjuvant therapy combined with surgery. Clinical prognosis of patients with recurrent esophageal squamous cell carcinoma after neoadjuvant therapy is not satisfactory. After recurrence, combined treatment mode should be adopted according to the site of recurrence and neoadjuvant treatment mode to maximize the benefits of salvage treatment.
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Objective:To evaluate the long-term survival and identify prognostic factors of patients diagnosed with early-stage non-small cell lung cancer (ES-NSCLC) receiving stereotactic ablation radiotherapy (SABR).Methods:Clinical data of 109 ES-NSCLC patients treated with SABR in Henan Cancer Hospital from 2011 to 2018 were retrospectively analyzed. The overall survival (OS), cancer-specific survival (CSS) and progression-free survival (PFS) were calculated by Kaplan- Meier method and log-rank test. Multivariate prognostic analysis was performed by Cox regression model. Results:The median follow-up time was 44 months (2-93 months). The median OS, CSS and PFS were 78 months, 78 months and 44 months, respectively. The 1-year OS, CSS and PFS were 95.4%, 97.2% and 84.1%, and 75.6%, 79.1% and 56.6% for the 3-year OS, CSS and PFS, and 55.6%, 60.7% and 37.3% for the 5-year OS, CSS and PFS, respectively. Univariate analysis showed that ECOG score, age, smoking history and derived-neutrophil/lymphocyte ratio (dNLR) were the influencing factors of OS ( P=0.03, 0.02, 0.04, 0.001). Age, smoking history and dNLR were the influencing factors of CSS ( P=0.02, 0.03, 0.001). Multivariate analysis demonstrated that dNLR was an independent prognostic factor for OS and CSS ( P=0.001, 0.001). Conclusions:ES-NSCLC patients treated with SABR can achieve favorable survival. The dNLR is an independent prognostic factor of OS and CSS, which can be considered in clinical application.
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Objective:To propose an automatic planning platform of the Raystation planning system suitable for multi-disease and multi-plan technique by using the Raystation built-in script function.Methods:IronPython and WPF user interface framework were utilized for programming and resolving the differences in the design of different types of plans for different diseases. The program was designed from prescription identification, visual plan parameter input and cost-function setting. The efficiency of automatic planning and manual planning was compared when applied in whole brain irradiation, nasopharyngeal carcinoma, cervical cancer, esophageal cancer and breast cancer, including IMRT and VMAT. The dosimetric parameters of the whole brain irradiation were chosen.Results:Physicists were only required to enter and select the necessary parameters to achieve the plan design by using the program. Compared with the five types of diseases, the maximum efficiency of automatic planning was 1.4 times higher than that of manual planning. In the dosimetric evaluation of the whole brain irradiation plan, both manual and automatic planning could meet the clinical needs, and the D 2%, CI and HI of the target area did not significantly differ (all P>0.05). The mean D 98% of the target area and the D max of lens in the manual plan were significantly higher than those in the automatic plan by 0.4% and 7.1%(both P<0.05). Conclusion:The developed program has the function of automatic planning system, which can realize the automatic planning of multi-disease and multi-type radiotherapy, significantly improve the efficiency of plan design and has important clinical application value.