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1.
Anticancer Res ; 41(9): 4571-4575, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475085

RESUMO

BACKGROUND/AIM: The purpose of this study was to compare the dose distribution between scanning carbon-ion radiotherapy (sCIRT) and volumetric-modulated arc therapy with stereotactic body radiation therapy (VMAT-SBRT) for stage I non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Fifteen patients with early-stage NSCLC who underwent sCIRT at Kanagawa Cancer Center between 2018-2020 were enrolled. Dose-volume histogram parameters of the planned target volume and normal organs for sCIRT and VMAT-SBRT were evaluated. RESULTS: The homogeneity index of the target volume of sCIRT was significantly lower than that of VMAT-SBRT. The dose of sCIRT was significantly lower than that of VMAT-SBRT at low volumes in the lung, heart, spinal cord, and esophagus. CONCLUSION: The dose distribution of sCIRT for early-stage NSCLC was better than that of VMAT-SBRT.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Radioterapia com Íons Pesados/métodos , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Radioterapia de Intensidade Modulada/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
2.
J Pak Med Assoc ; 71(7): 1736-1739, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34410237

RESUMO

OBJECTIVE: To investigate the utility of quantitative lung perfusion scintigraphy and pulmonary function tests in the assessment of radiation-induced lung injury. METHODS: The prospective study was conducted at Zonguldak Bulent Ecevit University Hospital, Turkey, from May 2012 to October 2016, and comprised female breast cancer patients having undergone lung perfusion scintigraphy with Tc-99m macroaggregated albumin before and after radiotherapy. Pulmonary function tests and carbon monoxide diffusing capacity tests were also carried out on all the patients, and the relationship between treatment-related changes and its association with radiotherapy doses was analysed. Data was analysed using SPSS 19. RESULTS: There were 43 patients with a median age of 49 (interquartile range: 32-71 years). Carbon monoxide diffusing capacity values at baseline showed a significant decrease at 6 and 12 months post- radiotherapy (p<0.05), while none of the parameters of the pulmonary function tests showed a significant difference (p>0.05). Also, the median percentage of perfusion studies in the irradiated lung decreased significantly (p<0.001) at 12 months post-treatment. There was significant reduction in perfusion studies of irradiated lungs (p<0.05). CONCLUSIONS: Carbon monoxide diffusing capacity and quantitative lung perfusion scintigraphy were found to be useful tools for the early diagnosis and monitoring of radiation-induced lung injury.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Adulto , Idoso , Neoplasias da Mama/radioterapia , Feminino , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Pessoa de Meia-Idade , Perfusão , Imagem de Perfusão , Estudos Prospectivos , Testes de Função Respiratória
3.
Ann Clin Lab Sci ; 51(4): 521-528, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34452890

RESUMO

OBJECTIVE: Radioresistance-induced locoregional recurrence remains a major cause of low survival rates. However, the mechanism of treatment failure in these lung cancer patients has not been determined. In the current study, we tried to explore the potential molecular mechanism. METHODS: The fractionated irradiations were continued until the total concentration reached 80 Gy, and we established radioresistant subclones derived from A549 lines (designated as A549/R). The MTT assay, wound healing assay, transwell assay, and soft agar colony formation assay were employed to detect the proliferation, migration, invasion, and clonogenicity of the cells, respectively. Western blot and Fluorescence Activating Cell Sorter (FACS) indicated the expression of the markers. RESULTS: A549/R cells proliferated more slowly than the parental A549 cells. A significant acceleration in cell migration and invasion was revealed in A549/R cells compared with A549 cells. The expression levels of mesenchymal markers (N-cadherin, vimentin, claudin-1, and Snail) increased, while epithelial markers (E-cadherin and ß-catenin) decreased in A549/R cells. Meanwhile, the expression levels of stemness markers (Oct4, Notch1, and CD133) increased in A549/R cells, and A549/R cells showed more sphere-forming activity compared with A549 cells. CONCLUSION: Fractionated irradiation could promote epithelial-mesenchymal transition and enhance the migration, invasion, and stemness-like properties in A549 cells, elucidating the possible radioresistance mechanisms of the cancer cells.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Raios gama , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/patologia , Células A549 , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Movimento Celular , Proliferação de Células , Fracionamento da Dose de Radiação , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Invasividade Neoplásica , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/efeitos da radiação
4.
Radiologe ; 61(9): 853-862, 2021 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-34409518

RESUMO

Radiotherapy of small targets with very high single doses administered in 1 to approximately 12 fractions-carried out under image guidance and with the intention of "tumour ablation"-is called stereotactic body radiation therapy (SBRT) for extracranial tumours or metastases. Radiobiologically, besides damaging the DNA of the tumour cells, the tumour vessels are also occluded and immunological effects are triggered. The safe performance of SBRT requires a very high physical-technical effort in order to ensure sufficient protection of healthy organs. Clinically, SBRT offers a wide range of applications in curative therapy (e.g. non-small-cell lung cancer stage I). Furthermore, it is a conservative, effective and well-tolerated option for the treatment of individual metastases and an optimal combination partner in the therapy of oligometastatic tumours.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia
5.
Medicine (Baltimore) ; 100(29): e26674, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34398034

RESUMO

ABSTRACT: This study aimed to explore the dynamics of circulating tumor cells (CTCs) and CD8+ T cells in stage II-III non-small cell lung cancer patients with CTCs in different programmed death-ligand 1 (PD-L1) status treated with radiotherapy and evaluate the correlation between CTCs and CD8+ T cells.This study was a retrospective study which reviewed 69 stage II-III non-small cell lung cancer patients underwent postoperative radiotherapy and peripheral blood tests of CTCs and T lymphocyte were available before radiation, 1 week after radiation and 1 month after radiation.In this study, 25 patients had PD-L1 positive CTCs and 44 patients had PD-L1 negative CTCs. The CTCs count was significantly decreased compared with baseline in patients with different PD-L1 status CTCs at 1 week and 1 month after radiotherapy. The proportion of CD8+ T cells was significantly increased at 1 month after radiotherapy compared with baseline in the total population (mean change, 7.24 ±â€Š2.12; P < .05) and patients with PD-L1 negative CTCs (mean change, 7.17 ±â€Š2.65; P < .05). One month after radiotherapy, the proportion of CD8+ T cells was negatively correlated with the CTCs count in the total population (r = -0.255, P = .034) and PD-L1 negative patients (r = -0.330, P = .029). In patients with PD-L1 negative CTCs, the CTCs count 1 week after radiotherapy (hazard ratio, 0.150 [95% confidence intervals., 0.027-0.840], P = .031) and the proportion of CD8+ T cells 1 month after radiotherapy (hazard ratio, 7.961 [95% confidence intervals, 1.028-61.68], P = .047) were independent prognostic factors for disease recurrence.After radiotherapy, only PD-L1-negative patients had a significant increase in the CD8+ T cell levels, while it was negatively correlated with CTCs count and was an independent prognostic factors of disease recurrence.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Células Neoplásicas Circulantes/metabolismo , Receptor de Morte Celular Programada 1/genética , Adolescente , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , China , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
6.
J Appl Clin Med Phys ; 22(9): 215-226, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34406710

RESUMO

BACKGROUND AND PURPOSE: When treating lung tumors with stereotactic body radiation therapy (SBRT), patient immobilization is of outmost importance. In this study, the intra-fractional shifts of the patient (based on bony anatomy) and the tumor (based on the visible target volume) are quantified, and the associated impact on the delivered dose is estimated for a frameless immobilization approach in combination with surface guided radiation therapy (SGRT) monitoring. METHODS: Cone beam computed tomographies (CBCT) were collected in free breathing prior and after each treatment for 25 patients with lung tumors, in total 137 fractions. The CBCT collected after each treatment was registered to the CBCT collected before each treatment with focus on bony anatomy to determine the shift of the patient, and with focus on the visible target volume to determine the shift of the tumor. Rigid registrations with 6 degrees of freedom were used. The patients were positioned in frameless immobilizations with their position and respiration continuously monitored by a commercial SGRT system. The patients were breathing freely within a preset gating window during treatment delivery. The beam was automatically interrupted if isocenter shifts >4 mm or breathing amplitudes outside the gating window were detected by the SGRT system. The time between the acquisition of the CBCTs was registered for each fraction to examine correlations between treatment time and patient shift. The impact of the observed shifts on the dose to organs at risk (OAR) and the gross tumor volume (GTV) was assessed. RESULTS: The shift of the patient in the CBCTs was ≤2 mm for 132/137 fractions in the vertical (vrt) and lateral (lat) directions, and 134/137 fractions in the longitudinal (lng) direction and ≤4 mm in 134/137 (vrt) and 137/137 (lat, lng) of the fractions. The shift of the tumor was ≤2 mm in 116/137 (vrt), 123/137 (lat) and 115/137 (lng) fractions and ≤4 mm in 136/137 (vrt), 137/137 (lat), and 135/137 (lng) fractions. The maximal observed shift in the evaluated CBCT data was 4.6 mm for the patient and 7.2 mm for the tumor. Rotations were ≤3.3ᵒ for all fractions and the mean/standard deviation were 0.2/1.0ᵒ (roll), 0.1/0.8ᵒ (yaw), and 0.3/1.0ᵒ (pitch). The SGRT system interrupted the beam due to intra-fractional isocenter shifts >4 mm for 21% of the fractions, but the patients always returned within tolerance without the need of repositioning. The maximal observed isocenter shift by the SGRT system during the beam holds was 8 mm. For the respiration monitoring, the beam was interrupted at least one time for 54% of the fractions. The visual tumor was within the planned internal target volume (ITV) for 136/137 fractions in the evaluated CBCT data collected at the end of each fraction. For the fraction where the tumor was outside the ITV, the D98% for the GTV decreased with 0.4 Gy. For the OARs, the difference between planned and estimated dose from the CBCT data (D2% or Dmean ) was ≤2.6% of the prescribed PTV dose. No correlation was found between treatment time and the magnitude of the patient shift. CONCLUSIONS: Using SGRT for motion management and respiration monitoring in combination with a frameless immobilization is a feasible approach for lung SBRT.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Radioterapia Guiada por Imagem , Tomografia Computadorizada de Feixe Cônico , Humanos , Pulmão , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Movimento , Planejamento da Radioterapia Assistida por Computador
7.
Comput Methods Programs Biomed ; 209: 106338, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34390935

RESUMO

PURPOSE: To evaluate the quality of robust stereotactic body proton therapy (RSBPT) plans generated by one-clicking scripting method for patients with lung cancer. MATERIALS AND METHODS: Retrospective analysis was performed on fifty lung cancer patients whose plan with robustly stereotactic body radiation therapy (SBRT). Thirty out of fifty patients were used for training to build a regression model, based on robust SBRT reference doses, to predict EUD values of ROIs for robust SBPT planning. Thereafter, robust SBPT plans with both automated EUD-Based mimicking (Automated Robust Proton ARP) and manual (Manual Robust Proton MRP) methods were evaluated in the remaining 20 patients. Plans were compared in terms of dosimetric parameters and planning time. RESULTS: A statistically significantly improvement in target dose fall off was observed for ARP plans compare to MRP plans (Dose fall off: 135 for MRP and 88 for ARP, p < 0.01), while no differences in target coverage and conformity. A statistically significantly reduce in normal lung tissue were observed for ARP plans compare to MRP plans (Lung [Dmean cGy (RBE)]: MRP: 478 vs. ARP: 351, p < 0.01; Lung [V5Gy (RBE) (%)]: MRP: 16.1 vs. ARP: 12.1, p < 0.01; Lung [V20Gy (RBE) (%)]: MRP: 8.5 vs. ARP: 6.8, p < 0.01). Planning time was reduced for ARP plans compare to MRP plans (optimization time: 12 min for MRP vs. 8 min for ARP; total plan time: 23 min for MRP vs. 18 min for ARP). CONCLUSION: The automated robust SBPT plans using EUD-Based mimicking of SBRT reference dose improve target dose fall off, reduced the radiation doses to the lungs, reduce planning time, which might be beneficial for patient with lung cancer in clinical.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Neoplasias Pulmonares/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
9.
J Appl Clin Med Phys ; 22(9): 103-112, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34258853

RESUMO

Patient breathing during lung cancer radiotherapy reduces the ability to keep a sharp dose gradient between tumor and normal tissues. To mitigate detrimental effects, accurate information about the tumor position is required. In this work, we evaluate the errors in modeled tumor positions over several fractions of a simple tumor motion model driven by a surface surrogate measure and its time derivative. The model is tested with respect to four different surface surrogates and a varying number of surrogate and image acquisitions used for model training. Fourteen patients were imaged 100 times with cine CT, at three sessions mimicking a planning session followed by two treatment fractions. Patient body contours were concurrently detected by a body surface laser scanning system BSLS from which four surface surrogates were extracted; thoracic point TP, abdominal point AP, the radial distance mean RDM, and a surface derived volume SDV. The motion model was trained on session 1 and evaluated on sessions 2 and 3 by comparing modeled tumor positions with measured positions from the cine images. The number of concurrent surrogate and image acquisitions used in the training set was varied, and its impact on the final result was evaluated. The use of AP as a surface surrogate yielded the smallest error in modeled tumor positions. The mean deviation between modeled and measured tumor positions was 1.9 mm. The corresponding deviations for using the other surrogates were 2.0 mm (RDM), 2.8 mm (SDV), and 3.0 mm (TP). To produce a motion model that accurately models the tumor position over several fractions requires at least 10 simultaneous surrogate and image acquisitions over 1-2 minutes.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Tomografia Computadorizada Quadridimensional , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Movimento , Planejamento da Radioterapia Assistida por Computador , Respiração
10.
J Appl Clin Med Phys ; 22(8): 156-167, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34310827

RESUMO

PURPOSE: Re-planning for four-dimensional computed tomography (4DCT)-based lung adaptive radiotherapy commonly requires deformable dose mapping between the planning average-intensity image (AVG) and the newly acquired AVG. However, such AVG-AVG deformable image registration (DIR) lacks accuracy assessment. The current work quantified and compared geometric accuracies of AVG-AVG DIR and corresponding phase-phase DIRs, and subsequently investigated the clinical impact of such AVG-AVG DIR on deformable dose mapping. METHODS AND MATERIALS: Hybrid intensity-based AVG-AVG and phase-phase DIRs were performed between the planning and mid-treatment 4DCTs of 28 non-small cell lung cancer patients. An automated landmark identification algorithm detected vessel bifurcation pairs in both lungs. Target registration error (TRE) of these landmark pairs was calculated for both DIR types. The correlation between TRE and respiratory-induced landmark motion in the planning 4DCT was analyzed. Global and local dose metrics were used to assess the clinical implications of AVG-AVG deformable dose mapping with both DIR types. RESULTS: TRE of AVG-AVG and phase-phase DIRs averaged 3.2 ± 1.0 and 2.6 ± 0.8 mm respectively (p < 0.001). Using AVG-AVG DIR, TREs for landmarks with <10 mm motion averaged 2.9 ± 2.0 mm, compared to 3.1 ± 1.9 mm for the remaining landmarks (p < 0.01). Comparatively, no significant difference was demonstrated for phase-phase DIRs. Dosimetrically, no significant difference in global dose metrics was observed between doses mapped with AVG-AVG DIR and the phase-phase DIR, but a positive linear relationship existed (p = 0.04) between the TRE of AVG-AVG DIR and local dose difference. CONCLUSIONS: When the region of interest experiences <10 mm respiratory-induced motion, AVG-AVG DIR may provide sufficient geometric accuracy; conversely, extra attention is warranted, and phase-phase DIR is recommended. Dosimetrically, the differences in geometric accuracy between AVG-AVG and phase-phase DIRs did not impact global lung-based metrics. However, as more localized dose metrics are needed for toxicity assessment, phase-phase DIR may be required as its lower mean TRE improved voxel-based dosimetry.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Algoritmos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Tomografia Computadorizada Quadridimensional , Humanos , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Planejamento da Radioterapia Assistida por Computador
11.
Br J Radiol ; 94(1125): 20210176, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34233469

RESUMO

OBJECTIVES: While hypofractionated stereotactic body radiotherapy (SBRT) has been largely adopted in the adult setting, its use remains limited in pediatric patients. This is due, among other factors, to fear of potential toxicities of hypofractionated regimens at a young age. In this context, we report the preliminary acute (<3 months from SBRT) and middle-term (3-24 months) toxicity results of a national prospective study investigating SBRT in pediatric patients. METHODS: Between 2013 and 2019, 61 patients were included. The first 40 patients (median age: 12 y, range: 3-20) who completed a 2-year-follow-up were included in the present analysis. SBRT was used for treating lung, brain or (para)spinal lesions, either as first irradiation (35%) or in the reirradiation setting (65%). RESULTS: Acute and middle-term grade ≥2 toxicities occurred in 12.5 and 7.5% of the patients, respectively. No grade ≥4 toxicities occurred. Almost all toxicities occurred in the reirradiation setting. CONCLUSION: SBRT showed a favorable safety profile in young patients treated for lung, brain, and (para)spinal lesions. ADVANCES IN KNOWLEDGE: SBRT appeared to be safe in pediatric patients treated for multiple oncology indications. These results support further evaluation of SBRT, which may have a role to play in this patient population in the future.


Assuntos
Neoplasias Encefálicas/radioterapia , Fracionamento da Dose de Radiação , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Neoplasias da Coluna Vertebral/radioterapia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , França , Humanos , Masculino , Pediatria/métodos , Estudos Prospectivos , Radiocirurgia/efeitos adversos , Reirradiação/métodos , Resultado do Tratamento , Adulto Jovem
12.
World J Surg Oncol ; 19(1): 214, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34271911

RESUMO

BACKGROUND: The radiation-induced lung injury (RILI) in patients with advanced non-small cell lung cancer (NSCLS) is very common in clinical settings; we aimed to evaluate the risk factors of RILI in NSCLS patients, to provide insights into the treatment of NSCLS. METHODS: NSCLC patients undergoing three-dimensional conformal radiotherapy (3D-CRT) in our hospital from June 1, 2018, to June 30, 2020, were included. The characteristics and treatments of RILI and non-RILI patients were analyzed. Logistic regression analyses were conducted to assess the risk factors of RILI in patients with NSCLC. RESULTS: A total of 126 NSCLC patients were included; the incidence of RILI in NSCLC patients was 35.71%. There were significant differences in diabetes, smoke, chronic obstructive pulmonary disease (COPD), concurrent chemotherapy, radiotherapy dose, and planning target volume (PTV) between the RILI group and the non-RILI group (all P < 0.05). Logistic regression analyses indicated that diabetes (OR 3.076, 95%CI 1.442~5.304), smoke (OR 2.745, 95%CI 1.288~4.613), COPD (OR 3.949, 95%CI 1.067~5.733), concurrent chemotherapy (OR 2.072, 95%CI 1.121~3.498), radiotherapy dose ≥ 60 Gy (OR 3.841, 95%CI 1.932~5.362), and PTV ≥ 396 (OR 1.247, 95%CI 1.107~1.746) were the independent risk factors of RILI in patients with NSCLC (all P < 0.05). CONCLUSIONS: RILI is commonly seen in NSCLS patients; early targeted measures are warranted for patients with those risk factors; future studies with larger sample sizes and different areas are needed to further elucidate the influencing factors of RILI in the treatment of NSCLS.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Lesão Pulmonar , Neoplasias Pulmonares , Radioterapia Conformacional , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Humanos , Neoplasias Pulmonares/radioterapia , Prognóstico , Dosagem Radioterapêutica , Radioterapia Conformacional/efeitos adversos , Fatores de Risco
13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(6): 615-619, 2021 Jun 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34275930

RESUMO

OBJECTIVES: To compare 2 dynamic conformal arc plans based on the high dose rate flattening filter free (FFF) beams, and to evaluate the dosimetric differences. METHODS: A total of 20 patients with early peripheral non-small cell lung cancer were selected, and 2 dynamic conformal arc plans were designed in the Eclipse 10.0 treatment planning system (TPS). One of them was based on tumor-center (T-DCA), and the other was based on iso-center (Iso-DCA). Both plans were created by using the Truebeam linear accelerator, based on 6 MV FFF photons with a dose rate at 1 400 monitor unit (MU)/min. All patients received the prescribed dose of 4 800 cGy in 4 fractions (1 200 cGy/fraction). Target coverage and organ at risk limits were planned and designed according to the Radiation Therapy Oncology Group (RTOG) Criteria, and were compared between the T-DCA and the Iso-DCA plans. RESULTS: There was no significant difference in the target coverage between the T-DCA and Iso-DCA plans (P>0.05). Conformal index and homogeneity index had no significant differences (both P>0.05), but the percentage of the maximum dose in any direction 2 cm away from the planned target area (D2 cm) and the ratio of the volume wrapped by the isodose line of 50% prescription dose to the volume of the planned target area (R50%) showed significant differences (both P<0.05). The MU of the Iso-DCA plan was increased by 21% compared with that of the T-DCA plan. Except the maximum dose of spinal cord and esophagus, there was no significant difference in the other dosimetric parameters of the organs at risk between the T-DCA and the Iso-DCA plans (all P>0.05). CONCLUSIONS: The dose fall-off of Iso-DCA plan is better than T-DCA plan, but the T-DCA plan is consistently superior in sparing dose to spinal cord and esophagus, and the T-DCA plan has fewer MU.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Radioterapia de Intensidade Modulada , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
14.
Med Phys ; 48(8): 4425-4437, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34214201

RESUMO

PURPOSE: Intensity-modulated proton therapy (IMPT) for lung tumors with a large tumor movement is challenging due to loss of robustness in the target coverage. Often an upper cut-off at 5-mm tumor movement is used for proton patient selection. In this study, we propose (1) a robust and easily implementable treatment planning strategy for lung tumors with a movement larger than 5 mm, and (2) a four-dimensional computed tomography (4DCT) robust evaluation strategy for evaluating the dose distribution on the breathing phases. MATERIALS AND METHODS: We created a treatment planning strategy based on the internal target volume (ITV) concept (aim 1). The ITV was created as a union of the clinical target volumes (CTVs) on the eight 4DCT phases. The ITV expanded by 2 mm was the target during robust optimization on the average CT (avgCT). The clinical plan acceptability was judged based on a robust evaluation, computing the voxel-wise min and max (VWmin/max) doses over 28 error scenarios (range and setup errors) on the avgCT. The plans were created in RayStation (RaySearch Laboratories, Stockholm, Sweden) using a Monte Carlo dose engine, commissioned for our Mevion S250i Hyperscan system (Mevion Medical Systems, Littleton, MA, USA). We developed a new 4D robust evaluation approach (4DRobAvg; aim 2). The 28 scenario doses were computed on each individual 4DCT phase. For each scenario, the dose distributions on the individual phases were deformed to the reference phase and combined to a weighted sum, resulting in 28 weighted sum scenario dose distributions. From these 28 scenario doses, VWmin/max doses were computed. This new 4D robust evaluation was compared to two simpler 4D evaluation strategies: re-computing the nominal plan on each individual 4DCT phase (4DNom) and computing the robust VWmin/max doses on each individual phase (4DRobInd). The treatment planning and dose evaluation strategies were evaluated for 16 lung cancer patients with tumor movement of 4-26 mm. RESULTS: The ratio of the ITV and CTV volumes increased linearly with the tumor amplitude, with an average ratio of 1.4. Despite large ITV volumes, a clinically acceptable plan fulfilling all target and organ at risk (OAR) constraints was feasible for all patients. The 4DNom and 4DRobInd evaluation strategies were found to under- or overestimate the dosimetric effect of the tumor movement, respectively. 4DRobInd showed target underdosage for five patients, not observed in the robust evaluation on the avgCT or in 4DRobAvg. The accuracy of dose deformation used in 4DRobAvg was quantified and found acceptable, with differences for the dose-volume parameters below 1 Gy in most cases. CONCLUSION: The proposed ITV-based planning strategy on the avgCT was found to be a clinically feasible approach with adequate tumor coverage and no OAR overdosage even for large tumor movement. The new proposed 4D robust evaluation, 4DRobAvg, was shown to give an easily interpretable understanding of the effect of respiratory motion dose distribution, and to give an accurate estimate of the dose delivered in the different breathing phases.


Assuntos
Neoplasias Pulmonares , Terapia com Prótons , Radioterapia de Intensidade Modulada , Tomografia Computadorizada Quadridimensional , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Respiração
15.
Clinics (Sao Paulo) ; 76: e2769, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34231708

RESUMO

OBJECTIVES: To explore the effect of tumor and normal lung volumes on lung volume-dose parameters in patients with non-small-cell lung cancer (NSCLC) who had undergone intensity-modulated radiation therapy (IMRT). METHODS: The clinical data of 208 patients with NSCLC who underwent radical IMRT between June 2014 and June 2018 were retrospectively analyzed. A regression model curve was used to evaluate the effect of tumor and normal lung volumes on normal lung relative volumes receiving greater than 5 and 20 Gy (V5, V20), on mean lung dose (MLD), and on absolute volumes spared from greater than 5 and 20 Gy (AVS5, AVS20). RESULTS: The V5, V20, and MLD of the bilateral lung were fitted to a quadratic equation curve with the change in tumor volume, which increased initially and then decreased when the tumor volume increased. The V5, V20, and MLD of the lung reached their apex when the tumor volumes were 288.07, 341.69, and 326.83 cm3, respectively. AVS5 and AVS20 decreased in a logarithmic curve with an increase in tumor volume. The V5, V20, and MLD of the small normal lung volume group were all significantly higher than those of the large normal lung volume group (p<0.001, p=0.004, p=0.002). However, the AVS5 and AVS20 of the small normal lung volume group were all significantly lower than those of the large normal lung volume group (p<0.001). CONCLUSION: The effects of tumor volume and normal lung volume on dose-volume parameters should be considered. AVS5 is an important supplementary dose limitation parameter for patients whose tumor volume exceeds a certain boundary value (approximately 300 cm3).


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Medidas de Volume Pulmonar , Dosagem Radioterapêutica , Estudos Retrospectivos
17.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208396

RESUMO

Non-small cell lung cancer (NSCLC) continues to be the leading cause of cancer death worldwide. Recently, targeting molecules whose functions are associated with tumorigenesis has become a game changing adjunct to standard anti-cancer therapy. As evidenced by the results of preclinical and clinical investigations, whole-body irradiations (WBI) with X-rays at less than 0.1-0.2 Gy per fraction can induce remissions of various neoplasms without inciting adverse side effects of conventional chemo- and radiotherapy. In the present study, a murine model of human NSCLC was employed to evaluate for the first time the anti-neoplastic efficacy of WBI combined with inactivation of CTLA-4, PD-1, and/or HSP90. The results indicate that WBI alone and in conjunction with the inhibition of the function of the cytotoxic T-lymphocyte antigen-4 (CTLA-4) and the programmed death-1 (PD-1) receptor immune checkpoints (ICs) and/or heat shock protein 90 (HSP90) markedly reduced tumorigenesis in mice implanted by three different routes with the syngeneic Lewis lung cancer cells and suppressed clonogenic potential of Lewis lung carcinoma (LLC1) cells in vitro. These results were associated with the relevant changes in the profile of pro- and anti-neoplastic immune cells recruited to the growing tumors and the circulating anti- and pro-inflammatory cytokines. In contrast, inhibition of the tested molecular targets used either separately or in combination with each other did not exert notable anti-neoplastic effects. Moreover, no significant synergistic effects were detected when the inhibitors were applied concurrently with WBI. The obtained results supplemented with further mechanistic explanations provided by future investigations will help design the effective strategies of treatment of lung and other cancers based on inactivation of the immune checkpoint and/or heat shock molecules combined with low-dose radiotherapy.


Assuntos
Proteínas de Choque Térmico/metabolismo , Proteínas de Checkpoint Imunológico/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Transplante de Neoplasias , Dosagem Radioterapêutica , Irradiação Corporal Total , Animais , Células Clonais , Pulmão/patologia , Contagem de Linfócitos , Linfócitos do Interstício Tumoral , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Ensaio Tumoral de Célula-Tronco
18.
Life Sci ; 281: 119721, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34146555

RESUMO

PURPOSE: Pneumonitis and lung fibrosis, as the most common compliances of lung irradiation, can affect the quality of life. The use of radio-protective agents can ameliorate these injuries. This study aimed to review the potential protective role of melatonin in the treatment of radiation-induced Pneumonitis and lung fibrosis. METHODS: The current systematic study was conducted based on PRISMA guidelines to identify relevant literature on " the effect of melatonin on radiation-induced pneumonitis and lung fibrosis" in the electronic databases of Web of Science, Embase, PubMed, and Scopus up to January 2021. Eighty-one articles were screened in accordance with the inclusion and exclusion criteria of the study. Finally, eight articles were included in this systematic review. RESULTS: The finding showed that the lung irradiation-induced pneumonitis and lung fibrosis. The co-treatment with melatonin could alleviate these compliances through its anti-oxidant and anti-inflammatory actions. Melatonin through upregulation of some enzymes such as catalase, superoxide dismutase, glutathione, NADPH oxidases 2 and 4, dual oxidases 1 and 2, and also downregulation of malondialdehyde reduced oxidative stress following lung radiation. Moreover, melatonin through its anti-inflammatory effects, can attenuate the increased levels of nuclear factor kappa B, tumor necrosis factor alpha, transforming growth factor beta 1, SMAD2, interleukin (IL)-4, IL-4 receptor-a1 (IL4ra1), and IL-1 beta following lung radiation. The histological damages induced by ionizing radiation were also alleviated by co-treatment with melatonin. CONCLUSION: According to the obtained results, it was found that melatonin can have anti-pneumonitis and anti-fibrotic following lung irradiation.


Assuntos
Neoplasias Pulmonares/radioterapia , Pulmão/efeitos da radiação , Melatonina/farmacologia , Pneumonia/etiologia , Fibrose Pulmonar/etiologia , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Animais , Humanos , Pneumonia/prevenção & controle , Fibrose Pulmonar/prevenção & controle
19.
Phys Med ; 88: 53-64, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34175747

RESUMO

INTRODUCTION: Dose-response relationships for local control of lung tumours treated with stereotactic body radiotherapy (SBRT) have proved ambiguous, however, these have been based on the prescribed or planned dose. Delivered dose to the target may be a better predictor for local control. In this study, the probability of the delivered minimum dose to the clinical target volume (CTV) in relation to the prescribed dose was estimated for a cohort of patients, considering geometrical uncertainties. MATERIALS AND METHODS: Delivered doses were retrospectively simulated for 50 patients treated with SBRT for lung tumours, comparing two image-guidance techniques: pre-treatment verification computed tomography (IG1) and online cone-beam computed tomography (IG2). The prescribed dose was typically to the 67% isodose line of the treatment plan. Simulations used in-house software that shifted the static planned dose according to a breathing motion and sampled setup/matching errors. Each treatment was repeatedly simulated, generating a multiplicity of dose-volume histograms (DVH). From these, tumour-specific and population-averaged statistics were derived. RESULTS: For IG1, the probability that the minimum CTV dose (D98%) exceeded 100% of the prescribed dose was 90%. With IG2, this probability increased to 99%. CONCLUSIONS: Doses below the prescribed dose were delivered to a considerably larger part of the population prior to the introduction of online soft-tissue image-guidance. However, there is no clear evidence that this impacts local control, when compared to previous published data.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
20.
Medicine (Baltimore) ; 100(24): e26367, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34128893

RESUMO

BACKGROUND: Programmed cell death-1/programmed cell death 1 ligand 1 (PD-1/PD-L1) inhibitors are a group of immune checkpoint inhibitors immunotherapy for cancer treatment. These immune checkpoint inhibitors are becoming first-line treatments for several types of cancer. Radiotherapy for cancer is a traditional treatment and the therapeutic effect is not satisfactory due to the side effect of chemotherapeutic drugs. This study aims to evaluate the efficacy and safety of PD1/PD-L1 inhibitor immunotherapy combined chemotherapy for inoperable advanced lung cancer. METHODS: We will utilize PubMed, PubMed Central, EMbase, Medline, CNKI, WAN FANG Database, and Web of Science to screen eligible studies published from January 1, 2015 to December 30, 2020. Two reviewers will extract data and evaluate the risk of bias independently. The quality of the included studies will be evaluated using the RevMan 5.3 software for data analysis. RESULTS: This review will summarize high-quality evidence of trials to evaluate the precise medicine efficacy and safety of PD1/PD-L1 inhibitor combined radiotherapy for inoperable advanced lung cancer. CONCLUSIONS: The findings of the systematic review will provide scientific evidence of the efficacy and safety of PD1/PD-L1 inhibitor combined radiotherapy for inoperable advanced lung cancer to guide the clinician's drug use. ETHICS AND DISSEMINATION: Not applicable. INPLASY REGISTRATION NUMBER: INPLASY202140123.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Metanálise como Assunto , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Revisões Sistemáticas como Assunto , Antineoplásicos Imunológicos/efeitos adversos , Protocolos Clínicos , Terapia Combinada , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos
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