Showing papers on "Radiation-induced lung injury published in 2009"
TL;DR: Higher N TCP values are associated with a higher risk, but when comparing the expected to the observed toxicity rate, NTCP seems to underestimate the risk.
Abstract: Materials and methods. The aim was to retrospectively investigate correlations between potential predictive parameters and the occurrence of radiation-induced lung injury in patients with primary or secondary lung tumours treated with stereotactic body radiation therapy (SBRT). Sixty patients (63 tumours) underwent SBRT, with a dose of 45 Gy in 3 fractions over 5 days or 26 Gy in single fraction. The following parameters were tested for correlation with Radiation Therapy Oncology Group (RTOG) lung toxicity score: planning target volume (PTV), tumour location, primary vs. metastatic tumour, and Mean Lung Dose (in 2 Gy fractions, MLD2). Normal Tissue Complication Probability (NTCP) values were then estimated. Results. The median follow-up time was 30.9 months (range 6.7–56.7). RTOG grade 0–1 toxicity was observed in 54/63 (85.7%) and grade 2–3 in 9/63 (14.3%) cases. Mean values of MLD2 for RTOG grade 0–1 and 2–3 were respectively 11.2 Gy (95% Confidence Interval (CI) 10.1–12.3 Gy) and 20.3 Gy (95% CI 16.6–2...
71 citations
TL;DR: Hyperpolarized 3He MRI was well tolerated in all subjects with moderate to severe RILI, suggesting that functional compensatory changes may have occurred in the contralateral lung due to ipsilateral lung radiation-induced injury.
Abstract: Purpose: Therapeutic radiationdoses for thoracic tumors are significantly restricted to decrease the risk of nontumor tissue damage, yet radiation-induced lung injury (RILI) still occurs in over 1 ∕ 3 of thoracic radiation treatment cases. Although RILI can be clinically monitored using pulmonary function measurements, the regional functional effects of the injury are not well understood. Hyperpolarized He 3 magnetic resonance imaging provides measurements of regional lung function and structure with high spatial and temporal resolution; the authors use this tool longitudinally for the first time in seven subjects after clinical diagnosis of RILI in order to better understand regional changes in lung function and structure post-RILI. Methods: All subjects underwent spirometry, plethysmography, and MRI at 3.0 T 35.1 ± 12.2 weeks after radiation therapy commenced. Thoracic H 1 , static He 3 ventilation, and He 3 diffusion-weighted images were acquired to generate the He 3 apparent diffusion coefficient (ADC) and He 3 percent ventilated volume (PVV). Four subjects returned 22.0 ± 0.8 weeks after baseline imaging for follow-up spirometry and He 3 MRI measurements of ADC and PVV. Results: At baseline, PVV was significantly different ( p = 0.025 ) and lower in the ipsilateral diseased lung ( 55 ± 29 % ) compared to the contralateral nondiseased lung ( 88 ± 5 % ) . Longitudinally, significant increases were observed for He 3 MRI PVV ( 16 % ± 6 % , p = 0.012 ) and He 3 MRI ADC ( 0.02 ± 0.01 cm 2 ∕ s , p = 0.003 ) in the contralateral lung only, in the four subjects who returned for follow-up, while no changes in the ipsilateral lung were reported. Conclusions: Hyperpolarized He 3 MRI was well tolerated in all subjects with moderate to severe RILI. Functional improvements and microstructural changes were observed in the contralateral lung, while the ipsilateral lung remained stable, suggesting that functional compensatory changes may have occurred in the contralateral lung due to ipsilateral lung radiation-induced injury.
53 citations
TL;DR: It is demonstrated that highly conformal radiation can be reproducibly delivered to a small volume of rodent lung on a widely available clinical unit and the radiation-induced lung injury can be detected as early as 2 months after radiation with perfusion MRI.
Abstract: Purpose To evaluate a helical tomotherapy–based rodent radiosurgery platform that reproduces human image-guided radiosurgery treatment to study radiobiologic effects of stereotactic radiosurgery on lung tissues using functional magnetic resonance imaging (MRI). Methods and Materials Hypofractionated radisourgery (20 Gy × 3) was delivered to the right lung of three New Zealand rabbits using Helical TomoTherapy with MVCT image guidance. Contrast-enhanced MR perfusion, hyperpolarized helium-3 MR ventilation, and CT were obtained before radiation and monthly for 4 months after radiation. All MRI was performed on a 1.5-T whole-body scanner with broad-band capabilities. Results Precise dose delivery to 1.6 cc of the lower right lung was achieved without additional immobilization. No deficits were detected at baseline with respect to perfusion and ventilation. Lung perfusion deficits in the irradiated lung regions began at 2 months after radiation and worsened with time. No ventilation deficits were observed after radiation. Decrease in lung CT density in irradiated regions was observed after radiation, but the changes were less significant than those in perfusion MRI. Conclusions We demonstrated that highly conformal radiation can be reproducibly delivered to a small volume of rodent lung on a widely available clinical unit. The radiation-induced lung injury can be detected as early as 2 months after radiation with perfusion MRI. The primary pattern of injury agrees with previously reported endothelial damage to radiosurgical radiation doses. This experimental design provides a cost-effective methodology for producing radiosurgical injuries in rodents that reproduces current human treatments for studying radiation injury and agents that might affect it.
11 citations
01 May 2009
TL;DR: Using a murine model of thoracic irradiation, it is found that mice deficient in either the chemokine CCL3 or one of its receptors, CCR1, are significantly protected from radiation lung injury.
Abstract: Xuebin Yang: Molecular and Cellular Mediators In Radiation-Induced Lung Injury (Under the direction of Suzanne Kirby, M.D. Ph.D) Radiation-induced lung injury is a common adverse effect in patients receiving thoracic irradiation and for which, there is currently no effective therapy. Using a murine model of thoracic irradiation, we found that mice deficient in either the chemokine CCL3 or one of its receptors, CCR1, are significantly protected from radiation lung injury. This protected phenotype includes improved survival, virtually no pneumonitis or fibrosis, and preserved lung function when compared to wild-type mice. We further showed that a specific CCR1 inhibitor, BX471 provided similar protection. Therefore, CCR1 is a promising target for reducing radiation lung injury. To investigate the mechanisms by which CCL3/CCR1 signalling mediates radiation lung injury, we evaluated their influence on lung inflammation after irradiation. When compared with irradiated WT mice, irradiated CCL3and CCR1-deficient mice had less lung infiltration of CD4 + and CD8 + T cells; however, CD4-deficient mice showed only partial protection, while CD8-deficient mice had slightly worse fibrosis. We further analyzed inflammatory cytokines and different subsets of CD4 + lymphocytes, T H 1, T H 2, T H 17 and Treg cells, in our model. We found no differences in lung Foxp3 + Treg cells between WT and CCR1-deficient mice. Notably however, irradiated CCR1-deficient mice had less mRNA
2 citations
01 Apr 2009
1 citations
TL;DR: Ipsilateral lung MLD was the only independent factor associated with grade >2 radiation-induced lung injury in this study, so that it should be included as a dose constraint factor for 3D-CRT of NSCLC.
Abstract: 7552 Background: There are different clinical factors associated with radiation-induced lung injury in patients with non-small cell lung cancer (NSCLC) after three-dimensional conformal radiation therapy (3D-CRT) that have been studied, whereas their value are not same. According to their source, the factors can be sorted to four types. Methods: 119 NSCLC patients treated with 3D-CRT during 2003–2005 were retrospectively reviewed. They were divided into two arms according to whether grade >2 radiation- induced lung injury named by RTOG 3.0 were observed. The clinical parameters related to radiation-induced lung injury were divided into four sorts: general state of health and systematic sickness (gender, age, KPS, COPD, heart disease, diabetes), tumor-related factors (location, stage, volume), radiotherapy-related factors (dose, fraction per day, target margin, dosimetric parameters), other treatment factors (chemotherapy timing and agents). Univariate and multivariate analyses of the relation between clin...
1 citations