Humans ; Pulmonary Alveolar Proteinosis/radiotherapy* ; Small Cell Lung Carcinoma/radiotherapy* ; Lung ; Bronchoalveolar Lavage ; Lung Neoplasms/radiotherapy*

Brachytherapy ; methods ; Brain Neoplasms ; radiotherapy ; Glioma ; radiotherapy ; Humans ; Iodine Radioisotopes ; therapeutic use ; Liver Neoplasms ; radiotherapy ; Lung Neoplasms ; radiotherapy ; Male ; Mouth Neoplasms ; radiotherapy ; Neoplasms ; radiotherapy ; Pancreatic Neoplasms ; radiotherapy ; Prostatic Neoplasms ; radiotherapy ; Radiotherapy Dosage ; Survival Rate

Stereotactic body radiation therapy (SBRT) is a newly developed technique currently in clinical use. SBRT originated from stereotactic radiosurgery for intracranial tumors. SBRT has been widely used clinically for lung cancer. The practice of SBRT demands different kinds of patient fixation, breathing control, target determination, treatment planning, and verifications. The history and current standard technique are reviewed. Clinical studies of lung cancer showed high local control rates with acceptable toxicities. Past and on-going clinical trials are reviewed.
Humans ; Lung ; Lung Neoplasms ; Radiosurgery ; Radiotherapy, Conformal ; Respiration

BACKGROUND: Immunotherapy (IT) is recommended for the treatment of advanced non-small cell lung cancer (NSCLC), while brain radiotherapy (RT) is the mainstream treatment for patients with brain metastases (BM). This study aimed to investigate the efficacy and safety of combined use of RT and IT. METHODS: The date was limited to May 1, 2022, and literature searches were carried out in CNKI, Wanfang, PubMed, EMBASE and Cochrane databases. Heterogeneity was judged using the I2 test and P value. Publication bias was assessed using a funnel plot. The quality of included studies was assessed using the Newcastle-Ottawa Scale (NOS). Statistical analysis was performed using Stata 16.0 software. RESULTS: A total of 17 articles involving 2,636 patients were included. In the comparison of RT+IT group and RT group, no significant difference was found in overall survival (OS) (HR=0.85, 95%CI: 0.52-1.38, I2=73.9%, Pheterogeneity=0.001) and intracranial distance control (DBC) (HR=1.04, 95%CI: 0.55-1.05, I2=80.5%, Pheterogeneity<0.001), but the intracranial control (LC) in the RT+IT group was better than the RT group (HR=0.46, 95%CI: 0.22-0.94, I2=22.2%, Pheterogeneity=0.276), and the risk of radiation necrosis/treatment-related imaging changes (RN/TRIC) was higher than RT (HR=1.72, 95%CI: 1.12-2.65, I2=40.2%, Pheterogeneity=0.153). In the comparison between the RT+IT concurrent group and the sequential group, no significant difference was found in OS (HR=0.62, 95%CI: 0.27-1.43, I2=74.7%, Pheterogeneity=0.003) and RN/TRIC (HR=1.72, 95%CI: 0.85-3.47, I2=0%, Pheterogeneity=0.388) was different between the two groups. However, DBC in the concurrent treatment group was better than that in the sequential treatment group (HR=0.77, 95%CI: 0.62-0.96, I2=80.5%, Pheterogeneity<0.001). CONCLUSIONS RT combined with IT does not improve the OS of NSCLC patients with BM, but also increases the risk of RN/TRIC. In addition, compared with sequential RT and IT, concurrent RT and IT improved the efficacy of DBC.
Humans ; Lung Neoplasms/radiotherapy* ; Carcinoma, Non-Small-Cell Lung/radiotherapy* ; Brain Neoplasms/radiotherapy* ; Immunotherapy/methods* ; Radiation Injuries

PURPOSE: The objective of this study was to compare dosimetric characteristics of three-dimensional conformal radiotherapy (3D-CRT) and two types of intensity-modulated radiotherapy (IMRT) which are step-and-shoot intensity modulated radiotherapy (s-IMRT) and modulated arc therapy (mARC) for thoracic esophageal cancer and analyze whether IMRT could reduce organ-at-risk (OAR) dose. MATERIALS AND METHODS: We performed 3D-CRT, s-IMRT, and mARC planning for ten patients with thoracic esophageal cancer. The dose-volume histogram for each plan was extracted and the mean dose and clinically significant parameters were analyzed. RESULTS: Analysis of target coverage showed that the conformity index (CI) and conformation number (CN) in mARC were superior to the other two plans (CI, p = 0.050; CN, p = 0.042). For the comparison of OAR, lung V5 was lowest in s-IMRT, followed by 3D-CRT, and mARC (p = 0.033). s-IMRT and mARC had lower values than 3D-CRT for heart V30 (p = 0.039), V40 (p = 0.040), and V50 (p = 0.032). CONCLUSION: Effective conservation of the lung and heart in thoracic esophageal cancer could be expected when using s-IMRT. The mARC was lower in lung V10, V20, and V30 than in 3D-CRT, but could not be proven superior in lung V5. In conclusion, low-dose exposure to the lung and heart were expected to be lower in s-IMRT, reducing complications such as radiation pneumonitis or heart-related toxicities.
Esophageal Neoplasms ; Heart ; Humans ; Lung ; Radiation Pneumonitis ; Radiotherapy ; Radiotherapy, Conformal ; Radiotherapy, Intensity-Modulated

This study was performed to assist in the prediction of the clinical tolerance of patients with lung cancer to irradiation. MATERIALS AND METHODS: The changes in lung function of 26 patients with lung carcinomas, who had received radiation with curative intent, or postoperative adjuvant radiotherapy, were prospectively studied. Their pulmonary function tests were conducted at presentation, and then at 2 weeks, 2 months, and 6 months, following radiotherapy. RESULTS: When the parameters of postirradiation pulmonary functions (2 weeks, 2 months and 6 months) were compared with the preirradiation baseline data, there was a statistically significant decrease in FEF25~75% at 2 months, but the rest of the parameters showed no significant change following irradiation. However, when the baseline lung function was compared with the lung function at the lowest FVC, in patients with curative radiotherapy, there was a statistically significant decrease of about 10% in the FEV1 and DLCO. CONCLUSION: Preirradiation assessment of pulmonary functions, particularly the FEV1 and DLCO will be useful for the prediction of the clinical tolerance to irradiation.
Humans ; Lung Neoplasms* ; Lung* ; Prospective Studies ; Radiotherapy ; Radiotherapy, Adjuvant ; Respiratory Function Tests

PURPOSE: 3D conformal radiotherapy, the optimum dose delivered to the tumor and provided the risk of normal tissue unless marginal miss, was restricted by organ motion. For tumors in the thorax and abdomen, the planning target volume (PTV) is decided including the margin for movement of tumor volumes during treatment due to patients breathing. We designed the respiratory gating radiotherapy device (RGRD) for using during CT simulation, dose planning and beam delivery at identical breathing period conditions. Using RGRD, reducing the treatment margin for organ (thorax or abdomen) motion due to breathing and improve dose distribution for 3D conformal radiotherapy. MATERIALS AND METHODS: The internal organ motion data for lung cancer patients were obtained by examining the diaphragm in the supine position to find the position dependency. We made a respiratory gating radiotherapy device (RGRD) that is composed of a strip band, drug sensor, micro switch, and a connected on-off switch in a LINAC control box. During same breathing period by RGRD, spiral CT scan, virtual simulation, and 3D dose planing for lung cancer patients were performed, without an extended PTV margin for free breathing, and then the dose was delivered at the same positions. We calculated effective volumes and normal tissue complication probabilities (NTCP) using dose volume histograms for normal lung, and analyzed changes in doses associated with selected NTCP levels and tumor control probabilities (TCP) at these new dose levels. The effects of 3D conformal radiotherapy by RGRD were evaluated with DVH (Dose Volume Histogram), TCP, NTCP and dose statistics. RESULTS: The average movement of a diaphragm was 1.5 cm in the supine position when patients breathed freely. Depending on the location of the tumor, the magnitude of the PTV margin needs to be extended from 1 cm to 3 cm, which can greatly increase normal tissue irradiation, and hence, results in increase of the normal tissue complications probability. Simple and precise RGRD is very easy to setup on patients and is sensitive to length variation (+2 mm), it also delivers on-off information to patients and the LINAC machine. We evaluated the treatment plans of patients who had received conformal partial organ lung irradiation for the treatment of thorax malignancies. Using RGRD, the PTV margin by free breathing can be reduced about 2 cm for moving organs by breathing. TCP values are almost the same values (4-5% increased) for lung cancer regardless of increasing the PTV margin to 2.0 cm but NTCP values are rapidly increased (60-70% increased) for upon extending PTV margins by 2.0 cm. CONCLUSION: Internal organ motion due to breathing can be reduced effectively using our simple RGRD. This method can be used in clinical treatments to reduce organ motion induced margin, thereby reducing normal tissue irradiation. Using treatment planning software, the dose to normal tissues was analyzed by comparing dose statistics with and without RGRD. Potential benefits of radiotherapy derived from reduction or elimination of planning target volume (PTV) margins associated with patient breathing through the evaluation of the lung cancer patients treated with 3D conformal radiotherapy.
Abdomen ; Diaphragm ; Humans ; Lung ; Lung Neoplasms ; Radiotherapy ; Radiotherapy, Conformal* ; Respiration ; Supine Position ; Thorax ; Tomography, Spiral Computed

PURPOSE : To investigate the feasibility of intensity modulated radiotherapy (IMRT) as a method of boost radiotherapy following the initial irradiation by the conventional anterior / posterior opposed beams for centrally located non-small-cell lung cancer through the evaluation of dose distributions according to the various boost methods. MATERIALS AND METHODS : Seven patients with T3 or T4 lung cancer and mediastinal node enlargement who previously received radiotherapy were studied. All patients underwent virtual simulation retrospectively with the previous treatment planning CTs. Initial radiotherapy plans were designed to deliver 40 Gy to the primary tumor and involved nodal regions with the conventional anterior / posterior opposed beams. Two radiation dose levels, 24 and 30 Gy, were used for the boost radiotherapy plans, and 4 different boost methods (a three dimensional conformal radiotherapy (3DCRT), 5, 7, and 9-beams IMRT) were applied to each dose level. The goals of the boost plans were to deliver the prescribed radiation dose to 95% of the planning target volume (PTV) and minimize the volumes of the normal lungs and spinal cord irradiated above their tolerance doses. Dose distributions in the PTVs and lungs, according to the four types of boost plans, were compared in the boost and sum plans, respectively. RESULTS : The percentage of lung volumes irradiated >20 Gy (V20) were reduced significantly in the IMRT boost plans compared with the 3DCRT boost plans at the 24 and 30 Gy dose levels (p=0.007 and 0.031 respectively). Mean lung doses according to the boost methods were not different in the 24 and 30 Gy boost plans. The conformity indexes (CI) of the IMRT boost plans were lower than those of the 3DCRT plans in the 24 and 30 Gy plans (p=0.001 in both). For the sum plans, there was no difference of the dose distributions in the PTVs and lungs according to the boost methods. CONCLUSION : In the boost plans the V20s and CIs were reduced significantly by the IMRT plans, but in the sum plans the effects of IMRT to the dose distributions in the tumor and lungs, like CI and V20, were offset. Therefore, in order to keep the beneficial effect of IMRT in radiotherapy for lung cancer, it would be better to use IMRT as a whole treatment plan rather than as a boost treatment
Humans ; Lung Neoplasms* ; Lung* ; Radiotherapy ; Radiotherapy, Conformal ; Retrospective Studies ; Spinal Cord

PURPOSE: A hybrid-dynamic conformal arc therapy (HDCAT) technique consisting of a single half-rotated dynamic conformal arc beam and static field-in-field beams in two directions was designed and evaluated in terms of dosimetric benefits for radiotherapy of lung cancer. MATERIALS AND METHODS: This planning study was performed in 20 lung cancer cases treated with the VERO system (BrainLAB AG, Feldkirchen, Germany). Dosimetric parameters of HDCAT plans were compared with those of three-dimensional conformal radiotherapy (3D-CRT) plans in terms of target volume coverage, dose conformity, and sparing of organs at risk. RESULTS: HDCAT showed better dose conformity compared with 3D-CRT (conformity index: 0.74 ± 0.06 vs. 0.62 ± 0.06, p < 0.001). HDCAT significantly reduced the lung volume receiving more than 20 Gy (V20: 21.4% ± 8.2% vs. 24.5% ± 8.8%, p < 0.001; V30: 14.2% ± 6.1% vs. 15.1% ± 6.4%, p = 0.02; V40: 8.8% ± 3.9% vs. 10.3% ± 4.5%, p < 0.001; and V50: 5.7% ± 2.7% vs. 7.1% ± 3.2%, p < 0.001), V40 and V50 of the heart (V40: 5.2 ± 3.9 Gy vs. 7.6 ± 5.5 Gy, p < 0.001; V50: 1.8 ± 1.6 Gy vs. 3.1 ± 2.8 Gy, p = 0.001), and the maximum spinal cord dose (34.8 ± 9.4 Gy vs. 42.5 ± 7.8 Gy, p < 0.001) compared with 3D-CRT. CONCLUSIONS: HDCAT could achieve highly conformal target coverage and reduce the doses to critical organs such as the lung, heart, and spinal cord compared to 3D-CRT for the treatment of lung cancer patients.
Heart ; Humans ; Lung Neoplasms ; Lung ; Organs at Risk ; Radiotherapy ; Radiotherapy, Conformal ; Spinal Cord

As the main type of lung cancer, non-small cell lung cancer (NSCLC) is a common cancer which is characterized by low 5-year survival rate and worse prognosis. Nowadays, some studies show that the low survival rate and worse prognosis are due to the resistance to radiotherapy caused by circRNA. Therefore, to find out the relationship between circRNA and radiotherapy resistance of NSCLC was imoprtant. According to research the relevant literatures, the relationship between circRNA and radiotherapy resistance of NSCLC was explored. CircRNA plays an important role in the invasion, metastasis, proliferation and treatment resistance of NSCLC. The radiation resistance of tumor cells induced by circRNA has become a crucial problem in radiotherapy. CircRNA plays an important role in the radiotherapy resistance of NSCLC.
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Carcinoma, Non-Small-Cell Lung/radiotherapy* ; Cell Proliferation ; Humans ; Lung Neoplasms/radiotherapy* ; MicroRNAs ; RNA, Circular