Three-dimensional Radiotherapy Research Articles

A Generalized Selectively Relaxed Matrix Splitting Preconditioning Strategy for Three-Dimensional Flux-Limited Multi-Group Radiation Diffusion Equations

A Generalized Selectively Relaxed Matrix Splitting Preconditioning Strategy for Three-Dimensional Flux-Limited Multi-Group Radiation Diffusion Equations

Simulating X-Ray Reverberation in the Ultraviolet-emitting Regions of Active Galactic Nuclei Accretion Disks with Three-dimensional Multifrequency Radiation Magnetohydrodynamic Simulations

Active galactic nuclei (AGN) light curves observed with different wave bands show that the variability in longer wavelength bands lags the variability in shorter wavelength bands. Measuring these lags, or reverberation mapping, is used to measure the radial temperature profile and extent of AGN disks, typically with a reprocessing model that assumes X-rays are the main driver of the variability in other wavelength bands. To demonstrate how this reprocessing works with realistic accretion disk structures, we use 3D local shearing box multifrequency radiation magnetohydrodynamic simulations to model the UV-emitting region of an AGN disk, which is unstable to the magnetorotational instability and convection. At the same time, we inject hard X-rays (>1 keV) into the simulation box to study the effects of X-ray irradiation on the local properties of the turbulence and the resulting variability of the emitted UV light curve. We find that disk turbulence is sufficient to drive intrinsic variability in emitted UV light curves and that a damped random walk model is a good fit to this UV light curve for timescales >5 days. Meanwhile, X-ray irradiation has negligible impact on the power spectrum of the emitted UV light curve. Furthermore, the injected X-ray and emitted UV light curves are only correlated if there is X-ray variability on timescales >1 day, in which case we find a correlation coefficient r = 0.34. These results suggest that if the opacity for hard X-rays is scattering dominated as in the standard disk model, hard X-rays are not the main driver of reverberation signals.

3D non-LTE modeling of the stellar center-to-limb variation for transmission spectroscopy studies

Context. Transmission spectroscopy is one of the most powerful techniques used to characterize transiting exoplanets, since it allows for the abundance of the atomic and molecular species in the planetary atmosphere to be measured. However, stellar lines may bias the determination of such abundances if their center-to-limb variations (CLVs) are not properly accounted for. Aims. This paper aims to show that three-dimensional (3D) radiation hydrodynamic models and the assumption of non-local ther-modynamic equilibrium (non-LTE) line formation are required for an accurate modeling of the stellar CLV of the Na I D1 and K I resonance lines on transmission spectra. Methods. We modeled the CLV of the Na I D1 and K I resonance lines in the Sun with 3D non-LTE radiative transfer. The synthetic spectra were compared to solar observations with high spatial and spectral resolution, including new data collected with the CRISP instrument at the Swedish 1-m Solar Telescope between µ = 0.1 and µ = 1.0. Results. Our 3D non-LTE modeling of the Na I D1 resonance line at 5896 Å and the K I 7699 Å resonance line in the Sun is in good agreement with the observed CLV in the solar spectrum. Moreover, the simulated CLV curve for a Jupiter-Sun system inferred with a 3D non-LTE analysis shows significant differences from the one obtained from a 1D atmosphere. The latter does indeed tend to overestimate the amplitude of the transmission curve by a factor that is on the same order of magnitude as a planetary absorption depth (i.e., up to 0.2%). Conclusions. This work highlights the fact that to correctly characterize exoplanetary atmospheres, 3D non-LTE synthetic spectra ought to be used to estimate the stellar CLV effect in transmission spectra of solar-like planet hosts. Moreover, since different spectral lines show different CLV curves for the same geometry of the planet-star system, it is fundamental to model the CLV individually for each line of interest. The work will be extended to other lines and FGK-type stars, allowing for synthetic high-resolution spectra to mitigate the stellar contamination of low-resolution planetary spectra, for example, those drawn from JWST.

Determination of Planning Target Volume in Radiotherapy - A Review

Treatment volume definitions used in three-dimensional radiotherapy treatment planning are essential in advancing treatment modalities. However, there are many sources of error during the treatment preparation and execution that limit the accuracy. Consequently, a safety margin is required to add to the target to ensure that the planned dose is delivered to the target. Multiple margins surround the tumour to reduce positional inaccuracy, such as Clinical Target Volume (CTV), Planning Target Volume (PTV), etc. The International Commission of Units and Measurement (ICRU) recommended margins in 1978. It was later reviewed in Reports 50 and 62 of ICRU, providing information on margins covering gross volume, clinical volume, and critical structures that should be eliminated as feasible. This article aims to discuss various techniques and methods that various authors have created. Keywords: Margin, Errors, GTV, CTV, ITV, PTV, ICRU 50, ICRU 62, Radiotherapy.

Modeling investigation of wave-induced longshore current distribution patterns on barred beaches

A three-dimensional coupled wave-current model was employed to investigate the wave-induced longshore currents on barred beaches. The modeling system was developed by coupling the finite-volume community ocean model (FVCOM) and the simulating waves nearshore (SWAN) model to fully describe wave-current interactions in the nearshore region. The three-dimensional radiation stress, surface rollers and wave-enhanced turbulent mixing were incorporated as the major wave effects on currents. The model was first evaluated against data collected from multiple sets of laboratory experiments. Diagnostic simulations demonstrated that the contributions of the wave rollers and wave-induced mixing, in addition to the radiation stress, were important for ensuring accurate calculations. Then, the longshore current patterns on barred beaches were investigated through simulations of a series of test cases under controlled conditions. The cross-shore distribution of wave-induced longshore currents, which predominantly occurred within the barred beach surf zone, usually exhibited bimodal characteristics. The maximum peak longshore current velocity was positively correlated with the incident wave height and period. As the bar height and width increased, the first velocity peak of the longshore current strengthened, while the second peak weakened. In most cases, the maximum longshore current velocity on a barred beach coincided with the first peak, which could occur anywhere from the bar-trough region to the bar-crest region, depending on the wave and bar heights. This finding could be used to clarify the cross-shore location discrepancies in the maximum peak longshore current velocity reported in previously published studies.

Three-dimensional radiation hydrodynamics simulations of wandering intermediate-mass black holes considering the anisotropic radiation and dust sublimation

ABSTRACT By performing three-dimensional radiation hydrodynamics simulations, we study Bondi–Hoyle–Lyttleton accretion on to intermediate-mass black holes (BHs) wandering in the dusty gas. Here, we take into account the anisotropic radiation feedback and the sublimation of dust grains. Our simulations show that when the relative velocity between the BH and the gas is small ($\sim 20\rm\, km~s^{-1}$) and gas density is $\sim 10^4 \rm cm^{-3}$, the gas mainly accretes from near the equatorial plane of the accretion disc at a time-averaged rate of 0.6 per cent of the Bondi–Hoyle–Lyttleton rate. An ionized region like two spheres glued together at the equatorial plane is formed, and the dense shock shell appears near the ionization front. The BH is accelerated at $\sim 10^{-8}\, \rm cm~s^{-2}$ due to the gravity of the shell. For denser gas ($\sim 10^6 \rm cm^{-3}$), the time-averaged accretion rate is also 0.6 per cent of the Bondi–Hoyle–Lyttleton rate. However, the BH is decelerated at $\sim 10^{-7}\, \rm cm~s^{-2}$ due to gravity of the dense downstream gas although the dense shock shell appears upstream. Our simulations imply that intermediate-mass BHs in the early universe keep floating at $\gtrsim {\rm several}\, 10\, \rm km~s^{-1}$ without increasing mass in interstellar gas with density of $\sim 10^4\, \rm cm^{-3}$, and slow down and grow into supermassive BHs in galaxies with the density of $\sim 10^6\, \rm cm^{-3}$.

A Review of Silo Temperature Field Studies

Silo is a large thin-walled structure, due to the operation period will be affected by different temperatures, such as sunshine temperature difference, seasonal temperature difference and the temperature difference between inside and outside the silo wall, of which the most influential is the sunshine temperature difference, silo due to the unevenness of the temperature distribution is prone to stress concentration and more likely to occur damage. This paper briefly introduces the three-dimensional heat transfer theory and ASHRAE solar radiation model, and discusses in detail the research progress of different experts and scholars at China and abroad on the temperature effect of silos. Finally, it is concluded that there are fewer temperature regulations in China codes, and there is a need to develop a perfect temperature theory to prevent silos from damage caused by temperature inhomogeneity.

Investigation on the burning behaviors of the combustible ceiling with the impingement of an incipient fire source

This paper presents experimental and theoretical research on ceiling jet, burn-through, and flame spread behaviors of the combustible ceiling with the impingement of an incipient fire source. Medium-density fiberboard was utilized as the combustible ceiling in experiments, and the ceiling height above the fire source was varied. The flame radial length (rf), ceiling surface temperature, flame shape and spread rate after burn-through, and radiative heat flux were measured. Results showed that rf beneath the combustible ceiling was significantly longer than that of the non-combustible ceiling. Theoretical analysis was conducted for rf based on energy distribution, and an expression of rf beneath combustible ceiling was proposed. The burn-through behavior of the combustible ceiling was explored by combining the ceiling temperature, small-sized experiment and Fourier law. The advancement of char front along the ceiling thickness was calculated, which was the key point during burn-through. Upper surface flame spread in a circular shape after burn-through, and an expression of spread rate was obtained. A three-dimensional radiation model was adopted to calculate the radiative heat flux received by the unburned ceiling surface during the dynamic flame spread process, the calculated results agreed well with the experimental data.

Biomedical advances and future prospects of high-precision three-dimensional radiotherapy and four-dimensional radiotherapy.

Biomedical advances of external-beam radiotherapy (EBRT) with improvements in physical accuracy are reviewed. High-precision (±1 mm) three-dimensional radiotherapy (3DRT) can utilize respective therapeutic open doors in the tumor control probability curve and in the normal tissue complication probability curve instead of the one single therapeutic window in two-dimensional EBRT. High-precision 3DRT achieved higher tumor control and probable survival rates for patients with small peripheral lung and liver cancers. Four-dimensional radiotherapy (4DRT), which can reduce uncertainties in 3DRT due to organ motion by real-time (every 0.1-1 s) tumor-tracking and immediate (0.1-1 s) irradiation, have achieved reduced adverse effects for prostate and pancreatic tumors near the digestive tract and with similar or better tumor control. Particle beam therapy improved tumor control and probable survival for patients with large liver tumors. The clinical outcomes of locally advanced or multiple tumors located near serial-type organs can theoretically be improved further by integrating the 4DRT concept with particle beams.

Three Dimensional Natures of Massive Star Envelopes

In this paper, we review our current understanding of the outer envelope structures of massive stars based on three-dimensional (3D) radiation hydrodynamic simulations. We briefly summarize the fundamental issues in constructing hydrostatic one-dimensional (1D) stellar evolution models when stellar luminosity approaches the Eddington value. Radiation hydrodynamic simulations in 3D covering the mass range from 13M⊙ to 80M⊙ always find a dynamic envelope structure with the time-averaged radial profiles matching 1D models with an adjusted mixing-length parameter when convection is subsonic. Supersonic turbulence and episodic mass loss are generally found in 3D models when stellar luminosity is super-Eddington locally due to the opacity peaks and convection being inefficient. Turbulent pressure plays an important role in supporting the outer envelope, which makes the photosphere more extended than predictions from 1D models. Massive star lightcurves are always found to vary with a characteristic timescale consistent with the thermal time scale at the location of the iron opacity peak. The amplitude of the variability as well as the power spectrum can explain the commonly observed stochastic low-frequency variability of mass stars observed by TESS over a wide range of parameters in an HR diagram. The 3D simulations can also explain the ubiquitous macro-turbulence that is needed for spectroscopic fitting in massive stars. Implications of 3D simulations for improving 1D stellar evolution models are also discussed.

IMRT in the treatment of locally advanced or inoperable NSCLC in the pre-durvalumab era: clinical outcomes and pattern of relapses, experience from the Oscar Lambret Center.

Intensity-modulated conformal radiotherapy (IMRT) has become the technique of choice for the treatment of locally advanced or inoperable non-small cell lung cancer (NSCLC). Nevertheless, this technique presents dosimetric uncertainties, particularly in treating moving targets such as pulmonary neoplasms. Moreover, it theoretically increases the risk of isolated nodal failure (INF) due to reduced incidental irradiation. The objective of this study was to evaluate the efficacy and safety of IMRT in patients with inoperable NSCLC and to describe the pattern of relapses. Patients with locally advanced NSCLC treated with radiotherapy and chemotherapy between 2015 and 2018 at the Oscar Lambret Center were retrospectively included in the study. Overall and progression-free survival were estimated using the Kaplan-Meier method. The cumulative incidence of the different components of relapse was estimated using the Kalbfleisch and Prentice method. Prognostic factors for relapse/death were investigated using the Cox model. A comparison with literature data was performed using a one-sample log-rank test. Seventy patients were included, and 65 patients (93%) had stage III disease. All the patients received chemotherapy, most frequently with cisplatin and navelbine. The dose received was 66 Gy administered in 33 fractions. The median follow-up and survival were 49.1 and 39.1 months, respectively. A total of 35 deaths and 43 relapses, including 29 with metastatic components, were reported. The overall survival rates at 1 and 2 years were 80.2% (95% confidence interval 68.3%-88.0%) and 67.2% (95% confidence interval 54.2%-77.3%), respectively. Locoregional relapse was observed in 14 patients, including two INF, one of which was located in the lymph node area adjacent to the clinical target volume. Median relapse-free survival was 15.2 months. No variable was statistically associated with the risk of relapse/death in multivariate analysis. Seven patients (10%) experienced grade 3 or higher toxicity. The use of IMRT for locally advanced or inoperable NSCLC led to favorable long-term clinical outcomes. The rate of locoregional relapse, particularly isolated lymph node failure, was low and comparable with that of the three-dimensional radiotherapy series, as was the rate of early and late toxicities.

Augmented reality in orthodontics for bracket placement using conventional mobile devices: Technical note

Improving bracket placement accuracy through computer-aided design and a bracket navigation set supported by augmented reality (AR). A technical workflow was developed for implementing AR-assisted orthodontic bracket positioning through a smartphone application. This innovative approach eliminates the need for three-dimensional radiation imaging or physical guides, making it a safe and convenient option for clinical use by overlapping the digitally planned bracket position over the patient clinical crown for a precise recommendation of bracket positioning. It was found that it is achievable and can be easily recognized from all view angles, and this proves that new techniques with new opportunities could be considered. AR smartphone applications can potentially be used for the accurate placement of dental brackets; thus, such applications show promise for use in the field of orthodontics.

Radiomics based predictive modeling of rectal toxicity in prostate cancer patients undergoing radiotherapy: CT and MRI comparison.

Rectal toxicity is one of the common side effects after radiotherapy in prostate cancer patients. Radiomics is a non-invasive and low-cost method for developing models of predicting radiation toxicity that does not have the limitations of previous methods. These models have been developed using individual patients' information and have reliable and acceptable performance. This study was conducted by evaluating the radiomic features of computed tomography (CT) and magnetic resonance (MR) images and using machine learning (ML) methods to predict radiation-induced rectal toxicity. Seventy men with pathologically confirmed prostate cancer, eligible for three-dimensional radiation therapy (3DCRT) participated in this prospective trial. Rectal wall CT and MR images were used to extract first-order, shape-based, and textural features. The least absolute shrinkage and selection operator (LASSO) was used for feature selection. Classifiers such as Random Forest (RF), Decision Tree (DT), Logistic Regression (LR), and K-Nearest Neighbors (KNN) were used to create models based on radiomic, dosimetric, and clinical data alone or in combination. The area under the curve (AUC) of the receiver operating characteristic curve (ROC), accuracy, sensitivity, and specificity were used to assess each model's performance. The best outcomes were achieved by the radiomic features of MR images in conjunction with clinical and dosimetric data, with a mean of AUC: 0.79, accuracy: 77.75%, specificity: 82.15%, and sensitivity: 67%. This research showed that as radiomic signatures for predicting radiation-induced rectal toxicity, MR images outperform CT images.

A Bright First Day for Tidal Disruption Events

Stream–stream collision may be an important prepeak energy dissipation mechanism in tidal disruption events (TDEs). We perform local three-dimensional radiation hydrodynamic simulations in a wedge geometry including the gravity to study stream self-crossing with an emphasis on resolving the collision and following the subsequent outflow. We find that the collision can contribute to prepeak optical emissions by converting ≳5% of the stream kinetic energy to radiation, yielding prompt emission of ∼1042−44 erg s−1. The radiative efficiency is sensitive to stream mass fallback rates and strongly depends on the downstream gas optical depth. Even for a sub-Eddington (10%) mass fallback rate, the strong radiation pressure produced in the collision can form a local super-Eddington region near the collision site, where a fast, aspherical outflow is launched. A higher mass fallback rate usually leads to more optically thick outflow and lower net radiative efficiency. For , the estimated photosphere size of the outflow can expand by 1–2 orders of magnitude, reaching ∼1014 cm. The average gas temperature at this photospheric surface is a few × 104 K, roughly consistent with inferred prepeak photosphere properties for some optical TDEs. We find that the dynamics is sensitive to the collision angle and radius, but the radiative efficiency or outflow properties show more complex dependency than is often assumed in ballistic models.

Turbulence-supported Massive Star Envelopes

The outer envelopes of massive (M ≳ 10 M ⊙) stars exhibit large increases in opacities from forests of lines and ionization transitions (particularly from iron and helium) that trigger near-surface convection zones. One-dimensional (1D) models predict density inversions and supersonic motions that must be resolved with computationally intensive three-dimensional (3D) radiation hydrodynamic (RHD) modeling. Only in the last decade have computational tools advanced to the point where ab initio 3D models of these turbulent envelopes can be calculated, enabling us to present five 3D RHD Athena++ models (four previously published and one new 13 M ⊙ model). When convective motions are subsonic, we find excellent agreement between 3D and 1D velocity magnitudes, stellar structure, and photospheric quantities. However, when convective velocities approach the sound speed, hydrostatic balance fails as the turbulent pressure can account for 80% of the force balance. As predicted by Henyey, we show that this additional pressure support leads to a modified temperature gradient, which reduces the superadiabaticity where convection is occurring. In addition, all five models display significant overshooting from the convection in the Fe convection zone. As a result, the turbulent velocities at the surface are indicative of those in the Fe zone. There are no confined convection zones as seen in 1D models. In particular, helium convection zones seen in 1D models are significantly modified. Stochastic low-frequency brightness variability is also present in the 13 M ⊙ model with comparable amplitude and characteristic frequency to observed stars.

Introduction to EarthCARE synthetic data using a global storm-resolving simulation

Abstract. Pre-launch simulated satellite data are useful to develop retrieval algorithms and to facilitate the rapid release of retrieval products after launch. Here we introduce the Japanese Aerospace Exploration Agency's (JAXA) EarthCARE synthetic data based on simulations using a 3.5 km horizontal-mesh global storm-resolving model. Global aerosol transport simulation results are added for aerosol retrieval developers. Synthetic data were produced corresponding to the four EarthCARE instrument sensors, namely a 94 GHz cloud-profiling radar (CPR), a 355 nm atmospheric lidar (ATLID), a seven-channel multispectral imager (MSI), and a broadband radiometer (BBR). JAXA EarthCARE synthetic data include a standard product with data for two orbits and a research product with shorter frames and more detailed instrument settings. In the research products, random errors in the CPR are considered based on the observation window, and noise in ATLID signals are added using a noise simulator. We consider the spectral misalignment effect of the visible and near-infrared MSI channels based on response functions depending on the angle from the nadir. We introduce plans for updating the JAXA EarthCARE synthetic data using large eddy simulation model data and the implementation of a three-dimensional radiation model. The JAXA EarthCARE synthetic data are available publicly.

Three-dimensional analysis of THz radiation mechanisms in interaction of arbitrarily polarized multi-color laser pulses and obliquely magnetized plasma

Three-dimensional THz radiation generation via wave-mixing and photo-current mechanisms of multi-color femtosecond laser fields in obliquely magnetized plasma for various laser polarization states is considered. The main motive behind present study has been to investigate the development of more efficient and versatile THz radiation generation for a range of applications through a comprehensive mechanism describing the entire THz frequency band. Two and three-color laser waves interactions with plasma electrons results in a transverse nonlinear current density which causes THz radiation generation. Variation of THz electric field under different laser polarizations is examined analytically and numerically. The impacts of the applied oblique magnetic field and the field oblique angle on the THz electric field for both wave mixing and photo-current schemes are studied and result are compared. A method to implement THz radiation for special applications was developed showing that the external magnetic field is crucial in controlling plasma dynamics. The waveforms of THz angular distribution in forward direction are examined and the impact of different harmonics, various polarization states, external magnetic field, oblique angle of the applied external magnetic field, and the length of plasma on generated waveforms is considered. Based on the results of study, laser harmonics and applied external magnetic field increase electrons current density, leading to enhancement of radiation power without change in directionality diagram. These findings are in close agreement with experimental results.

Comparison of Dose Distribution to Target Volume and Organs at Risk using 3D CRT, IMRT, and VMAT Techniques in Glioblastoma Cases

The average lifetime risk of secondary cancer after irradiating glioblastoma radiation therapy to healthy organs shows that the technique of volumetric modulated arc therapy (VMAT) has a smaller risk of developing secondary cancer compared to intensity modulated radiation therapy (IMRT) and three-dimensional radiation therapy (3DCRT). Parameters of dose distribution, namely the target volume and dose received by the organs at risk (OAR), are used to compare these three techniques. The distribution of doses from TPS results in the form of DVH and isodose in the 3D CRT, IMRT, and VMAT techniques shows that the distribution of doses to healthy organs around the glioblastoma irradiation area is in the safe category and is still within tolerance limits. With VMAT, the PTV and CTV dose results were more optimal compared to the 3D CRT and IMRT techniques. 3D CRT showed a PTV dose value of 5551.8 cGy and a CTV of 5515.3 cGy. IMRT shows a PTV dose value of 6035.0 cGy and a CTV of 6018.8 cGy. VMAT shows PTV dose values of 6101.8 cGy and CTV of 6044.7 cGy. It can be seen that the distribution of doses to healthy organs in general in the VMAT technique is more optimal than the IMRT and 3D CRT techniques in protecting OAR.

An Inductively Coupled Plasma System for Investigating Spectropolarimetric Responses of Solar Plasmas to Anisotropic Fields

High precision measurements and accurate modeling of atomic polarization under three-dimensional radiation transfer are crucial to understand the structures of magnetized solar plasmas. To develop and validate spectropolarimetric measurements and analyses, we set up an inductively coupled plasma (ICP) generator designed especially for ∼1-eV plasmas interacting with radiation and weak magnetic fields. The device was put in front of the focal plane of the Horizontal Spectrograph of the Domeless Solar Telescope at Hida Observatory of Kyoto University. In helium discharges, the typical electron temperature, electron density, and helium column density of the ICP are comparable values to those of solar prominences, and the direct comparison of spectra shows almost the same opacity at He I 1083 nm. Magnetic and radiation fields were introduced to the ICP, and the system successfully reproduced reasonable spectropolarimetric signals as compared with those from the solar prominences.

Quality of life and survival outcomes of patients with inoperable esophageal squamous cell carcinoma after definitive radiation therapy: A multicenter retrospective observational study in China from 2015 to 2016

ObjectivesTo investigate the health-related quality of life (HRQL) of long-term survivors of inoperable esophageal squamous cell carcinoma (ESCC) treated with definitive radiation therapy, the real-world trends in the use of advanced radiation techniques, and their impact on the survival outcomes of ESCC patients. MethodsIn this multicenter retrospective observational study, the medical records related to demographics and treatment of ESCC patients who were treated with definitive radiation therapy at 14 provincial hospitals in China from 1 January 2015 to 31 December 2016 were analyzed. A HRQL questionnaire was completed by survivors and collected by doctors at the final follow-up. The difference in quality of life between patients with or without recurrence was compared using the Wilcoxon–Mann–Whitney test. Overall survival (OS) was estimated using the Kaplan–Meier method and the group differences were assessed by unstratified log-rank test. The Cox proportional hazards model with Efron's method of tie handling was used to calculate the risk factors for OS. ResultsThe data of a total of 3,308 patients were collected for this study, 248 were excluded because of missing data, and a final of 3,060 patients were included in the analysis. Most patients (2,901; 94.8%) received intensity-modulated radiotherapy (IMRT)/volumetric-modulated arc therapy (VMAT)/tomotherapy (TOMO). The 5-year OS rate was 30%. Patients who received either two-dimensional radiotherapy (2DRT; HR, 2.43 [95% CI, 1.70–3.47]; P < 0.001) or three-dimensional radiotherapy (3DRT; HR, 1.45 [95% CI, 1.14–1.84]; P = 0.003) had a significantly increased risk of death compared to those who received IMRT/VMAT/TOMO. Of the 716 (23.4%) long-term survivors who completed the HRQL questionnaire, nearly 70% patients were still able to swallow normally or almost normally, and >80% patients did not experience weight loss. Nearly 80% patients found life very enjoyable or were fairly enjoying life. ConclusionsThis large, multicenter retrospective study on ESCC patients who received definitive radiation therapy found that most ESCC survivors are satisfied with their quality of life. Most patients received advanced radiation technology. Patients who received either 2DRT or 3DRT had a significantly increased risk of death compared to those who received advanced radiation technology.