Validity of Current Stereotactic Body Radiation Therapy Dose Constraints for Aorta and Major Vessels

Xue, Jiangyu; Kubicek, Gregory J.; Patel, Ashish; Goldsmith, Benjamin; Asbell, Sucha O.; LaCouture, Tamara

doi:10.1016/j.semradonc.2015.11.001

Cited by 27 publications

(22 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A great vessel is deemed as a dose-limiting organ when lesions are given hypofractionated or stereotactic body radiotherapy (SBRT) [ 17 ]. Some researchers thought there were greater risks of severe hemoptysis and early mortality among patients who had severe PA invasion during or after radiotherapy.…”

Section: Discussionmentioning

confidence: 99%

Is pulmonary artery a dose-limiting organ at risk in non-small cell lung cancer patients treated with definitive radiotherapy?

Sun

et al. 2017

Radiat Oncol

View full text Add to dashboard Cite

PurposeOur previous study suggested that some pulmonary artery (PA) dosimetric parameters were associated with mortality in unresectable non-small cell lung cancer (NSCLC) treated with definitive radiotherapy. The present study aims to analyze the impact of both PA and heart dosimetric parameters on survival of patients with NSCLC treated with definitive conventional fractionated radiotherapy (CFRT) in another independent research center and further determine whether the PA should be considered a dose-limiting organ at risk (OAR) for patients receiving thoracic CFRT.MethodsWe performed a retrospective analysis of successive patients with medically inoperable or unresectable NSCLC treated with definitive radiotherapy or chemoradiotherapy from August 2010 to September 2014. Clinical and pathological information, PA and heart dosimetric factors, and follow-up data were collected from each patient’s records and evaluated as potential prognostic factors for survival. Survival probabilities were estimated by the Kaplan-Meier method and compared by the log rank test. Cox proportional hazards regression models were performed to determine the independent predicators of survival. The optimal cutoff points of continuous dosimetric variables were determined by Youden index in receiver operating characteristic (ROC) analysis.ResultsThis study analyzed the records of 141 patients, 50.4% had adenocarcinoma, 71.6% had stage III disease, and 55% patients received concurrent chemoradiotherapy. Radiation dose ranged from 60 to 76 Gy in 30–38 fractions. Median follow up was 16.9 months. Median overall survival (OS) was 20.5 months (95% confidence interval [CI] 10.3-30.7 months), and 1-, 2-, 3-year OS rates were 75.2%, 58.2% and 56%, respectively. Univariate and multivariate analysis showed that Karnofsky Performance Status (KPS) score, Charlson’s Comorbidity Index (CCI), T and N stage, PA invasion grade and the percentage of PA volume that received 40 to 55 Gy (PA V40-55) were significantly associated with OS. No significant associations were found between heart dosimetric factors and OS. Median OS of patients with PA invasion grade 0, 1, 2, and 3 were 41.8, 27.8, 12.7 and 7.5 months, respectively (P < 0.001). PA V40, V45, V50 and V55, using thresholds of 80%, 68%, 45%, and 32%, respectively, were independent predictors for OS.ConclusionsPA invasion grade and PA V40-55 appear associated with OS in patients with NSCLC treated with definitive CFRT. We propose that PA be considered as a dose-limiting OAR for such patients.

show abstract

Section: Discussionmentioning

confidence: 99%

Is pulmonary artery a dose-limiting organ at risk in non-small cell lung cancer patients treated with definitive radiotherapy?

Sun

et al. 2017

Radiat Oncol

View full text Add to dashboard Cite

show abstract

“…Xue et al ( 47 ) focused the study on major vessel toxicity in order to predict the radiation-induced aneurysm (G3-5) and used the logistic model in a large internal/external cohort within the LQ framework. Aorta dose–volume response model for V25 Gy, D4 cc, D1 cc, D0.5 cc, and Dmax have been calculated along with the DVH Risk Map, useful to compare literature constraints with predictions for an individual patient.…”

Section: Resultsmentioning

confidence: 99%

Radiobiological Optimization in Lung Stereotactic Body Radiation Therapy: Are We Ready to Apply Radiobiological Models?

et al. 2018

View full text Add to dashboard Cite

Lung tumors are often associated with a poor prognosis although different schedules and treatment modalities have been extensively tested in the clinical practice. The complexity of this disease and the use of combined therapeutic approaches have been investigated and the use of high dose-rates is emerging as effective strategy. Technological improvements of clinical linear accelerators allow combining high dose-rate and a more conformal dose delivery with accurate imaging modalities pre- and during therapy. This paper aims at reporting the state of the art and future direction in the use of radiobiological models and radiobiological-based optimizations in the clinical practice for the treatment of lung cancer. To address this issue, a search was carried out on PubMed database to identify potential papers reporting tumor control probability and normal tissue complication probability for lung tumors. Full articles were retrieved when the abstract was considered relevant, and only papers published in English language were considered. The bibliographies of retrieved papers were also searched and relevant articles included. At the state of the art, dose–response relationships have been reported in literature for local tumor control and survival in stage III non-small cell lung cancer. Due to the lack of published radiobiological models for SBRT, several authors used dose constraints and models derived for conventional fractionation schemes. Recently, several radiobiological models and parameters for SBRT have been published and could be used in prospective trials although external validations are recommended to improve the robustness of model predictive capability. Moreover, radiobiological-based functions have been used within treatment planning systems for plan optimization but the advantages of using this strategy in the clinical practice are still under discussion. Future research should be directed toward combined regimens, in order to potentially improve both local tumor control and survival. Indeed, accurate knowledge of the relevant parameters describing tumor biology and normal tissue response is mandatory to correctly address this issue. In this context, the role of medical physicists and the AAPM in the development of radiobiological models is crucial for the progress of developing specific tool for radiobiological-based optimization treatment planning.

show abstract

“…In all cases, the strict DVH constraints were respected. Interestingly, new constraints based on the dose-response models providing quantitative estimates of risk as a function of dose and volume have been recently proposed [26][27][28]. In the future studies these new constraints need to be validated.…”

Section: Discussionmentioning

confidence: 99%

Stereotactic body radiation therapy for mediastinal lymph node metastases: how do we fly in a ‘no-fly zone’?

et al. 2018

View full text Add to dashboard Cite

Purpose: To evaluate the treatment-induced toxicity (as primary endpoint) and the efficacy (as secondary endpoint) of stereotactic body radiation therapy (SBRT) in the treatment of mediastinal lymph nodes (LNs) in the so-called no-fly zone (NFZ) in cancers with various histology. Material and methods: Forty-two patients were retrospectively analyzed. Institutional dose/volume constraints for organs at risk (OARs) derived by published data were strictly respected. The correlation between treatment-related variables and toxicity was investigated by logistic regression, Chi-squared test or Fisher's exact test. Overall survival (OS), cause-specific survival (CSS), progression-free survival (PFS) and local control (LC) were collected from the follow-up reports. The impact of potential predictive factors on LC, PFS and OS were estimated by Cox proportional-hazard regression. Results: Median follow-up time was 16 months (range 1-41). Four patients had esophageal G1 toxicity. Ten and six patients had G1 and G2 pulmonary toxicity, respectively. Treatment site and irradiation technique were significantly correlated with G ! 2 and G! 1 toxicity, respectively. OS probability at 19 months was 88.3% and corresponded to CSS. LC probability at 16 months was 66.3% (median LC duration: 22 months, range 1-41). Fifteen patients (35.7%) were disease-free at 25 months (median time, range 1-41). The biologically effective dose (BED) and the target dose coverage indexes were significantly correlated with LC. Conclusions: SBRT can be considered as a safe treatment option for selected patients with oligo-metastases/recurrences in the NFZ, if strict dose/volume constraints are applied.

show abstract

Validity of Current Stereotactic Body Radiation Therapy Dose Constraints for Aorta and Major Vessels

Cited by 27 publications

References 14 publications

Is pulmonary artery a dose-limiting organ at risk in non-small cell lung cancer patients treated with definitive radiotherapy?

Is pulmonary artery a dose-limiting organ at risk in non-small cell lung cancer patients treated with definitive radiotherapy?

Radiobiological Optimization in Lung Stereotactic Body Radiation Therapy: Are We Ready to Apply Radiobiological Models?

Stereotactic body radiation therapy for mediastinal lymph node metastases: how do we fly in a ‘no-fly zone’?

Contact Info

Product

Resources

About