Feasibility Study of Personalized Ultra-fractionated Stereotactic Ablative Radiotherapy (PULSAR) for Cancers of the Central Lung
Summary
The objective of this study is to enhance the safety profile of SAbR in ultra-central tumors of the lung (primary or metastatic) without compromising its effectiveness.
Detailed description
This will be achieved by demonstrating the feasibility of applying adaptive radiation therapy given in PULSAR fractionation and using a 1.5T MR-guided linac system with real-time motion monitoring (Unity, Elekta). The hypothesis is that safety can be improved through: (1) better visualization of tumors, leading to less uncertainty when delineating GTVs; (2) reduced margins for setup, motion, or other sources of uncertainty; and (3) improved normal tissue healing between radiation fractions. To achieve this, we propose a personalized ultrafractionated stereotactic adaptive radiotherapy (PULSAR) delivery schedule, administering 5 fractions total, given as one fraction every 3 weeks (Fig. 3) and using MRI-guided adaptive treatment planning. This study is single arm in nature and in the feasibility phase
Arms & interventions
- RadiationPersonalized Ultra-fractionated stereotactic ablative radiotherapy (PULSAR)
Radiation Therapy Prescription Dose: A dose of 40-50 Gy in 5 fractions prescribed to the PTV will be used for all cases
Outcome measures
Primary
Efficacy- Survivability and response
Rates of overall response will be assessed by RECIST criteria.Efficacy will be compared between PULSAR and historical controls from HILUS using ANOVA and chi-square test. Kaplan-Meier methods will be used to estimate progression-free survival, time to subsequent SABR, overall survival, clinical benefit rate, time to treatment discontinuation, duration of response, and time to new metastases. Response duration will be summarized for patients who responded. Descriptive summary statistics such as median and interquartile range (25% and 75% percentiles) will be used.
Time frame: 4 years
Secondary
Change in Tumor Volume
Time frame: 1 year
Eligibility criteria
Study locations (1)
University of Texas Southwestern Medical Center
Dallas, Texas, 75390