Clinical Research Directory

Computed Tomography-Guided Stereotactic Adaptive Radiotherapy (CT-STAR) for the Treatment of Central and Ultra-Central Early-Stage Non-Small Cell Lung Cancer

This study will evaluate the impact of CT-guided adaptive stereotactic radiotherapy (CT-STAR) to central and ultra-central early-stage non-small cell lung cancers on grade 3 or greater toxicity. Online adaptive radiation therapy was until recently only done clinically on an integrated MRI-guided system, but recently, Varian Medical Systems has created a CT-guided radiotherapy machine capable of online adaptive radiotherapy (ETHOS). The vast majority of stereotactic body radiotherapy (SBRT) for early-stage lung cancers is performed on a CT-guided machine rather than an MRI-guided machine, necessitating the evaluation of adaptive radiotherapy using ETHOS in this population. Historically, the non-adaptive, stereotactic treatment of central and ultra-central thoracic disease has been associated with unacceptable rates of grade 3+ toxicity. This has resulted in widespread adoption of a hypofractionated, less ablative 8-15 day treatment courses, with a baseline, one-year grade 3+ toxicity rate of 20%. Use of CT-STAR with daily, CT-guided plan adaptation to carefully spare adjacent organs-at-risk (OAR) in this setting may enable safe delivery of a shorter (5 fraction) and more ablative radiotherapy course.