Comparison of predictive powers of functional and anatomic dosimetric parameters for radiation-induced lung toxicity in locally advanced non-small cell lung cancer

摘要

PurposeTo investigate the predictive value of the perfusion (Q) single-photon emission computed tomography (SPECT)-weighted dose–function histogram (DFH) obtained mid-treatment (mid-Tx) with radiotherapy (RT) for radiation-induced lung toxicity (RILT) in patients with non-small cell lung cancer (NSCLC). Materials and methodsThe study population consisted of NSCLC patients who were undergoing RT treatment and enrolled in prospective imaging studies. Q-SPECT was performed prior to and during RT (at ～40–45?Gy). A baseline dose–volume histogram (DVH) and mid-Tx DVH based on simulation CT as well as a baseline DFH and mid-Tx DFH based on Q-SPECT were calculated. Only patients with stage III NSCLC and visible functional lung (FL) changes on the mid-Tx scan were eligible for this enriched analysis. RILT was graded according to a reported scale. ResultsForty-two stage III NSCLC patients met the criteria for inclusion. The accumulative incidence of grade ≥2 RILT was 31% in this high-risk population. Significant differences in functional metrics such as functional lung volume FV5–FV20 at increments of 5?Gy and functional MLD (FMLD) were observed between patients with and without grade ≥2 RILT (p?