Frontiers in oncology
EQD2-adjusted mean lung dose and symptomatic pneumonitis after thoracic radiotherapy following immune checkpoint inhibitors in lung cancer: a single-center retrospective cohort study
By Li X, Liu L, Zheng N and 6 others.
Abstract
Background
Evidence on pneumonitis after thoracic radiotherapy following immune checkpoint inhibitor (ICI) exposure remains limited. We examined associations with voxel-wise EQD2 mean lung dose (MLDEQD2) and the ICI-radiotherapy interval.
Methods
This single-center retrospective cohort included 98 patients in a 90-day competing-risk analysis of grade ≥2 radiation pneumonitis (CTCAE), comprising 26 pneumonitis events, 70 event-free observations, and two deaths before pneumonitis. Archived DICOM doses were converted voxel-wise using α/β = 3 Gy. Cumulative incidence was estimated using the Aalen-Johansen method, and Fine-Gray regression included continuous MLDEQD2 and treatment interval. Supplementary logistic analyses included 96 patients.