Characterizing Pulmonary Function Test Changes for Patients With Lung Cancer Treated on a 2-Institution, 4-Dimensional Computed Tomography-Ventilation Functional Avoidance Prospective Clinical Trial

Ryan Miller; Richard Castillo; Edward Castillo; Bernard L Jones; Moyed Miften; Brian Kavanagh; Bo Lu; Maria Werner-Wasik; Nader Ghassemi; Joseph Lombardo; Julie Barta; Inga Grills; Chad G Rusthoven; Thomas Guerrero; Yevgeniy Vinogradskiy

doi:10.1016/j.adro.2022.101133

Characterizing Pulmonary Function Test Changes for Patients With Lung Cancer Treated on a 2-Institution, 4-Dimensional Computed Tomography-Ventilation Functional Avoidance Prospective Clinical Trial

Adv Radiat Oncol. 2022 Nov 30;8(2):101133. doi: 10.1016/j.adro.2022.101133. eCollection 2023 Mar-Apr.

Authors

Affiliations

¹ Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania.
² Department of Radiation Oncology, Emory University, Atlanta, Georgia.
³ Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas.
⁴ Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado.
⁵ Department of Thoracic Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania.
⁶ Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan.

Abstract

Purpose: Four-dimensional computed tomography (4DCT)-ventilation-based functional avoidance uses 4DCT images to generate plans that avoid functional regions of the lung with the goal of reducing pulmonary toxic effects. A phase 2, multicenter, prospective study was completed to evaluate 4DCT-ventilation functional avoidance radiation therapy. The purpose of this study was to report the results for pretreatment to posttreatment pulmonary function test (PFT) changes for patients treated with functional avoidance radiation therapy.

Methods and materials: Patients with locally advanced lung cancer receiving chemoradiation were accrued. Functional avoidance plans based on 4DCT-ventilation images were generated. PFTs were obtained at baseline and 3 months after chemoradiation. Differences for PFT metrics are reported, including diffusing capacity for carbon monoxide (DLCO), forced expiratory volume in 1 second (FEV₁), and forced vital capacity (FVC). PFT metrics were compared for patients who did and did not experience grade 2 or higher pneumonitis.

Results: Fifty-six patients enrolled on the study had baseline and posttreatment PFTs evaluable for analysis. The mean change in DLCO, FEV₁, and FVC was -11.6% ± 14.2%, -5.6% ± 16.9%, and -9.0% ± 20.1%, respectively. The mean change in DLCO was -15.4% ± 14.4% for patients with grade 2 or higher radiation pneumonitis and -10.8% ± 14.1% for patients with grade <2 radiation pneumonitis (P = .37). The mean change in FEV₁ was -14.3% ± 22.1% for patients with grade 2 or higher radiation pneumonitis and -3.9% ± 15.4% for patients with grade <2 radiation pneumonitis (P = .09).

Conclusions: The current work is the first to quantitatively characterize PFT changes for patients with lung cancer treated on a prospective functional avoidance radiation therapy study. In comparison with patients treated with standard thoracic radiation planning, the data qualitatively show that functional avoidance resulted in less of a decline in DLCO and FEV₁. The presented data can help elucidate the potential pulmonary function improvement with functional avoidance radiation therapy.

Abstract

Grants and funding