Role of 18F-FDG PET/CT in Restrictive Allograft Syndrome After Lung Transplantation

BACKGROUND: Differential diagnosis of phenotypes of chronic lung allograft dysfunction (CLAD) remains troublesome. We hypothesized that F-fluorodeoxyglucose positron emission tomography with computed tomography (F-FDG PET/CT) may help in differential diagnosis of CLAD phenotypes, as it showed promising results regarding diagnosis and prognosis in interstitial lung diseases. METHODS: A monocentric, retrospective study was performed including all lung transplant recipients suffering from bronchiolitis obliterans syndrome (BOS) or restrictive allograft syndrome (RAS) who underwent F-FDG PET/CT scan, in comparison with stable lung transplant recipients. Maximum standardized uptake value (SUVmax) was associated with pulmonary function and survival. Proof-of-concept microCT and glucose transporter-1 staining served as morphologic validation for regions with different SUVmax. RESULTS: Maximum standardized uptake value was higher in RAS (median, 2.6; n = 29) compared with BOS (median, 1.0; n = 15) and stable patients (median, 0.59; n = 8) (P < 0.0001). In RAS, high SUVmax was associated with worse survival after F-FDG PET/CT (P = 0.0004; hazard ratio, 1.82). Forced vital capacity at F-FDG PET/CT inversely correlated with SUVmax (R = -0.40, P = 0.03). MicroCT analysis revealed extensive fibrosis in regions of high SUVmax, with an increased number of glucose transporter-1-positive cells. CONCLUSIONS: F-fluorodeoxyglucose positron emission tomography with CT may noninvasively differentiate RAS from BOS. RAS patients with areas of increased lung metabolism have worse outcome, demonstrating the potential use of F-FDG PET/CT during follow-up after lung transplantation.

Publication year:2019

BOF-keylabel:yes

IOF-keylabel:yes

BOF-publication weight:6

CSS-citation score:1

Authors from:Higher Education

Accessibility:Open