A Frequently Missed Pulmonary Infarction Clinical and 18F-FDG PET/CT Manifestation of Hilar Tumor-Induced Pulmonary Infarction

Purpose This study aimed to summarize the clinical and F-18-FDG PET/CT manifestations of hilar tumor-induced pulmonary infarction. Methods A retrospective analysis was performed on patients with hilar masses who underwent FDG PET/CT scans between July 2015 and January 2021 and had complete clinical data. Pulmonary infarction was confirmed by concurrent chest CT and imaging follow-up or pathology. Results A total of 58 patients (mean age, 56 [SD, 13] years; 44 males) with 122 infarcts were included in the study. Hilar masses were mostly associated with small cell lung cancer (64%). The most common clinical manifestations were cough (64%) and hemoptysis (36%). Most patients (62%) had multiple pulmonary infarcts. The CT findings of pulmonary infarcts included the Hampton hump (48%) and patchy consolidation (52%). The density of infarcts included bubbly consolidation (61%) and homogenous consolidation (39%). The metabolic activity of 95 infarcts (78%) was higher than lung parenchyma, with the SUVmax of 3.3 (SD, 1.1). The metabolic patterns on PET/CT were rim sign, mismatch between PET and CT, and no metabolism. Pulmonary vein involvement was found in 25 patients (43%), pleural effusion in 22 patients (38%), and the pleural curvilinear sign in 8 patients (14%). Conclusions The clinical manifestations of hilar tumor-induced pulmonary infarction are not specific, and F-18-FDG PET/CT could be an effective diagnostic tool.

Automated summary

The clinical manifestations of hilar tumor-induced pulmonary infarction are not specific, and F-18-FDG PET/CT could be an effective diagnostic tool.