Low-glucose/High-fat Intake Dietary Regimen as a Tool for Empowering Diagnostic Accuracy of 2-[18F]FDG PET/CT in Lepidic-predominant Growth Lung Adenocarcinoma

Lepidic-predominant lung adenocarcinoma is a subtype of non-small cell lung cancer characterized by relatively low glucose metabolism, which may reduce the sensitivity of standard 2-\[18F\]FDG PET/CT. Preclinical and translational evidence suggests that a ketogenic diet may enhance tumour FDG uptake in this setting. This prospective proof-of-concept interventional study will enroll approximately 30 adults with CT evidence of a pulmonary nodule suspicious for LPA or histologically confirmed LPA. After informed consent, participants will undergo an initial dietary assessment and receive an individualized ketogenic diet plan. The ketogenic diet will be followed for 7 days prior to FDG PET/CT. On the day of imaging, participants will undergo a second dietary evaluation, laboratory testing, urinalysis, and PET/CT. PET/CT images will be reviewed independently by two board-certified nuclear medicine physicians. Diagnostic performance will be assessed using visual and semiquantitative PET parameters, with histopathological diagnosis as the reference standard. Study-level results will also be compared with values reported in the literature and with a matched retrospective cohort from the same institution.