PET Molecular Imaging and Theranostics in Lung Diseases: Making Precision Medicine a Reality

The integration of molecular and anatomic imaging-particularly via modalities such as PET/CT scan, PET/MRI scan, and emerging total-body PET scan-has significantly advanced the detection, characterization, and personalized treatment of both oncological and nononcological pulmonary diseases.

In oncology, 2-deoxy-2-[¹⁸F]fluoro-d-glucose (¹⁸F-FDG) PET/CT scan remains the cornerstone for lung cancer staging and therapeutic monitoring. New radiotracers targeting amino acid metabolism, receptor expression, angiogenesis, and hypoxia enable earlier and more reliable assessment of cell status. Immuno-PET scan and fibroblast activation protein inhibitor (FAPI) PET scan improve lesion detection and treatment stratification, particularly where ¹⁸FDG-PET is limited. These innovations support accurate staging and dynamic treatment response monitoring. Theranostics, where diagnostic molecules confer therapeutic potential, has gained attention for lung neuroendocrine tumors and potentially other tumors. For example, the theranostics pair Gallium-68-DOTATATE and ¹⁷⁷Lu-DOTATATE allow detection and treatment with the same targeting ligand. Beyond oncology, molecular imaging is promising for nononcological lung diseases, particularly interstitial lung diseases. For example, radiolabeled FAPI tracers could noninvasively quantify fibroblast activity, aiding in disease assessment, therapy guidance, and prognosis. Dual-tracer approaches, such as ¹⁸FDG-PET scan and FAPI PET scan, further may refine differentiation between inflammatory and fibrotic components of disease.

Molecular imaging has revolutionized the management of lung disease, allowing earlier detection, more accurate diagnosis, and the advancement of precision medicine. Looking ahead, the future of molecular imaging lies in developing multitracer protocols for comprehensive assessment. In this way, imaging not only informs diagnosis but also guides targeted therapy (theranostics), ultimately supporting the optimization of individualized patient care.