FAP and Stroma Imaging – Current and Future Applications

This presentation provides an overview of fibroblast activation protein (FAP)–directed molecular imaging as a novel approach for tumour staging and theranostic decision-making across multiple malignancies. It introduces the biological role of cancer-associated fibroblasts and stromal remodeling in tumour progression and highlights the rationale for FAP-targeted PET imaging. Clinical evidence from prospective trials and comparative imaging studies is discussed, demonstrating the diagnostic performance of FAPI PET across tumour entities, particularly in sarcoma and gastrointestinal cancers, where high tumour-to-background contrast and strong tracer uptake support improved lesion detection and staging accuracy compared with conventional imaging approaches.

The presentation further addresses emerging clinical applications of FAP-directed radioligand therapy (RLT), including safety, dosimetry, and early response outcomes in patients with advanced solid tumours.

• Understand the biological rationale of fibroblast activation protein (FAP) expression in cancer-associated fibroblasts and its relevance as a stromal imaging target across multiple tumour entities.
• Recognize the diagnostic performance and clinical indications of FAPI PET for tumour staging and restaging, particularly in sarcoma and gastrointestinal malignancies.
• Explain the principles of FAP-directed theranostics and summarize current clinical evidence on safety, dosimetry, and response outcomes of FAPI-based radioligand therapy.

• Nuclear medicine physicians, radiologists, medical oncologists, researchers, and experts in the field of oncology and inflammation

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