FAP-targeted PET imaging in peritoneal carcinomatosis

Area of Science:

• Oncology
• Nuclear Medicine
• Radiology

Background:

• Peritoneal carcinomatosis significantly impacts prognosis and surgical options for abdominopelvic cancers.
• Conventional imaging like CT/MRI and Fluorine-18([18F])-FDG PET/CT often fail to accurately assess the full extent of peritoneal disease.
• Small, flat, or low-FDG-avid peritoneal implants are particularly challenging to detect with current methods.

Purpose of the Study:

• To evaluate the diagnostic performance of Fibroblast Activation Protein Inhibitor (FAPI) PET/CT for peritoneal carcinomatosis.
• To compare FAPI PET/CT with conventional imaging modalities, specifically FDG PET/CT.
• To assess the potential impact of FAPI PET/CT on clinical decision-making regarding patient management.

Main Methods:

• Review of head-to-head studies and meta-analyses comparing FAPI PET/CT and FDG PET/CT.
• Analysis of imaging characteristics, including tumour uptake and tumour-to-background ratios.
• Assessment of diagnostic sensitivity and impact on the peritoneal cancer index.

Main Results:

• FAPI PET/CT consistently shows higher tumour uptake and tumour-to-background ratios in peritoneal lesions compared to FDG PET/CT.
• FAPI PET/CT demonstrates higher diagnostic sensitivity for detecting peritoneal carcinomatosis than FDG PET/CT.
• Improved mapping of peritoneal disease via FAPI PET/CT leads to a more accurate peritoneal cancer index.

Conclusions:

• FAPI PET/CT represents a significant advancement in imaging peritoneal carcinomatosis, outperforming FDG PET/CT.
• Enhanced visualization of peritoneal metastases with FAPI PET/CT can refine patient selection for surgery and therapies.
• Further prospective trials are needed to establish optimal indications and confirm outcome benefits, addressing current limitations like single-center data and heterogeneous standards.