[68Ga]Ga-FAPI Total Body PET/CT for Better and Faster Imaging in Cancer

Specified malignant lesions will be defined and evaluated by a team of specialists on the baseline [68Ga]Ga- FAPI PET/CT scan and the uptake of the FAPI tracer in the lesions will be quantified. The evaluation of the malignant lesions on [68Ga]Ga-FAPI PET/CT will also be compared with a similar lesion evaluation on the [18F]FDG PET/CT (standard imaging). The FAPI-uptake will be reassessed after 12 weeks of ICT by the same team of specialists. Changes in uptake of malignant lesions after 12 weeks of ICT on the [68Ga]Ga-FAPI-46 PET/CT will be compared to changes on the [18F]FDG PET/CT and the clinical response. The clinical response will be assessed using the patients' medical record.

Tracer-uptake in healthy tissue and benign lesions on [68Ga]Ga-FAPI-46 PET/CT will be evaluated using the same method as described in "Primary Objectives". A similar evaluation of standard [18F]FDG PET/CT will be performed. FAPI-uptake in healthy tissue on [68Ga]Ga-FAPI-46 PET/CT will be compared to the findings on [18F]FDG PET/CT. To verify the [68Ga]Ga-FAPI-46 PET/CT assessment (including evaluation of healthy tissue, malignant lesions and benign lesions), the assessment will be compared to the findings from a composed reference standard. This consist of all available imaging, biopsy results, blood tests, and information on hospitalization and changes in patient management up to 6 months after the [68Ga]Ga-FAPI PET/CT.

Blood samples from the included participants will be analyzed by Nordic Bioscience- Results from this analysis will be correlated to the disease activity evaluated on the [68Ga]Ga-FAPI-46 PET/CT. Results from the serum blood sample analysis will also be correlated with treatment outcome after 6 months of treatment. Treatment outcome will be defined using the RECIST criteria (40). This analysis will be done retrospectively on routine clinical scans ([18F]FDGPET/CT). The updated guideline and definitions of the RECIST criteria will be used.