Fig. 7.
A 79-year-old female with metastasized breast and colon cancer underwent within 1.5 years eight 68Ga-FAPI-PET/CT with three different derivates (FAPI-02, FAPI-04, FAPI-46). During that time interval, mainly palbociclib and four cycles of Y-90-FAPI-radioligand therapy were applied. The progression markers CA 15-3 and CA 19-9 were monitored showing a temporary stable and even regredient disease, which is in concordance with FAPI uptake presented in the PET/CT. However, after a while, the patient possibly developed a resistance against palbociclib or radioligand therapy, presenting with possible progressive disease leading to a change of therapy