Diagnosis of Metastatic Tumors on 68Ga-FAPI PET-CT and Radioligand Therapy With 177Lu-EB-FAPI

FAP is a fibroblast activation protein and overexpressed in many tumor tissues. This study is intended to conduct preliminary clinical transformation and internal irradiation dosimetry research on 177Lu-EB-FAPI--a new 177Lu therapeutic drug modified by Evans Blue (EB) for the first time in the world.

Fibroblast activation protein (FAP) is a serine peptidase on the surface of tumor associated fibroblasts. It belongs to type II transmembrane glycoprotein. It is rich and characteristic expressed in tumor associated fibroblasts. It has special biological characteristics and stable genome. FAP is expressed at a high level in mesenchymal cells during the embryonic period and is inhibited shortly after birth. It is usually not expressed or expressed at a low level in the resting tissues of normal adults, but it is highly expressed in diseases related to tissue repair and matrix reconstruction, such as wound healing, inflammatory response, fibrosis and cancer It plays an important role in metastasis and immunosuppression.Currently, 68Ga labeled FAPI (68Ga-FAPI) has been successfully applied to a variety of tumor PET/CT imaging, including lung cancer, breast cancer, and gastrointestinal tract tumors.By modifying FAPI with Evans blue (EB) to form a new EB-FAPI, endogenous albumin can be used as a reversible carrier to prolong the retention time of drugs in the blood, thus increasing the targeted aggregation and retention of 177Lu-EB-FAPI in tumor cells, and effectively killing a variety of transplanted tumors with positive FAP expression.we'll try to assess the safety and therapeutic response to 177Lu-EB-FAPI in patients with metastatic tumors in human.

All patients diagnosed with metastatic tumors underwent 68Ga-FAPI PET/CT scan. If the PET/CT showed high FAPI expression in tumor lesions of some patients, they would intravenously injected with the dose about 1.11GBq (30 mCi) of 177Lu-EB-FAPI for therapy.

Patients with positive results were screened with 68Ga-FAPI PET / CT, and 1.11GBq(30mci) 177Lu-EB-FAPI was injected intravenously for therapy after contraindications were excluded and informed consent was signed.

the therapeutic response assessed by 68Ga-FAPI PET/CT to 177Lu-EB-FAPI in patients with metastatic tumors

Sensitivity and Specificity of 68Ga-FAPI PET/CT for metastatic tumors in comparison with 18F-FDG PET/CT

Inclusion Criteria: confirmed treated or untreated metastatic tumors patients; 68Ga-FAPI PET/CT and 18F-FDG PET/CT within two weeks; signed written consent. Exclusion Criteria: pregnancy; breastfeeding; any medical condition that in the opinion of the investigator may significantly interfere with study compliance

Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College