18F-FDHT

**18F-FDHT** is a radiopharmaceutical used primarily as a positron emission tomography (PET) imaging agent to noninvasively assess androgen receptor (AR) expression in vivo. It is a radiolabeled analog of dihydrotestosterone, labeled with the radioisotope fluorine-18. Upon administration, it binds specifically to androgen receptors, allowing visualization and quantification of AR-positive tissues—most notably in prostate cancer and metastatic breast cancer. The tracer demonstrates high specificity for AR over other steroid hormone receptors and has favorable pharmacokinetics for imaging applications. Its uptake can be competitively inhibited by endogenous or exogenous R.androgens, confirming its mechanism via AR binding[1][2][3][4][5]. Most circulating 18F-FDHT is bound to sex hormone–binding globulin (SHBG), which facilitates its transport into cells[2][6]. Clinical studies have shown that PET imaging with this agent correlates well with immunohistochemical detection of AR expression in tumors[2][3]. It is used both for initial staging and monitoring response to anti-androgen therapies in prostate cancer, as well as being investigated for use in breast cancer and glioblastoma multiforme (GBM)[7][9].

Other names

fluorine F 18 FDHT16β-[18F]-fluoro-5α-dihydrotestosterone