Figure 2.

Quantitative imaging of the androgen receptor. [¹⁸F]-FDHT, which annotates the AR, the central molecular driver of prostate cancer development and progression, is an effective imaging tool to evaluate pharmacodynamic features of candidate therapies. MDV3100 treatment, a second-generation orally bioavailable anti-androgen, was tested in men with castrate-resistant prostate cancer. (A) Chemical structure of positron-emitting ¹⁸F-FDHT and testosterone. (B) MDV3100 serum concentration by dose level. (C) Representative baseline and treatment scans showing marked decrease in radio-androgen uptake in skeletal metastases. Reproduced from Scher et al. (16) (D) Change in standardized uptake value of [¹⁸F]-FDHT PET for men at baseline compared to 4 weeks of treatment.