4-hydroxy-n-desmethyltamoxifen and 16-fluoroestradiol

Z-endoxifen is the most potent of the metabolites of tamoxifen, and has the potential to be more effective than tamoxifen because it bypasses potential drug resistance mechanisms attributable to patient variability in the expression of the hepatic microsomal enzyme CYP2D6.. Fifteen patients were recruited from a parent therapeutic trial of Z-endoxifen and underwent imaging with. Statistically significant changes (p = 0.0078) in standard uptake value (SUV)-Max were observed between the baseline and follow-up scans as early as 1 day post drug administration.. F-FES PET imaging could serve as a pharmacodynamic biomarker for patients treated with ER-directed therapy.

Topics: Adult; Aged; Breast Neoplasms; Breast Neoplasms, Male; Estradiol; Estrogen Antagonists; Female; Genital Neoplasms, Female; Humans; Male; Middle Aged; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Receptors, Estrogen; Tamoxifen