title: A phase 2 study of 16α-[18F]-fluoro-17β-estradiol positron emission tomography (FES-PET) as a marker of hormone sensitivity in metastatic breast cancer (MBC).
abstract: OBJECTIVE
  16α-[(18)F]-fluoro-17β-estradiol positron emission tomography (FES-PET) quantifies estrogen receptor (ER) expression in tumors and may provide diagnostic benefit.
  
  
  METHODS
  Women with newly diagnosed metastatic breast cancer (MBC) from an ER-positive primary tumor were imaged before starting endocrine therapy. FES uptake was evaluated qualitatively and quantitatively, and associated with response and with ER expression.
  
  
  RESULTS
  Nineteen patients underwent FES imaging. Fifteen had a biopsy of a metastasis and 15 were evaluable for response. Five patients had quantitatively low FES uptake, six had at least one site of qualitatively FES-negative disease. All patients with an ER-negative biopsy had both low uptake and at least one site of FES-negative disease. Of response-evaluable patients, 2/2 with low FES standard uptake value tumors had progressive disease within 6 months, as did 2/3 with qualitatively FES-negative tumors.
  
  
  CONCLUSIONS
  Low/absent FES uptake correlates with lack of ER expression. FES-positron emission tomography can help identify patients with endocrine resistant disease and safely measures ER in MBC.
authors.affiliation: Radiology/Nuclear Medicine, University of Washington Medical Center-Seattle Cancer Care Alliance, Seattle, WA, USA, lanell@uw.edu.
authors.forename: Lanell M
authors.initials: LM
authors.lastname: Peterson
authors.forename: Brenda F
authors.initials: BF
authors.lastname: Kurland
authors.forename: Erin K
authors.initials: EK
authors.lastname: Schubert
authors.forename: Jeanne M
authors.initials: JM
authors.lastname: Link
authors.forename: V K
authors.initials: VK
authors.lastname: Gadi
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Specht
authors.forename: Janet F
authors.initials: JF
authors.lastname: Eary
authors.forename: Peggy
authors.initials: P
authors.lastname: Porter
authors.forename: Lalitha K
authors.initials: LK
authors.lastname: Shankar
authors.forename: David A
authors.initials: DA
authors.lastname: Mankoff
authors.forename: Hannah M
authors.initials: HM
authors.lastname: Linden
mesh_terms: D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D004958:Estradiol; D005260:Female; D005462:Fluorine Radioisotopes; D006801:Humans; D009362:Neoplasm Metastasis / Q000473:pathology*; D049268:Positron-Emission Tomography / Q000379:methods*
chemical_list: D005462:Fluorine Radioisotopes; D004958:Estradiol