title: Factors influencing the uptake of 99mTc-sestamibi in breast tissue on molecular breast imaging.
abstract: The purpose of this study was to evaluate the impact of changes to a patient's prandial status, metabolic status (rest vs. exercise), and peripheral blood flow (via caffeine or warming) on the uptake of (99m)Tc-sestamibi in breast tissue.
  
  
  METHODS
  A total of 154 subjects participated in 1 of 4 study groups that evaluated the effects of 4 types of intervention on the uptake of (99m)Tc-sestamibi in breast tissue (effect of fasting, light exercise, caffeine, and peripheral warming). Molecular breast imaging was performed before and after each intervention. Count density was assessed in counts/cm(2)/MBq from the mediolateral oblique view in all studies.
  
  
  RESULTS
  Uptake of (99m)Tc-sestamibi in breast tissue increased by approximately 25% from 6.6 counts/cm(2)/MBq in the fed state to 8.3 counts/cm(2)/MBq with fasting. Peripheral warming also resulted in an approximately 20% increase in count density from 9.1 to 10.9 counts/cm(2)/MBq. Conversely, exercise caused a 35% drop in count density relative to the resting state. Uptake did not seem to be influenced by caffeine and did not correlate with a patient's height, weight, or breast thickness. There was only a weak correlation between breast activity and body surface area.
  
  
  CONCLUSIONS
  The combined effects of fasting and warming resulted in an approximately 50% increased uptake of (99m)Tc-sestamibi in breast tissue relative to that observed in a reference group to whom no preparatory instructions had been given. Optimal patient preparation before administration of (99m)Tc-sestamibi should permit a corresponding reduction in either acquisition time or required dose of (99m)Tc-sestamibi.
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota mkoconnor@mayo.edu.
authors.forename: Michael K
authors.initials: MK
authors.lastname: O'Connor
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Carrie B
authors.initials: CB
authors.lastname: Hruska
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Thuy D
authors.initials: TD
authors.lastname: Tran
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Tiffinee
authors.initials: T
authors.lastname: Swanson
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Amy Lynn
authors.initials: AL
authors.lastname: Conners
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Katie
authors.initials: K
authors.lastname: Jones
authors.affiliation: Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota.
authors.forename: Deborah J
authors.initials: DJ
authors.lastname: Rhodes
mesh_terms: D000328:Adult; D001692:Biological Transport / Q000187:drug effects; D001775:Blood Circulation / Q000187:drug effects; D001940:Breast / Q000098:blood supply / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D002110:Caffeine / Q000494:pharmacology; D015444:Exercise; D005215:Fasting; D005260:Female; D006801:Humans; D057054:Molecular Imaging / Q000379:methods*; D012146:Rest; D017256:Technetium Tc 99m Sestamibi / Q000378:metabolism*
chemical_list: D002110:Caffeine; D017256:Technetium Tc 99m Sestamibi
keywords: 99mTc-sestamibi; breast; exercise; fasting