[18F]fluoroestradiol radiation dosimetry in human PET studies.
[18F]16alpha-fluoroestradiol (FES) is a PET imaging agent useful for the study of estrogen receptors in breast cancer. We estimated the radiation dosimetry for this tracer using data obtained in patient studies.


METHODS
Time-dependent tissue concentrations of radioactivity were determined from blood samples and PET images in 49 patients (52 studies) after intravenous injection of FES. Radiation absorbed doses were calculated using the procedures of the MIRD committee, taking into account the variation in dose based on the distribution of activities observed in the individual patients. Effective dose equivalent was calculated using International Commission on Radiological Protection Publication 60 weights for the standard woman.


RESULTS
The effective dose equivalent was 0.022 mSv/MBq (80 mrem/mCi). The organ that received the highest dose was the liver (0.13 mGy/MBq [470 mrad/mCi]), followed by the gallbladder (0.10 mGy/MBq [380 mrad/mCi]) and the urinary bladder (0.05 mGy/MBq [190 mrad/mCi]).


CONCLUSIONS
The organ doses are comparable to those associated with other commonly performed nuclear medicine tests. FES is a useful estrogen receptor-imaging agent, and the potential radiation risks associated with this study are well within accepted limits.
Mankoff
D A
DA
Departments of Radiology and Medical Oncology, University of Washington School of Medicine, Seattle, Washington 98195, USA.
Peterson
L M
LM
Tewson
T J
TJ
Link
J M
JM
Gralow
J R
JR
Graham
M M
MM
Krohn
K A
KA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism; D004958:Estradiol / Q000031:analogs & derivatives*; D005260:Female; D005462:Fluorine Radioisotopes; D006801:Humans; D008875:Middle Aged; D011829:Radiation Dosage; D011874:Radiometry; D011960:Receptors, Estrogen / Q000032:analysis; D014018:Tissue Distribution; D014055:Tomography, Emission-Computed
D005462:Fluorine Radioisotopes; D011960:Receptors, Estrogen; D004958:Estradiol; C043436:16-fluoroestradiol