Value of protein-bound radioactive iodine measurements in the management of differentiated thyroid cancer treated with (131)I.
Measurement of the protein-bound radioactive iodine level (PBI(131)) in the plasma of patients following (131)I-iodide administration for thyroid cancer has been re-examined in a retrospective study of 171 patient episodes. It is shown that whereas the previously used threshold value for the measurement at 6 days does not correlate well with the 3-day whole body scan, there is good agreement between the scan and the temporal changes in PBI(131) from 1-6 days: an increasing PBI(131) correlates with a positive scan, and a decreasing PBI(131) with a negative scan. The area under the curve (AUC) for the PBI(131)-time curve is related to the absorbed dose for the tumour. For a small group of 11 patients, dosimetry estimates were made from serial scans, quantified with phantoms; these absorbed doses correlated with the AUC and the 6-day PBI(131). Therefore, it is suggested that these parameters may be useful in predicting absorbed radiation dose in these patients.
Hammersley
P A
PA
Department of Nuclear Medicine, Royal Marsden Hospital NHS Trust, Downs Road, Sutton, Surrey SM2 5PT, UK.
Al-Saadi
A
A
Chittenden
S
S
Flux
G D
GD
McCready
V R
VR
Harmer
C L
CL
D000042:Absorption; D000837:Anion Exchange Resins; D019540:Area Under Curve; D015902:Gamma Cameras; D006801:Humans; D007457:Iodine Radioisotopes / Q000097:blood* / Q000493:pharmacokinetics / Q000627:therapeutic use; D019047:Phantoms, Imaging; D011485:Protein Binding; D011874:Radiometry; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000097:blood / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D013975:Thyroxine-Binding Proteins / Q000378:metabolism; D014055:Tomography, Emission-Computed
D000837:Anion Exchange Resins; D007457:Iodine Radioisotopes; D013975:Thyroxine-Binding Proteins