Differences between 99mTc-sestamibi and 99mTc-tetrofosmin uptake in thyroid and salivary glands: comparison with 99mTc-pertechnetate in 86 subjects.
Tc-tetrofosmin seems to show a prolonged thyroid retention when compared with Tc-sestamibi; this may explain its poorer performance in the dual-phase parathyroid scintigraphy. In order to verify objectively whether and to what extent Tc-sestamibi and Tc-tetrofosmin uptake and retention differ in the thyroid gland, we performed a head-to-head comparison between the tracers in 86 euthyroid subjects enrolled in five centres. Data were compared with those of Tc-pertechnetate obtained from the same subjects. For comparison purposes, quantitative data from the salivary glands were also obtained. Tc-sestamibi showed a higher early thyroid uptake (2.26+/-0.52 vs. 2.01+/-0.49, respectively; P<0.002) and a lower retention (1.4+/-0.37 vs. 1.65+/-0.58, respectively; P<0.002) when compared with Tc-tetrofosmin. This finding provides an objective basis for the poorer results of Tc-tetrofosmin in dual-phase parathyroid scintigraphy. Delayed Tc-tetrofosmin salivary gland uptake was unexpectedly high and approached the Tc-pertechnetate value (2.29+/-0.56 vs. 2.46+/-0.75, respectively; P =not significant). This finding should be kept in mind in order to avoid interpretation pitfalls in thyroid and parathyroid imaging with Tc-tetrofosmin, as well as in other oncological imaging of the neck region. This study definitely establishes that Tc-tetrofosmin and Tc-sestamibi are not twin but rather sibling tracers.
Giordano
A
A
Departments of Nuclear Medicine, Policlinico Gemelli, Università Cattolica del S Cuore, Rome, Italy. a.giordano@rm.unicatt.it
Meduri
G
G
Marozzi
P
P
Rubini
G
G
Burroni
L
L
Cappagli
M
M
D001692:Biological Transport; D006801:Humans; D006961:Hyperparathyroidism / Q000000981:diagnostic imaging*; D007558:Italy; D009943:Organophosphorus Compounds / Q000493:pharmacokinetics*; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012469:Salivary Glands / Q000000981:diagnostic imaging* / Q000378:metabolism; D013670:Sodium Pertechnetate Tc 99m / Q000493:pharmacokinetics*; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics*; D013961:Thyroid Gland / Q000000981:diagnostic imaging* / Q000378:metabolism; D014018:Tissue Distribution
D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C078700:technetium tc-99m tetrofosmin; D017256:Technetium Tc 99m Sestamibi; D013670:Sodium Pertechnetate Tc 99m