Serum thyroglobulin concentrations and (131)I whole-body scan results in patients with differentiated thyroid carcinoma after administration of recombinant human thyroid-stimulating hormone.
The use of recombinant human thyroid-stimulating hormone (rhTSH) has recently become available as an alternative diagnostic tool to assess the persistence and recurrence of differentiated thyroid carcinoma (DTC) in patients on thyroid hormone-suppressive therapy (THST) after near-total or total thyroidectomy and ablative doses of (131)I. We report the results of rhTSH administration in patients who were monitored for DTC.


METHODS
Thirty-three adult DTC patients (13 men, 20 women; mean age +/- SE, 45.6 +/- 2.31 y; age range, 21-65 y) underwent diagnostic follow-up after rhTSH administration at a dose of 0.9 mg once a day for 2 d. Whole-body scanning and serum thyroglobulin (Tg) measurement were performed after rhTSH administration. Patients were divided into 2 groups depending on serum Tg concentrations on THST: 29 patients had Tg concentrations of <2 ng/mL (group A) and 4 patients had Tg values of >2 ng/mL (group B).


RESULTS
In group A, Tg values remained at <2 ng/mL in 25 patients and increased from 1.1 +/- 0.14 ng/mL to 22.0 +/- 5.75 ng/mL (mean +/- SE) in 4 patients after rhTSH administration. Whole-body scanning did not reveal any uptake of (131)I in the 25 patients without an increase in Tg, whereas (131)I uptake was evident in 2 of the 4 patients with a rise in Tg. In group B, Tg values increased in all 4 patients from 17.3 +/- 6.35 ng/mL to 55.3 +/- 12.75 ng/mL, and (131)I uptake was evident in 3 of the 4 patients. No major adverse effects were reported after rhTSH administration.


CONCLUSIONS
Our results show that the measurement of serum Tg concentrations after rhTSH has a higher diagnostic value than whole-body scanning in detecting the persistence of thyroid tissue. Therefore, rhTSH should be administered in TSH-suppressed patients with basal serum Tg concentrations of <2 ng/mL because the increment in serum Tg concentrations may reveal the persistence of thyroid tissue in these patients.
David
A
A
Section of Endocrinology, Department of Biomedical Sciences and Advanced Therapies, University of Ferrara, via Savonarola 9, 44100 Ferrara, Italy.
Blotta
A
A
Bondanelli
M
M
Rossi
R
R
Roti
E
E
Braverman
L E
LE
Busutti
L
L
degli Uberti
E C
EC
D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000556:secondary; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual; D011877:Radionuclide Imaging; D011994:Recombinant Proteins; D013954:Thyroglobulin / Q000097:blood*; D013964:Thyroid Neoplasms / Q000097:blood / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000188:drug therapy; D013972:Thyrotropin
D007457:Iodine Radioisotopes; D011994:Recombinant Proteins; D013972:Thyrotropin; D013954:Thyroglobulin