European interlaboratory comparison of serum thyroglobulin measurement.
A European interlaboratory comparison of serum thyroglobulin measurements was performed after an initiative from the European Organization of Research and Therapy of Cancer. Fifty-two laboratories were addressed and 45 of these (83%) participated in the study by measuring serum thyroglobulin and its autoantibody in 5 thyroglobulin containing sera. Thyroglobulin antibodies were added to two of the sera. Two commercial kits were used by a large number of the laboratories (11 and 8, respectively). Each kit showed a reasonably low interlaboratory coefficient of variation at concentrations above 25 micrograms/l, but with discrepancy between the methods. The remaining miscellaneous methods (24) showed a variation above 65% in all samples. In all laboratories the addition of thyroglobulin antibodies resulted in false thyroglobulin measurements with either elevated or depressed levels. It is concluded that a reference calibrator for serum thyroglobulin is strongly needed as the first essential step towards interlaboratory standardization of serum thyroglobulin, thereby opening a possibility for multicentre studies of its value in the post-therapy follow-up of patients with differentiated thyroid carcinoma.
Feldt-Rasmussen
U
U
Department of Medicine E, Frederiksberg Hospital, Copenhagen, Denmark.
Schlumberger
M
M
D002985:Clinical Protocols / Q000592:standards*; D005060:Europe; D006801:Humans; D007753:Laboratories / Q000592:standards*; D012015:Reference Standards; D013954:Thyroglobulin / Q000097:blood*
D013954:Thyroglobulin