Tg (not to be confused with thyroid binding globulin,
Thyroglobulin is a sensitive marker of recurrent thyroid cancer
following total thyroidectomy.
It is normally present in low concentrations in serum and
increases in a range of thyroid diseases, including thyroid cancer,
and is too non-specific to be of value in diagnosis.
Endogenous antibodies to thyroglobulin may invalidate the assay
for serum thyroglobulin. Please contact the laboratory if
thyroglobulin results do not correlate with clinical suspicion of
recurrence, so that the sample can be checked for interfering
Request on ICE
Analysed by referral laboratory if specific criteria met.
Monitoring for recurrent thyroid cancer following total
Serum in plain red topped tube
SST samples are NOT suitable
No specific collection conditions.
Sent to the Queen Elizabeth Hospital Birmingham, B15 2WB
Causes for Rejection
Unlabelled or inadequately labelled sample
Incorrect specimen tube
Request doe not meet specific criteria
Less than 5 µg/L.
After total thyroidectomy, thyroglobulin should no longer be
detectable and measurable or rising concentrations imply the
presence of thyroid tissue, presumably a recurrence of the cancer.
Detection of recurrence may be made more sensitive by withdrawing
replacement thyroxine therapy which causes TSH to rise.
Elevations may occur in untreated toxic nodular goitre, Grave's
disease, acute and chronic thyroiditis.