Assays / Hormones / Thyroglobulin (plasma, serum)

Clinical Use
Evaluation and management of patients treated for thyroid cancer with surgery and radioiodine, and receiving thyroid hormone therapy.
Measurement of thyroglobulin is of no value in the initial diagnosis of thyroid cancer. After ablative surgery, thyroglobulin levels do not discriminate between the presence of normal thyroid tissue and tumour unless thyroid hormone replacement is given. Serial measurements in such patients aid in monitoring for possible recurrence. All samples are tested for antibody interference and less than 4% are now affected in the new assay, introduced in 1994.

Patient Preparation
None. Take blood (5 mL) into a syringe or red topped vacutainer.

Sample Preparation
Transfer the blood to a plain tube. Allow to clot at room temperature, avoiding haemolysis which, with lipaemia, can produce spurious results. Send serum (2 mL) to the SAS laboratory by first class post.

Reference Range
Please contact the SAS laboratory.
Provided the patient receives adequate thyroxine, detectable thyroglobulin indicates the presence of tumour tissue.

Centres offering this assay
Cardiff, Newcastle, Birmingham.

Back to Alphabetical List of Assays Available