{"id":"thyroglobulin","name":"Thyroglobulin (Tg)","shortName":"Thyroglobulin","aliases":["Thyroglobulin","Thyroglobulin, Tumor Marker","Thyroglobulin by LC/MS/MS","Thyroglobulin, Serum","Thyroglobulin, Quantitative","Thyroglobulin Level","Tiroglobulina","Thyroglobulin tumour marker","Thyroglobulin, Tumor Marker, Serum","Thyroglobulin, Mass Spectrometry","Thyroglobulin by Immunoassay"],"abbreviations":["Tg"],"loinc":[{"code":"3013-0","primary":true},{"code":"14918-7","primary":false}],"specimen":"serum","units":[{"ucum":"ng/mL","display":"ng/mL"},{"ucum":"ug/L","display":"µg/L"}],"referenceRanges":[{"population":"Adults","low":0,"high":33,"unit":"ng/mL","unitDisplay":"ng/mL","note":"Mayo Clinic Laboratories' limit (33 ng/mL or less, immunoenzymatic assay) for all ages, as listed on its interference-evaluation profile page. Limits differ a lot by assay. The manufacturer interval for the Roche Elecsys Tg II assay, as quoted in a 2026 laboratory study, is 3.5 to 77 µg/L (the same numbers as ng/mL). A study of healthy, non-smoking adults with a normal thyroid ultrasound, negative thyroid antibodies and TSH 0.5 to 2.0 mIU/L (mean age 34.7 years) on the Beckman Coulter Access assay found 1.40 to 29.2 ng/mL for men and 1.50 to 38.5 ng/mL for women, with higher levels in women. Levels can also be higher where iodine intake is low. These intervals describe people who still have a thyroid. After thyroid removal and radioactive iodine for thyroid cancer, the goal is a very low or undetectable level (MedlinePlus), and the follow-up targets that care teams use are different (ATA 2015, as summarized in two open-access studies; see technical notes). Needle-biopsy wash fluid has its own cutoff (Mayo lymph node: 1.0 ng/mL or less). Use the interval printed on your own report.","sources":[{"title":"Interference Evaluation Heterophile, Thyroglobulin Tumor Marker, Serum (test IETG)","url":"https://www.testcatalog.org/show/IETG","publisher":"Mayo Clinic Laboratories, via the Mayo Clinic Laboratories extended catalog"},{"title":"Serum thyroglobulin reference values according to NACB criteria in healthy subjects with normal thyroid ultrasound","url":"https://pubmed.ncbi.nlm.nih.gov/22628333/","publisher":"Clinical Chemistry and Laboratory Medicine","year":2012},{"title":"Use of thyroglobulin as a tumour marker","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC5329716/","publisher":"World Journal of Biological Chemistry","year":2017},{"title":"Critical appraisal of the influence of antithyroglobulin on the measurement of thyroglobulin and thyroglobulin recovery","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC13519048/","publisher":"Journal of the Endocrine Society","year":2026},{"title":"Thyroglobulin, Tumor Marker, Fine-Needle Aspiration Biopsy Needle Wash (test TFNAB)","url":"https://www.testcatalog.org/show/TFNAB","publisher":"Mayo Clinic Laboratories, via the Mayo Clinic Laboratories extended catalog"},{"title":"Thyroglobulin Test","url":"https://medlineplus.gov/lab-tests/thyroglobulin/","publisher":"MedlinePlus (NIH National Library of Medicine)"},{"title":"2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer","url":"https://doi.org/10.1089/thy.2015.0020","publisher":"Thyroid (American Thyroid Association)","year":2016},{"title":"Comparison of Ultrasensitive and Highly Sensitive Assay to Predict Stimulated Thyroglobulin Levels Using Unstimulated Levels in Differentiated Thyroid Cancer Patients","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC12602004/","publisher":"Endocrinology and Metabolism","year":2025},{"title":"Disease status stratification individualizes radioiodine therapy for differentiated thyroid cancer: a prospective, multicenter, real-world study","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC13245083/","publisher":"BMC Cancer","year":2026}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"A protein made only by thyroid cells. It is mainly used after thyroid cancer treatment as a tumor marker, and it is not a test for diagnosing cancer.","url":"https://bloodtesttracker.com/markers/thyroglobulin","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}