Calcitonin and Carcinoembryonic Antigen (CEA) Doubling Time Calculator

Please note: Due to HIPAA regulations, the information entered into the calculator is not retained by the ATA system. Once you exit the calculator page, any calculated data and results will no longer be available. However, you may enter a non-HIPAA patient identifier and print the calculator results to maintain for your record-keeping purposes.

The monitoring of calcitonin levels play an important role in the follow-up and management of patients with medullary thyroid cancer. Calcitonin doubling times of > 2 years seem to be associated with a better long term prognosis then those < 6 months. The calculator is intended for use by healthcare providers as appropriate medical training and clinical experience is required for interpretation of the results and application to care of individual patients. Providers are referred to the recently published ATA Guidelines on Medullary Thyroid Cancer.

Based on available data, it is recommended to use a minimum of 4 calcitonin values preferably spread over a 2 year period. For a valid result, it is essential that all the calcitonin results have been obtained from the same laboratory and assay.

(One record per line. The two tables should have equal number of records.)
Patient Reference
Date of Test Calcitonin CEA
(mm/dd/yyyy) (must be number) (must be number)

Thyroid Disease Calculators – Disclaimer

The American Thyroid Association has posted these thyroid disease related calculators to provide assistance to practitioners for select practice areas concerning thyroid disease and thyroid cancer. It is recommended that these calculators be used in conjunction with respective ATA guidelines. The calculators and related guidelines are not inclusive of all proper approaches or methods, or exclusive of others. The calculators do not establish a standard of care and specific outcomes with their use are not guaranteed.

Treatment decisions must be made based on the independent judgment of health care providers and each patient’s individual circumstances. The calculator is not intended to take the place of physician judgment in diagnosing and/or treatment of particular patients. The ATA posts calculators based on the evidence available in the literature and the expert opinion of ATA members in the recent timeframe of the development of calculators. Calculators cannot account for individual variation among patients.

Therefore, the American Thyroid Association considers use of these calculations to be voluntary, with the ultimate determination regarding their application to be made by the treating physician and health care professionals with the full consideration of the individual patient’s clinical history and physical status.