This article is from the Journal of the American Medical Association and is an excellent overview of post-op thyroglobulin monitoring
JAMA Patient Page
March 26, 2019Thyroglobulin for Monitoring for Thyroid Cancer Recurrence
Alan N. Peiris, MD, PhD, FRCP(Lond)1,2; Dillon Medlock, BS2; Meredith Gavin, BS2
Author Affiliations Article Information
JAMA. 2019;321(12):1228. doi:10.1001/jama.2019.0803
Some thyroid cancers can come back after removal, so monitoring for recurrence is important.
The thyroid gland is located in the lower front part of the neck above the breastbone and regulates metabolism through production of thyroid hormones (T3 and T4). Thyroid cancer is a malignant tumor of the thyroid gland. Papillary and follicular thyroid cancers are the most common types, and are known as differentiated thyroid cancers because they process iodine similarly to normal thyroid tissue. Surgery is the initial treatment for papillary or follicular thyroid cancers.
After initial treatment, long-term monitoring is needed to check for recurrence of the cancer. This is done by repeat ultrasound examinations of the neck, radioactive scanning, and measuring thyroglobulin levels in the blood.
Thyroglobulin is a protein made by the follicular cells of the thyroid gland. It is used by the thyroid gland to produce T3 and T4. The normal value for thyroglobulin is 3 to 40 nanograms per milliliter in a healthy patient. If a patient’s thyroglobulin level is found to be increasing after all of the thyroid gland has been removed, the patient may have a recurrence of a differentiated thyroid cancer. Very high levels of thyroglobulin may suggest metastatic or recurrent disease. About one-fourth of patients who have thyroid cancer have antibodies to thyroglobulin. Antibodies should be checked along with thyroglobulin because if they are present, they could interfere with measurement of thyroglobulin. Thyroglobulin levels after a lobectomy (removal of half of the thyroid gland) should correlate with the size of the thyroid gland remaining after surgery. Falsely high values of thyroglobulin can occur after a partial thyroidectomy because the remaining thyroid gland can increase in size. Following thyroid gland removal, radioactive iodine ablation (destruction) of residual thyroid tissue maybe done to reduce chance of recurrence and to make monitoring of thyroglobulin more reliable.
How Is Thyroglobulin Measured?
Thyroglobulin is measured using enzyme-linked immunosorbent assay (ELISA). The accuracy of the test depends on how strong the binding is between thyroglobulin and the antibody used. If a thyroglobulin value seems abnormal, the ELISA test should be done again to ensure the results are accurate. There are other tests for thyroglobulin; the results of tests depend on which type of test was done. When comparing test results, it is important that tests were the same type and done in the same laboratory.
Thyroglobulin levels should be measured every 3 to 6 months for 2 years after thyroidectomy and every 6 to 12 months after that. Depending on an individual patient’s circumstances, the amount of testing may differ. If thyroglobulin levels are increasing, the cancer may have returned. When a thyroglobulin level is increased, testing should be done more frequently. When levels are decreasing, the cancer is probably receding. When there is a cancer recurrence, thyroglobulin levels can be suppressed at the same time that levels of thyroglobulin antibodies increase.
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Conflict of Interest Disclosures: None reported.
Sources: American Thyroid Association
Holsinger FC, Ramaswamy U, Cabanillas ME, et al. Measuring the extent of total thyroidectomy for differentiated thyroid carcinoma using radioactive iodine imaging. JAMA Otolaryngol Head Neck Surg. 2014;140(5):410-415. doi:10.1001/jamaoto.2014.264
This week I was down in London to attend the Royal Marsden update in the management of Thyroid Cancer. This was hosted by Dr Kate Newbold and was excellent.
There were talks on the role of biomarkers in the diagnosis and potential prognosis of thyroid cancer and discussions about the role of as well as the management of potential side effects of tyrosine kinase inhibitors. These new drugs block the growth of certain cancer cells and in thyroid cancer that is no longer responding to radio-iodine treatment they have become a game-changer.
The day ended with a panel discussion on the management of difficult cases. All in all an excellent course and now back to put it all into practice.
This podcast is from a while ago and summarise a systematic review that I undertook for the Cochrane Collaboration looking at the benefit of masking devices for tinnitus. It is, hopefully, a useful introduction into what tinnitus is and how it can be treated. The bottom line is that masking devices are probably better than no treatment at all and there is no harm associated with their use.
Link to the full study here:
I am now delighted to be working with McCollum Consultants - one of the UK's leading team of medico-legal experts. Check out my bio here.
This week, I have been over in Washington DC at the ATA. It has been a great opportunity to network and learn from leaders in the field as well as to find out about cutting edge advances in thyroid cancer and thyroid disease.
One of the things I am most excited about is molecular testing. Currently in the UK, if you come and see me in my neck lump clinic you will have an ultrasound scan. Many of these will show benign nodules with no further action needed and I can often reassure and discharge you on the same day. Many people, however, will have a thyroid nodule that does not appear normal. A small number of these will look like an obvious cancer and you will go ahead and have surgery but some will just be in the grey area and so a needle test (FNA) is done. This is reported on a five point scale Thy 1-5 and again some people will be discharged with a diagnosis of a benign nodule whereas others will go straight to surgery. The majority of patients, however, will have a diagnosis of Thy 3a or Thy 3f which means that some cells have been seen that do not look normal but nor is there concrete evidence of a cancer. The risk of a cancer for these groups is 5-15% and 30% respectively and, although this is still low, we usually recommend a hemithyroidectomy to make a diagnosis. This does mean, however, that up to 85% of our patients that we operate on will turn out to have benign disease and, with hindsight, did not need surgery.
This is where molecular testing comes in. After the needle test, as well as looking at the cells under the microscope some is analysed to look at its RNA and DNA and identify genes that are known to cause cancer. The main 4, in increasing order of aggressiveness are:
If any of these come back then we would go ahead and recommend surgery. The company that I have been talking with is called Thyroseq and they produced reports like the ones below.
The really amazing thing is that with the specificity and sensitivity of the tests - if a test comes back as negative then there is a 97% chance of this being a true negative and so surgery would probably not be recommended as long as there were no other patient risk factor. If the test comes back as positive then we would go ahead with surgery. Following results from a multicentre trial - it seems as if up to 60% of patients with indeterminate nodules will have a negative report and can therefore avoid surgery with the consequent risks and anxiety associated with it.
This has been available in the US for some time now and I am excited to see it in the UK, it is truly the future of diagnosis for thyroid nodular disease.
Today was a full day of audit and clinical effectiveness (ACE) at Wythenshawe Hospital. As well as great talks on the Coronial process, mental capacity and a talk to the head and neck unit from our director of operations we had the opportunity to roll out this initiative that has come from East Lancs NHS Trust. It is called 10,000ft (3048m!) and uses a simple concept to allow all team members to highlight problems, concerns and times when extra concentration is needed - particularly in the operating theatre #10000ft #MFT #patientsafety
This weekend I was lucky enough to be invited to crew a 40ft yacht - sailing around the Solent in the 2018 NHS regatta. We had a crew of 8 - consultant colleagues from Wythenshawe Hospital. Over the 2 days of racing, our best positions were 1st, 1st, 2nd and 5th and we won the regatta overall. A proud achievement and a great introduction to sailing.
This year it was a trip down to the NEC in Birmingham for an excellent conference. There was a fascinating talk by barrister Nick Deal on the CPR Part 35 rules and an interesting and interactive session with Scot Darling on a variety of medico-legal scenarios
I had an enjoyable morning discussing interview skills and techniques with some of our really keen and enthusiastic North West and Mersey ENT trainees. As promised - the handout is below to download - good luck for the interviews next year - I'm sure you'll all do really well!
Last week I attended an excellent seminar in London organised by Premex+ The seminar was a great introduction to the basic of medical negligence law and the requirements needed to be an Expert Witness in that field. Thanks to the team for organising it.