Cancer Survivors Network

My understanding is that thyroglobulin of greater than zero indicates that there remain some thyroid cells, though Tg in itself cannot indicate the presence of cancerous thyroid cells - simply thyroid cell existence. It is also true that I-131 works for months and I think they say sometimes it can crest before going down. A key with Tg is the TREND. You want to see a downward trend. If it goes up, more tests need to be done to determine what is going on (ie, new nodule growth, mets, etc). You have to stay on top of it, as I am sure you and your husband are aware.

Thyca.org has some really useful information on the I-131 process and also helpful explanations of various labs and tests, including Tg. (http://www.thyca.org/thyroglobulin.htm). I found it to be a great site for understanding thyroid cancer a little better.

Make sure to always get copies of all labs and tests so you can be your own advocate. Always ask the docs any questions you may have. Very best to you all.
eileen

9 months after RAI my thyroglobulin QN is <0.10 ng/mL <-- considered undetectable
prior to RAI my thyroglobulin QN was 2.41 ng/ml

it also matters what your thyroidglobulin antibodies is at (mine is alos <20IU/mL)<--undetectable

so for me if eithor of these numbers becomes detectable in the future it means I have a likely reocourance.

again it is all about the amount you have and how it changes if your husbands levels have not changed then the amount of thyroid tisue in the body has not changed if it goes up then it is likely there is a re-occurance.

what was your daughters thyroglobulin level prior to RAI and 2-3 months after ... is the number going down or stable.

again the fact that there is a thyroglobulin QN level means there is thyroid tissue left dose not mean cancer but if it is increasing then it probably is cancer.

again you can learn alot about reading lab results as have I but you then need to take all the info you have learned about the labs and point out your concerns to your/there doctor they are the only one who can tell you whats up.

good luck keep us informed and ask as many questions as you can think of

Craig

I had a thyroidectomy in Feb. 2010 and the I-131 treatment. Over the course of the last year, my thyroglobulin levels have come down but are not low enough. Currently is 2.1 and Dr. says it needs to go down to at least 0.2. I also have antibodies which throw off these numbers -- Dr. says 2.1 is not accurate and is, more than likely, higher. It is now time to do the prep to the body scan to see if there is remaining thyroid tissue. This tissue may still be producing hormones and throwing off the numbers or it could be cancerous. The oncologist is pretty sure I will need the I-131 again. Also, the endocrinologist has been sending my last three blood labs to UCLA for testing because of the antibodies--I guess their results are more accurate. It did take a year for these numbers to come down and I believe it will continue to drop. Maybe your daughter's numbers will drop also in the next few months.

My dilemma, right now, is trying to decide whether I want to go through the 6 week withdrawal of synthroid for the prep or get the thyrogen injections so I don't have to stop the synthroid. I was told the thyrogen injections help to clear out the radiation faster from the organs and the bone marrow.

I had a thyroidectomy in Feb. 2010 and the I-131 treatment. Over the course of the last year, my thyroglobulin levels have come down but are not low enough. Currently is 2.1 and Dr. says it needs to go down to at least 0.2. I also have antibodies which throw off these numbers -- Dr. says 2.1 is not accurate and is, more than likely, higher. It is now time to do the prep to the body scan to see if there is remaining thyroid tissue. This tissue may still be producing hormones and throwing off the numbers or it could be cancerous. The oncologist is pretty sure I will need the I-131 again. Also, the endocrinologist has been sending my last three blood labs to UCLA for testing because of the antibodies--I guess their results are more accurate. It did take a year for these numbers to come down and I believe it will continue to drop. Maybe your daughter's numbers will drop also in the next few months.

My dilemma, right now, is trying to decide whether I want to go through the 6 week withdrawal of synthroid for the prep or get the thyrogen injections so I don't have to stop the synthroid. I was told the thyrogen injections help to clear out the radiation faster from the organs and the bone marrow.