Is it safe to just keep an eye on the Tg levels?

[abby51]

After having stopped my Synthroid for 6 weeks because insurance would not pay for Thyrogen, I had my thyroglobulin tested and a PET/CT scan done a few days ago, with the results coming back as 9 for the Tg level and nothing showing on the scans.

Because nothing is showing on the scans I have chosen to watch the Tg level rather than do any type of treatment other than, of course, start Synthroid again. The radiation oncologist gave me an option today of trying radiation again, however, if nothing is seen on any scans I really do not see a point in doing so, especially since it will not be I-131. And even if it were, I think I would still choose to just keep an eye on the Tg levels. The oncologist said I may have a very small remnant of thyroid cancer. The endocrinologist says the last ultrasound I had done showed possible thyroid cancer, but not according to the scans.

The oncologist and endocrinologist say I will just have to be monitored more closely due to having a detectable Tg level even after external beam radiation. I am fine with this, however, I feel fine, am working full time and a full time law student so I see no need to interrupt that for something that cannot even be seen on scans.

Would you recommend that it is okay to just keep an eye on the Tg levels and perhaps get it tested every so often? I am confused, do not really know if I made the right decision, and I did not feel confident that they really knew what the best answer was either.

I have posted a question previously when I first began having problems with the Tg levels.

Thank you.

[abby51]

I have had an ultrasound done on my neck (Oct. 2007) and the radiologist said there are 2 suspicious spots but neither has been biopsied yet.

I am back on Synthroid (125) which in itself is a huge plus, and they added Cytomel (75) this time.

I realize it is most likely not aggressive, small, and not going to cause a lot of problems, however, I also do not want to keep getting tested over and over.

I was very young when I was first diagnosed 14 years ago and I had no problems whatsoever for a very long time.

[Mark Lupo, M.D.]

I thought you had posted previously as I was reading this question....

External beam is extreme, would get at least 2 second/third opinions before considering....

That being said, ultrasound is more sensitive than PET/CT in many cases of persistent cancer in the neck -- find a good thyroid specialist who does his/her own ultrasound and FNA biopsy any area that is suspicious.  

On the other hand....the lack of PET positivity suggests that the tumor is not highly aggressive (but does not prove there is not tumor present!).

If nothing on US, then following Tg levels would be appopriate in most cases like this -- if there is an increase then more investigation would be needed.