This is an evolving area in the decision making for RAI. The tumor was 1.5cm by your description with negative margins, no lymph nodes and no other foci of cancer. Would usually not need RAI for this independent of the Tg.
If there is debate on the need for RAI, then Tg levels are sometimes used to determine need and dose of RAI. <5 (on thyroid meds) or <10 (off meds, "stimulated") are levels that may steer towards no RAI in otherwise borderline cases. It really depends on each unique individual situation.
That being said, the other issue is RAI dose -- for low risk cancers (like yours) 30mCi works as well as 100mCi.
Should (lab) tg be used to decide if I 131 ablation is done after thyroidectomy? Patho came back Right lobe papillary thyroid carcinoma, predominantly follicular 1.5x1.5x1.2 cm, that grossly abuts both the anterior and posterior aspects. Left lobe multinodular goiter dominant colloid with calcification not dx for carcinoma. The surgeon says I need it, and I can not think that I have gone this far (total thyroidectomy) and then not do the ablation based on a lab test. I have appointment with oncology June 2nd. I had an appointment May 7th with doctor who ordered labs, TSH, T3, T4, tg, and tgAb, when he called yesterday he said somehow the tg did not get done he is not sure why but never the less no results. So just how important is this test in deciding ablation or no ablation?
Thank you for your response. I had sonogram before uptake, I will not give the entire report but I have several dense nodules both right and left lobe. The left having the larger ones that was reason for uptake. Conclusion on uptake at least one mass 5cm thought to be cold ,supporting dx of thyroid malignancy. Because of the size and the fact there are multiple large nodules the decision to forgo the FNA was made. I thank you so much for letting me know that my labs are not deciding factor .
I would like your opinion on one other matter if you please. Do you think it best to stay for 23 hr. OBS. This is going to be outpatient and I am concerned about length of time in recovery. Main concern Is parathyroid damage or dysfunction and drop in calcium levels.
Labs generally do not predict benign vs cancer. Would do ultrasound to confirm presence of a nodule then likely have FNA biopsy as well as see a thyroid specialist.