Question
I’d like to tap into the expertise of this forum (Thyroid Manager) regarding an unusual situation in a pediatric patient. Patient was a non-adherent young, obese 14 yo teen with an original diagnosis of congenital hypothyroidism secondary to dyshormonogenesis. He’d been lost to follow-up for more than a year. Upon return, he presented with an asymptomatic 2.5 cm nodule. Biopsy results suggested follicular adenoma with pre-malignant features (I don’t recall at this time.). Subsequent total thyroidectomy led to the finding of a 6mm papillary carcinoma on the contralateral side of the original lesion. He was ablated with I131 following surgery. Thyroglobulin levels were unmeasurably low when his TSH was 130 uU/mL about 2 months following the ablation. He has since become adherent to treatment with Synthroid and TSH has been maintained around 0.02 uU/mL. Microcarcinoma is a well-described phenomenon in adults, but not in children. Is this a patient (now 15 yo) who will need to have regular scans to look for metastases? Does he need to be this suppressed? Any input will be greatly appreciated.
Thanks,
Vered Lewy, M.D.
Response
Your case raises many issues. I suppose that in the presence of dys-hormonogenesis, and "non-adherence", that his tumor could be related to excessive TSH stimulation in the past. However, going forward, I do not think there is any proven connection between human thyroid dyshormonogenesis, and cancer, except via TSH action, although one wonders whether there could be some other genetic link. I also believe, in the absence of any compelling data, that one should be more aggressive about a <1cm lesion, in this youth, than in an adult.
Surely he is at low risk in view of ablation and negative TG with TSH high. (I presume he had detectable TG at some point??) I think a common opinion would be that his TSH could be moderated toward 0.4uU/ml, and that he could be followed by yearly stimulated TGs. My own personal preference (being from the old school) would be, one year after ablation, to do another 131-I scan and TG. Assuming both are .totally negative, I would at that point be satisfied to follow with stimulated TGs on an annual basis.
Regards,
L De Groot, MD