I agree with Yuehan… I’ve not had to face …

the prospect of surgery, but I’d think at least 3+ times before actually considering it? Then about 27 times more before Doing IT!
By your ‘enlargement’, do you mean a ‘goiter’? I’d had one ages ago, long before the CIDP cropped up and it was biopsied and while it wasn’t optimal? [It decreased w/meds and was no longer an issue.]It was semi-functioning at that time. My own thyroid ‘died’ with a big bang – often called a thyroid storm, where your hands & feet swell awfully and that pain was my prelude to future pains. At that point, usually changing thyroid med doses can help immensely, but it’s got to be constantly checked and adjusted. At first every 3 months, then 2x a year, to once a year if you’re stable.
Do be aware that the endocrine system is a very complex set of glands!
Go web up ‘EndocrineWeb’ and learn about those glands. Each relies on signals from the ‘others’ to do a whole slew of jobs that keep us functioning well. Once one gland or set of glands goes off? Problems can and do ensue.
It is in part, testament for how hard it can be for docs, to diagnose us!
Just be sure that your T-3&T-4, plus the immune levels of those T-3’s and T-4’s are checked. Sometimes the #’s are soo above or below normal? You get more than one “*” after the test # results! It’s fun to watch docs’ eyebrows try to not RISE when reading these as they see you!
Thyroid for the most part is one of the easier glands to ‘fix’! Just learn about it and get treated right! Good luck and I hope you feel better in one little aspect of your life! [One doc I’ve had, calls it – Off the check-list’! I like those!]