Just like Barb 135 said, do not rely on TSH only, insist on the other test. I too have Hashimoto thyroiditis and 6 nodules and all blood test comes back normal with the exception of Thyroglobulin AB, high......these are the antibodies that eventualy it will destroy my thyroid...Was your growth a nodule or something else? wish you luck!
My TSH results were always normal and I had multi-nodule goiter and one was pretty big. The cells within the thyroid nodule will determine if the thyroid should be removed (partially or totally).
The tests to determine the type of nodule (lump) within the thyroid are: Thyroid ultrasound, Scan and Biopsy. TSH levels determine the function of the thyroid and most doctors live by these results, which i've learned should not be so.
NO -- do NOT rely solely on the TSH test............ TSH is a pituitary hormone that can fluctuate greatly, even over the course of a day.
You need to have the tests for the active thyroid hormones, Free T3 and Free T4. You should also have tests to determine whether or not you have an autoimmune thyroid disease, such as Hashimoto's Thyroiditis (most often associated with hypothyroidism, but often present with normal levels, or hyperthyroidism). Sometimes, the body, for some unknown reason, sees the thyroid as "foreign" and produces antibodies to destroy it; this can be either Hashimoto's Thyroiditis or Graves Disease (most often associated with hyperthyroidism). The antibodies attack the thyroid steadily and surely, and as the attack progresses, healthy tissue is destroyed and the thyroid produces less and less of the necessary hormones, which ultimately leaves us hypo (some because the thyroid stops producing, others because they have to have the thyroid removed). This destruction process can take years (I now believe I've had it for at least 20+ yrs), or it can happen relatively quickly.
Was the growth on your thyroid a nodule or some other type of growth? Many of us with Hashimoto's have nodules on our thyroid that cause no problems (I, personally, have "multiple" nodules).
Whatever you do -- insist on the Free T3 and Free T4 tests, and even then, pay close attention; many people have results in the so-called "normal" range, but still have issues. Always make sure you get a copy of your lab report and note where your results fall, within the reference ranges; if your FT3 and/or FT4 are at or near the bottom of their ranges, you most likely have a problem and will begin having symptoms soon.
First thing is do you have symptoms that are typical of being hypothyroid? If you have any question as to what those might be, here is a link to a listing of typical hypo symptoms.
http://endocrine-system.emedtv.com/hypothyroidism/hypothyroidism-symptoms-and-signs.html
Next thing is that I suggest that you read this link about clinical treatment of hypothyroidism and then tell us what questions you still have about your diagnosis and treatment.
http://hormonerestoration.com/files/ThyroidPMD.pdf