Hi Mancos, Almost all of us had goiters, or multinodular goiters, some turns out aren't so benign after awhile. I hope the risk for you is low for anything at this point and not sure what they would do, but the first thought is imaging. Whole body scan, CT with contrast - that kind of thing if one is concerned. Then biopsy if these imaging have concerning reports.

For fatigues, T4 is not so great alone, then other factors Vitamin D, anemia and ferritin levels - all important.