Most Are Benign
Doctors' dont "treat" thyroid nodules
unless there is concern for cancer
or they get big enough that they cause problems.
Solitary nodules are more concerning for cancer than thyroids with multiple nodules in them. If there is a concern for ca they are biopsied. If worrisome, the half portion of the thyroid with the nodule is removed, not just the nodule. See my comment below for more.