What is thyroid cancer?
The thyroid gland is located in the lower front of the neck, below the voicebox (larynx) located in the upper part of the neck, and above the collarbones. Thyroid cancer (carcinoma) usually appears as a painless lump in this area. In most cases, the lump affects only one side, and the results of thyroid function tests (blood tests) are usually normal.
There are four main types of thyroid cancer (papillary, follicular, medullary and anaplastic). Since the vast majority are either papillary or follicular, and these are the only two types treatable with radioiodine, this brochure will focus on these two types.
