Treatment Plan

Some form of surgery, radiation and hormone therapy is offered to patients with thyroid cancer. Chemotherapy may also be used. The combination of methods differs depending on the type of cancer.

Papillary and Follicular Thyroid Cancer

A near total thyroidectomy is the removal of the entire thyroid gland except for tissue around the four tiny parathyroid glands. This preserves parathyroid function, essential for maintaining calcium balance. Lymph nodes from the neck are examined for enlargement and those suspicious for cancer are removed. In some cases, lymph nodes from both sides of the neck are removed. A fine needle aspiration of a follicular or Hürthle cell lesion may look benign under the microscope. More tissue is required to determine if it is, in fact, malignant. Before the entire thyroid gland is removed, the nodule in question -- and possibly other areas -- are sampled and sent to the pathologist for examination under the microscope.

Thyroid hormone replacement is necessary after thyroidectomy; otherwise, the patient would become hypothyroid. In addition, lack of thyroid hormone triggers pituitary production of thyroid stimulating hormone (TSH), which would induce growth of remaining thyroid cancer cells.

Radioiodine therapy is used to destroy remaining thyroid cancer tissue left behind after surgery. The patient swallows a capsule containing iodine-131, which is taken up by thyroid cancer as well as normal thyroid tissue. Radioiodine is not effective against medullary thyroid cancer and Hürthle cell cancer.

In external beam radiation, a machine is directed onto the neck. X-rays from a linear accelerator are aimed to the surgical site to destroy remaining cancer cells. The patient is exposed to the radiation for a few minutes each day, five days a week, for about eight weeks.

Medullary Thyroid Cancer (MTC)

The treatment is total thyroidectomy with removal of lymph nodes. If there are no metastases (spread of cancer) at the time of surgery, the patient is monitored for recurrence. If there are metastases, the treatment depends on the size and growth rate of the metastatic lesions. Small and slow-growing metastases of medullary thyroid cancer in the liver may not cause any symptoms for years after the thyroidectomy and would only need to be monitored. Larger and rapidly growing liver metastases may require surgery. Thyroid C-cells do not absorb iodine. Thus, radioiodine treatment is not used in MTC. However, the patient may respond to external beam radiation or chemotherapy, which uses drugs to kill cancer cells. After surgery for MTC, the patient is followed for a rise in blood calcitonin and CEA levels. A rise in these markers indicates that MTC has recurred, and surgeons advocate a repeat examination of lymph nodes in the neck and to remove any that have developed MTC.

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This article was reviewed and updated June 2007.