Thyroid disorders explained

Thyroid nodules and swellings
Swellings of the thyroid gland are common, affecting up to ten per cent of people, especially women. In some cases the swelling involves the whole gland, which is then known as a 'goitre', while in many there are individual swellings known as 'nodules'. These may range from as small as a millimetre to as large as several centimetres and may be clumps of thyroid cells or fluid filled cysts. The cause of these swellings is often not known, although in some parts of the world is linked to a deficiency of iodine.

Most nodules are not associated with symptoms, are never detected and are harmless (90 per cent are benign). Nodules can, however, indicate an underlying problem with the thyroid and there is always a slight chance that a thyroid nodule is cancerous, so it is important to have all growths assessed by your doctor. There are three main ways in which a thyroid nodule can cause problems:

Treating nodules
A biopsy of the nodule will show if it is benign, as most are, or malignant. If benign, it requires monitoring rather than treatment. If a biopsy is indeterminate, or it identifies a malignancy, surgery is the appropriate treatment. Most thyroid cancers are curable.

Thyroidectomy is done under general anaesthesia and takes about two hours. How much of the thyroid gland is removed depends upon what the surgeon finds when he begins the operation. During the operation the surgeon may send some thyroid tissue to the laboratory for a very quick examination (a procedure known as a 'frozen section'). If cancerous cells are present, the surgeon will proceed to remove more of the thyroid. If the cancer has spread outside the thyroid, the lymph nodes in the neck may also be removed.

Some patients will need to take radioactive iodine six weeks after their surgery. This treatment will destroy any residual cancerous tissue. All patients also will begin lifelong thyroid hormone replacement therapy.

Side effects: As with other surgery, the minor risks include infection, bleeding and scar tissue on the neck. Major side effects from surgery are rare and involve complications to neck structures close to the thyroid. For example, 1 percent of patients develop speech problems due to nerve damage. If the parathyroid glands are damaged during surgery, patients will require calcium supplements and possibly other drugs.