Healthtips

Thyroid nodules are abnormal growths or lumps in the thyroid gland. Most of these are benign with 5 to 10% diagnosed as cancerous. While thyroid nodules do not generally affect the function of the thyroid gland, sometimes they produce excessive amounts of thyroid hormones, leading to over activity of the thyroid gland or “hyperthyroidism”. This is a rare diagnosis, occurring in less than 1% of those having thyroid nodules. “Hypothyroidism” develops when the thyroid gland does not produce enough thyroid hormone, which regulates the way the body uses energy. A lack of thyroid hormone affects many body systems. The incidence of hypothyroidism tends to increase with age, with older women at highest risk. Both hyperthyroidism and hypothyroidism can be symptoms of thyroid nodules.

Radiation therapy is the only known cause of cancerous and non-cancerous thyroid nodules. It was commonly used in the mid 1950’s and 1960’s to treat enlarged tonsils, adenoids and thymus glands and to treat acne, but is no longer in use. The occurrence of thyroid nodules may also be genetic.

Most thyroid nodules are so small that they do not usually cause symptoms nor can they be felt. Large nodules may produce swelling in the neck. Some other symptoms include pain or a feeling of fullness in the neck or difficulty swallowing or breathing. The symptoms of hyperthyroidism include nervousness, rapid heartbeat, excessive sweating and weight loss. Fatigue, lethargy, depression, memory problems and constipation are all symptoms of hypothyroidism.

Thyroid nodules are diagnosed through a medical history and physical exam and are often discovered during a CT scan or ultrasound of the neck, chest or head done for another reason. It is unusual for a patient to discover thyroid nodules on their own.

There are no definite symptoms to identify a thyroid nodule as cancerous, but this is more likely the diagnosis if there is a single hard growth clearly different from the rest of the thyroid tissue, if it grows consistently over weeks to months, or does not easily move when felt. Hoarseness that will not go away is another symptom that may indicate a cancerous nodule.

Once thyroid nodules are detected, a thyroid-stimulating hormone test is generally administered to determine if the thyroid gland is functioning properly. At this point in their diagnosis, most patients are referred by their primary care provider to an endocrinologist, a specialist such as myself who treats patients with thyroid and diabetic conditions.

If I find that nodules are present, I may perform a fine-needle aspiration thyroid biopsy which is an outpatient procedure with 90% accuracy of diagnosis. I may also order thyroid hormone tests to determine whether the nodule is causing abnormal thyroid hormone levels. A calcitonin blood test is sometimes done when there is a family history of thyroid cancer or cancer of other endocrine glands. Thyroid ultrasound may be done to confirm the presence of the nodule, to evaluate multiple small nodules that do not go away or return after the fluid has been drawn out, or as a visual guide for a fine-needle aspiration biopsy. A thyroid scan may be used to determine if a nodule is causing hyperthyroidism. Most nodules that cause hyperthyroidism are non-cancerous and can be treated without surgery.

Treatment for thyroid nodules depends upon the type of nodule and severity of symptoms. Benign nodules that cause no symptoms are observed by your doctor over a period of time for any changes. Many stay the same or shrink without treatment. If they cause hyperthyroidism they are usually treated with anti-thyroid medications and radioactive iodine and surgery is uncommon.

A cancerous nodule is surgically removed and radioactive iodine may be prescribed after surgery to destroy any remaining thyroid tissue or cancer cells. If your entire thyroid gland is removed, you must take thyroid hormone medication for the rest of your life.

Since it is difficult to tell if you are suffering from thyroid nodules, I suggest to patients that they call their doctor if they have any kind of swelling that does not go away in two weeks, a hoarse voice with no cause that lasts longer than one month, difficulty swallowing, or symptoms of hyperthyroidism or hypothyroidism. With accurate, timely diagnosis, and treatment by an experienced specialist, most thyroid nodules can be effectively treated.