Nontoxic Nodular Goiter

Causes

The exact causes of nontoxic goiter are not known. In general, goiters may be caused by too much or too little thyroid hormones. There is often normal thyroid function with a nontoxic goiter. Some possible causes of nontoxic goiter include:

• Heredity (family history of goiters)
• Regular use of medications such as lithium , propylthiouracil , phenylbutazone, or aminoglutethimide
• Taking a lot of substances (goitrogens) that inhibit production of thyroid hormone—common goitrogens include foods such as cabbage, turnips, brussel sprouts, seaweed, and millet
• Iodine deficiency—Iodine deficiency is very rare in the United States and other developed countries, due to the use of iodized table salt; this is a primary cause of goiter in other parts of the world, particularly in mountainous areas, or areas that experience heavy rainfall or flooding

Risk Factors

The following factors increase your chance of developing nontoxic goiter:

• Sex: female (nontoxic goiter is more common in women than men)
• Age: over 40 years
• A diet low in iodine

If you have any of these risk factors, tell your doctor:

• Family history of goiter
• History of radiation therapy to head or neck, especially during childhood

Symptoms

Nontoxic goiters usually do not have noticeable symptoms, unless they become very large. If you experience any of these, do not assume it is due to this condition. These may be caused by other, less serious health conditions. If these symptoms persist, see your doctor.

• Swelling on the neck
• Breathing difficulties, coughing, or wheezing with large goiter
• Difficulty swallowing with large goiter
• Feeling of pressure on the neck
• Hoarseness

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will be done. Your doctor may recommend a specialist. An endocrinologist focuses on hormone related issues.

Tests may include the following:

• Examination of the neck—to assess any thyroid enlargement
• Ultrasound —a test that uses sound waves to identify nodules of the neck and thyroid
• Blood tests—to assess levels of thyroid hormones (eg, thyroid stimulating hormone); thyroid autoantibodies tests may also be done
• Thyroid scan (scintigraphy)—a picture of your thyroid gland taken after you have been given a shot or drink of a radioisotope to show how your thyroid is functioning and exclude thyroid cancer
• Fine needle aspiration biopsy —a tissue sample is taken with a small needle to determine if it is benign or malignant (cancer)
• Barium swallow —a test to determine if the enlarged goiter is compressing the esophagus, thus causing swallowing difficulty
• X-ray of neck and chest for large goiters—to see if the trachea is compressed

Treatment

Nontoxic goiters usually grow very slowly. They may not cause any symptoms. In this case they do not need treatment.

Treatment may be needed if the goiter grows rapidly, affects your neck or obstructs your breathing .

If a nontoxic goiter progresses to the nodular stage, and the nodule is found to be cancerous, you will need treatment. Talk with your doctor about the best plan for you. Treatment options include the following:

Prevention

Be sure that your diet contains enough iodine.