Thyroid Goiter
Enlargement of the Thyroid
The term nontoxic goiter refers to enlargement of the thyroid which is not
associated with overproduction of thyroid hormone or malignancy. The thyroid can become very
large so that it can easily be seen as a mass in the neck. This picture depicts the outline
of a normal size thyroid in black and the greatly enlarged goiter in pink. There are a number
of factors which may cause the thyroid to become enlarged. A diet deficient in iodine can
cause a goiter but this is rarely the cause because of the readily available iodine in our
diets. A more common cause of goiter in America is an increase in thyroid stimulating hormone
(TSH) in response to a defect in normal hormone synthesis within the thyroid gland. The
thyroid stimulating hormone comes from the pituitary and causes the thyroid to enlarge. This
enlargement usually takes many years to become manifest.
This picture depicts the typical appearance of a
goiter in a middle aged woman. Note how her entire neck looks swollen because of the
large thyroid. This mass will compress the trachea (windpipe) and esophagus (swallowing tube)
leading to symptoms such as coughing, waking up from sleep feeling like you cant breath, and
the sensation that food is getting stuck in the upper throat. Once a goiter gets this big,
surgical removal is the only means to relieve the symptoms. Yes, sometimes they can get a lot
bigger than this!
Indications for Treatment
Most small to moderate sized goiters can be treated by providing thyroid hormone in the
form of a pill. By supplying thyroid hormone in this fashion, the pituitary will make
less TSH which should result in stabilization in size of the gland. This technique often will
not cause the size of the goiter to decrease but will usually keep it from growing any
larger. Patients who do not respond to thyroid hormone therapy are often referred for surgery
if it continues to grow.
A more common
indication for surgical removal of an enlarged thyroid [goiter] is to remove those glands
which are enlarged enough to cause compression on other structures in the neck such as
the trachea and esophagus. These patients will typically complain of a cough, a slight change
in voice, or nighttime choking episodes because of the way that the gland compresses the
trachea while sleeping. This X-ray shows how an enlarged right lobe of the thyroid has moved
the trachea to the patient's left. The trachea (outlined in light yellow) should be straight
from the mouth down to the lungs, but in this patient it is compressed and displaced far to
the left. The enlarged gland can even compress the blood vessels of the neck which are also
an indication for its removal. More about this on our page examining sub-sternal thyroids.
As always, suspicion of malignancy in an enlarged thyroid is an indication for removal
of the thyroid. There is often a dominant nodule within a multinodular goiter which can cause
concern for cancer. It should be remembered that the incidence of malignancy within a
multinodular goiter is usually significantly less than 5%. If the nodule is cold on thyroid
scanning, then it may be slightly higher than this. For the vast majority of patients,
surgical removal of a goiter for fear of cancer is not warranted.
Another reason (although not a very common one) to remove a goiter is for cosmetic
reasons. Often a goiter gets large enough that it can be seen as a mass in the neck. When
other people begin to notice the mass, it is usually big enough to begin causing compression
of other vital neck structures...but not always. Sometimes the large goiter causes no
symptoms other than being a cosmetic problem. Realizing of course, if its big enough to be
seen by your neighbors, something needs to be done...medications or surgery or it will most
likely continue to get bigger.
Return to Thyroid Gland introduction
More about Sub-Sternal Goiters (goiters which extend into the neck) More x-rays!
More about Thyroid Nodules
The role of Thyroid Ultrasound in examining thyroid masses
Characteristics of worrisome thyroid masses and when to Biopsy them
Introduction to Thyroid Cancer

