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| Living With Thyroid Nodules
and Goiter |
Donald L. St. Germain,
M.D. Professor of Medicine and
of Physiology Dartmouth Medical School
1. Do You Have a Thyroid Problem?
Where Is the Thyroid Gland and What Does It Do?
The thyroid gland is a small, butterfly-shaped organ
that is located in the lower part of the front of the
neck between the voice box, or Adam's apple, and the
top of the breastbone. It lies in front and along the
sides of the windpipe, or trachea. A normal thyroid
gland is thin, difficult to feel and usually not visible.
Like other glands in the body, the thyroid makes and
releases chemicals into the blood stream. These chemicals
travel to all parts of the body and act as signals to
control and coordinate important body functions. Chemicals
that work in this way are called hormones. Other examples
of hormones are insulin, estrogen and growth hormone.
The thyroid gland releases two major hormones. These
are abbreviated T4 and T3 to indicate how many iodine
atoms are in each hormone molecule. T3 is the most potent
thyroid hormone and it affects the workings of almost
every organ in the body. Levels of thyroid hormone in
the blood affect heart rate, muscle strength, bowel
function, fat metabolism, energy level, hair growth
and mood.
What Problems Does the Thyroid Gland Experience? The
thyroid gland commonly experiences three types of problems:
underactivity, called hypothyroidism; overactivity,
called hyperthyroidism; and enlargement of the gland,
called a goiter.
Inflammation in the thyroid gland, called thyroiditis,
is the most common cause of goiters in younger individuals.
In the elderly, goiters usually result from the growth
of one or more lumps, called nodules, in the gland.
Goiters usually develop slowly, over many months or
years. In most cases, the thyroid continues to function
normally, meaning that hypothyroidism or hyperthyroidism
is not present. Nodules in the thyroid gland are common
in both younger and older individuals, though they become
more common as people age. Fortunately, most nodules
are benign growths that are not a cause of great concern.
How Are Goiters and Thyroid Nodules Diagnosed?
To diagnose a goiter or thyroid nodule, a doctor simply
examines the patient's neck, feeling for an enlarged
thyroid gland. The patient, a friend or a family member
may have noticed a lump in the lower part of the patient's
neck and called the doctor's attention to it. In some
cases, the lump or goiter may cause discomfort or a
feeling of pressure in the neck. On rare occasions,
the lump may interfere with swallowing or breathing
by pressing on the esophagus or trachea. Hoarseness
may also result from a large goiter or nodule.
Your doctor may tell you that he or she feels a "dominant
nodule" in the thyroid gland. This means the thyroid
contains several lumps, but one lump is considerably
larger than the others. Often, if a single nodule or
a dominant nodule is present, the doctor will recommend
that a biopsy be taken.
Several types of scans and sound wave, or ultrasound,
tests are available to take a better look at the thyroid
and to detect nodules. However, these additional tests
are usually unnecessary and add little more than additional
expenses to the evaluation. If there is any concern
that the enlarged thyroid might contain a cancer, a
biopsy of the gland or nodule is indicated. This is
best performed by a thyroid specialist or surgeon. The
doctor presses a very thin needle into the thyroid gland
and takes a sample of tissue from the nodule. This is
called a fine needle aspiration, or FNA. This type of
biopsy is similar to that used to diagnose lumps in
other organs, such as the breast. The tissue sample
is sent to the laboratory where a pathologist looks
at it under a microscope to determine if cancerous cells
are present are not. It is very important that the pathologist
examining the specimen has experience interpreting FNAs
on thyroid tissue. Sometimes, especially in the case
of small nodules, the FNA may be performed using a sound
wave probe as a guide. This is called an "ultrasound-guided
FNA".
The results of the FNA will show one of four different
patterns, and it is important that the patient and the
doctor discuss the importance of these results.
The most common result is that the biopsy shows only
normal, or benign, appearing thyroid tissue. This makes
the chance of cancer very unlikely. Usually all that
is needed in this case is a follow-up exam once or twice
a year to be certain that further enlargement does not
occur.
If the pathologist sees cells that may be cancerous,
the doctor will almost certainly recommend surgery to
remove the nodule or enlarged thyroid.
With some types of nodules, the pathologist cannot tell
if the tissue is cancerous or not. He or she may report
that the biopsy is "suspicious" or that it is from a
"follicular neoplasm". The chance that cancer is present
in this situation is less than one in five. Because
of this relatively high risk, doctors usually recommend
surgery.
The final result pattern that can occur with an FNA
is that the sample did not contain enough cells and
tissue to make a diagnosis. The pathologist will say
that the specimen was "inadequate". This is a frustrating
result for both the patient and the physician and usually
requires another FNA.
In some cases, the thyroid problem that causes the enlargement
of the lump will also cause the thyroid to become overactive
or underactive. Because of this, it is important that
all patients with a goiter or nodule have a thyroid
blood test, called a TSH level, to be sure that the
gland is functioning normally.
2. Understanding How Thyroid Problems Affect Your
Body, Mind and Family What Are the Physical Effects
of Thyroid Problems?
Most patients with a goiter or thyroid nodule have normal
thyroid hormone levels in their blood. Therefore, they
usually do not experience any problems related to abnormal
metabolism. However, if the enlargement of the thyroid
gland is severe, it may press on the windpipe or esophagus.
This can lead to breathing or swallowing difficulties,
or result in a hoarse voice.
What Are the Emotional Effects of Thyroid Problems?
Patients who have an enlarged thyroid or a nodule are
rightly concerned that they might have thyroid cancer.
Fortunately, while goiters and nodules are quite common,
thyroid cancer is quite rare. Most patients with a thyroid
nodule do not have thyroid cancer. Furthermore, thyroid
cancer, when it does occur, is generally a "well behaved"
type of cancer that usually does not spread beyond the
neck. It is often curable by surgery and radiation treatment.
Individuals can be reassured that finding a goiter or
a thyroid nodule will usually result in a good outcome.
What Are the Effects of Thyroid Problems on Family and
Friends?
Goiters and nodules can run in families and your doctor
will ask you whether other family members have these
conditions.
What Is Your Doctor Concerned About?
In the case of a goiter, it is important to make sure
the thyroid gland is functioning properly. A TSH blood
test can provide this information. If a very large goiter
is present, your doctor will ask if you have breathing
and swallowing problems due to the thyroid pressing
on the trachea or esophagus. Additional X-rays or breathing
tests may be needed to investigate this possibility.
If a nodule is present, then the doctor may need to
consider thyroid cancer, which is very rare. To determine
if the nodule is cancerous, the doctor may perform an
FNA.
3. How to Cope?
Living With a Newly Diagnosed Thyroid Problem Most individuals
with a thyroid nodule or goiter have normal levels of
thyroid hormone. Therefore, these conditions usually
do not adversely affect a person's overall health. The
first and most important concern for the patient is
whether the thyroid gland contains a cancer. Thyroid
cancer is rare and can be diagnosed with a biopsy. Not
all patients with a nodule or a goiter require a biopsy.
The need for this depends on several factors including
the size of the thyroid gland, how long it has been
enlarged, how many nodules are present, and whether
or not the nodules are making thyroid hormone. As a
general rule, a thyroid gland containing a single lump
should be biopsied, whereas goiters that consist of
several small nodules of about the same size can be
safely watched without the need for an initial biopsy.
Deciding on Treatment There are several treatment options
for thyroid nodules and goiter. If a biopsy suggests
that cancer may be present, then surgery to remove the
thyroid is the only option. Surgery may also be performed
if the thyroid has gotten so large that it is pressing
on the windpipe or esophagus and causing shortness of
breath or difficulty swallowing.
If the thyroid enlargement is not severe and does not
appear to be due to cancer, then treatment may simply
involve observation with doctor's examinations once
or twice a year. In some cases, having an individual
take a thyroid supplement may cause the goiter or nodule
to shrink somewhat. This is called "suppressive therapy"
and works by lowering the TSH level in the blood, thus
causing less stimulation of the thyroid gland. If shrinkage
occurs, it often requires several months to work, and
this treatment is not always effective. Suppressive
therapy must be done very carefully in the elderly since
excessive amounts of thyroid hormone could have adverse
effects on the heart and bones.
4. Getting Healthy and Staying Healthy
Nutrition and Prevention Unfortunately, we do not know
what usually triggers thyroid enlargement or thyroid
nodules. So, there is no effective way to prevent these
conditions.
A healthy thyroid gland does need enough iodine to make
its hormones. In some parts of the world, especially
in Africa, China and some areas of southern Europe near
the Mediterranean Sea, the amount of iodine in the diet
is very low. This can make it difficult for the thyroid
gland to function properly. Often the gland enlarges
to form a goiter as it tries to pull in all the iodine
it can.
In the United States and most other parts of North America,
enough iodine is present in the diet to allow the thyroid
to work very efficiently. This is because iodine is
actually added to salt and some foods because of its
nutritional importance. In addition, many multivitamin
tablets contain beneficial amounts of iodine.
As in the case of many nutritional elements, too much
of a good thing can cause problems. In the case of the
thyroid, too much iodine can make it difficult for this
gland to function properly. This is especially true
if the thyroid is already struggling under an immune
system attack. In that case, the extra iodine may actually
worsen a hyperthyroid condition such as Graves' disease
and cause the levels of T4 and T3 in the blood to rise
even higher. In other situations, such as Hashimoto's
thyroiditis, where the thyroid has been damaged by the
immune system, excessive amounts of iodine can drive
the thyroid into an underactive state.
Therefore, one needs to be very careful when using nutritional
supplements such as seaweed or kelp that contain large
amounts of iodine. In general, such supplements are
not needed in those regions where iodine intake is already
sufficient. In that setting, such supplements often
do more harm than good.
Some practitioners of alternative medicine use various
types of "immunotherapy" to treat immune system problems.
In the case of thyroid diseases, there is no evidence
that these therapies are effective. As with the case
of using excessive iodine, they could conceivably make
a thyroid condition worse.
Working With Your Doctor You and your doctor should
work as a team when coping with a thyroid problem. The
initial stages of treatment may require relatively frequent
visits, at one to two month intervals, to discuss treatment
options and adjust medications. It is important to keep
you doctor informed about how you are feeling and whether
you are having any side effects from your treatments.
This is particularly important for elderly patients,
who may have a heart condition or be more likely to
develop a problem during therapy.
Many primary care physicians do a good job of caring
for patients with thyroid conditions. However, if your
questions are not being answered to your satisfaction,
or you feel as though you are not making progress with
your therapy, then ask for a second opinion from an
endocrinologist. An endocrinologist is physician who
specializes in treating thyroid problems and other hormonal
conditions. A referral may be important if you have
a thyroid nodule that requires biopsy. Referrals to
an endocrinologist and an ophthalmologist are also important
if you have Graves' eye disease.
Treatment Outcome Once a thyroid condition has been
properly diagnosed and treated, an individual can usually
resume a normal life without undue concern for her or
his thyroid gland.
Related Information:
Like Gore, 4 Out of 10 Develop Thyroid Lumps
Hyperthyroidism Library
Graves' Disease Library Medical Encyclopedia: Thyroid
Gland
Medical Encyclopedia: Nodule
Donald L. St. Germain, M.D.
Dartmouth Medical School
http://www.dartmouth.edu/dms/
Date Published: Dec. 29, 1999
Date Reviewed: Dec. 29, 1999
Donald L. St. Germain, M.D., is a professor of Medicine
and Physiology at Dartmouth Medical School. He received
his doctorate in medicine from the Johns Hopkins University
School of Medicine in 1976.
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