Gigantism is a rare condition that causes abnormal growth in
children. This change is most notable in terms of height, but girth is affected
as well. It occurs when your child’s pituitary gland makes too much growth
hormone, which is also known as somatotropin. Early diagnosis is important.
Prompt treatment can stop or slow the changes that may cause your child to grow
larger than normal. However, the condition can be hard for parents to detect.
The symptoms of gigantism might seem like normal childhood growth spurts at
gland tumor is almost always the cause of gigantism. The pea-sized
pituitary gland is located at the base of your brain. It makes hormones that
control many functions in your body. Some tasks managed by the gland include:
- temperature control
- sexual development
- urine production
When a tumor grows on the pituitary gland, the gland makes far
more growth hormone than the body needs.
There are other less common causes of gigantism:
syndrome causes abnormal growth in bone tissue, patches of light-brown
skin, and gland abnormalities.
complex is an inherited condition that causes non-cancerous tumors on
connective tissue, cancerous or non-cancerous endocrine tumors, and spots of
endocrine neoplasia type 1 (MEN1) is an inherited disorder that causes
tumors in the pituitary gland, pancreas, or parathyroid glands.
is an inherited disorder that causes tumors in the nervous system.
the Signs of Gigantism
If your child has gigantism, you may notice that they’re much
larger than other children of the same age. Also, some parts of the body may be
larger in proportion to other parts. Common symptoms include:
- very large hands and feet
- thick toes and fingers
- a prominent jaw and forehead
- coarse facial features
Children with gigantism may also have flat noses and large
heads, lips, or tongues.
The symptoms your child has may depend on the size of the
pituitary gland tumor. As the tumor grows, it may press on nerves in the brain.
Many people experience headaches, vision problems, or nausea from tumors. Other
symptoms of gigantism may include:
- excessive sweating
- severe or recurrent headaches
- insomnia and other sleep disorders
- delayed puberty in both boys and girls
- irregular menstrual periods in girls
Is Gigantism Diagnosed?
If your child’s doctor suspects gigantism, they may
recommend a blood test to
measure levels of growth hormones and insulin-like growth factor 1 (IGF-1),
which is a hormone produced by the liver. The doctor also may recommend
an oral glucose tolerance test.
During an oral glucose tolerance test, your child will drink
a special beverage containing glucose, a type of sugar. Blood samples will be
taken before and after your child drinks the beverage. In a normal body, growth
hormone levels will drop after eating or drinking glucose. If your child’s
levels remain the same, it means their body is producing too much growth
If the blood tests indicate a pituitary gland tumor, your
child will need an MRI scan of
the gland. Doctors use this scan to see the size and position of the tumor.
Is Gigantism Treated?
Treatments for gigantism aim to stop or slow your child’s
production of growth hormones.
Removing the tumor is the preferred treatment for gigantism
if it’s the underlying cause.
The surgeon will reach the tumor by making an incision in
your child’s nose. Microscopes or small cameras may be used to help the surgeon
see the tumor in the gland. In most cases, your child should be able to return
home from the hospital the day after the surgery.
Surgery may not be an option. This can be the case if there’s
high risk of injury to a critical blood vessel or nerve. Your child’s doctor
may recommend medication if surgery is not an option. This treatment is meant
to either shrink the tumor or stop the production of excess growth hormone.
Your doctor may use the drugs octreotide or lanreotide to prevent the growth
hormone’s release. These drugs mimic another hormone that stops growth hormone
production. They’re usually given as an injection about once a month.
Bromocriptine and cabergoline are drugs that can be used to
lower growth hormone levels. These are typically given in pill form. They may
be used with octreotide. Octreotide is a synthetic hormone that, when injected,
can also lower the levels of growth hormones and IGF-1. In situations where
these drugs are not helpful, daily shots of pegvisomant might be used as well.
Pegvisomant is a drug that blocks the effects of growth hormones. This lowers
the levels of IGF-1 in your child’s body.
Gamma Knife Radiosurgery
Gamma knife radiosurgery is an option if your child’s doctor
believes that a traditional surgery isn’t possible. The “gamma knife” is a
collection of highly focused radiation beams. These beams don’t harm the
surrounding tissue, but they’re able to deliver a powerful dose of radiation at
the point where they combine and hit the tumor. This dose is enough to destroy
Gamma knife treatment takes years to be fully effective and to
return the levels of growth hormone to normal. It’s performed on an outpatient
basis under general anesthetic.
However, since the radiation in this type of surgery has
been linked to obesity, learning disabilities, and emotional issues in
children, it’s usually used only when other treatment options don’t work.
Outlook for Children with Gigantism
According to St. Joseph’s Hospital and Medical Center, 80 percent of
gigantism cases are cured with surgery. If the tumor returns or if surgery
cannot be safely attempted, medications can be used to reduce your child’s
symptoms and to allow them to live a long and fulfilling life.