Q&A: What to Know About Pituitary Adenomas
CancerWise - April 2008
Pituitary adenomas are rare, noncancerous tumors that can cause serious diseases. If specialized treatment is not received, they can shorten life expectancy.
Answering questions about pituitary adenomas is endocrinologist Steven Waguespack, M.D., an associate professor in M. D. Anderson's Department of Endocrine Neoplasia and Hormonal Disorders and Department of Pediatrics. Waguespack and other experts in M. D. Anderson's multidisciplinary Pituitary Tumor Program treat children and adults with pituitary adenomas.
What is the pituitary gland?
The pituitary is a pea-shaped gland located at the base of the brain that controls the production of hormones from other glands in the body, such as the thyroid, adrenal and reproductive glands. The pituitary gland, or master gland, also secretes growth hormone (GH), which is responsible for growth in children and metabolic functioning in adults.
What is a pituitary adenoma?
A pituitary adenoma is a noncancerous tumor that arises from a cell within the pituitary gland.
If a tumor develops from a cell that makes a hormone, it's called a functioning tumor. Most pituitary adenomas are functioning. If a tumor develops from a cell that does not make a hormone, it's called a nonfunctioning tumor.
What are the types of pituitary adenomas?
Tumors that produce too much of a particular hormone cause specific diseases or tumor types.
Pituitary diseases and related hormones:
- Hyperthyroidism – thyroid stimulating
- Cushing's Disease – adrenocorticotropin
- Acromegaly – growth
- Gonadotroph tumor – follicle-stimulating/leutinizing
- Prolactinoma – prolactin
What are the symptoms for each condition?
Symptoms vary depending on the type of hormone that the tumor overproduces. Because these conditions are so rare and many symptoms can be related to other diseases, it often takes years for them to be properly diagnosed.
Hyperthyroidism symptoms include:
- Weight loss
- Heart palpitations and fast heart rate
- Intolerance to heat
Cushing's Disease symptoms include:
- Weight gain
- Growth retardation, delayed puberty in children
- Abnormal fat distribution
- Abnormal menstrual cycles
- Acne/abnormal hair growth in women
- Easy bruising
- Depression or psychosis
- Low bone mass (fractures)
Acromegaly symptoms include:
- Joint pain
- Cardiovascular disease
- High blood pressure
- Lack of a menstrual cycle
- Thick skin
- Enlargement of the hands and feet
- Excessive sweating
- Snoring and sleep apnea
- Gradual changes in facial appearance over many years
Gonadotroph tumor symptoms include:
- Vision loss
- Double vision
- Irregular menstrual cycles
- High testosterone levels in men
Prolactinoma symptoms in women include:
- Secretion of breast milk
- Loss of bone mass
- Infrequent or light menstrual cycles
- Lack of menstrual cycles
Prolactinoma symptoms in men include:
- Poor libido
- Secretion of breast milk (rare)
- Breast development (rare)
Symptoms in children may include delayed puberty.
In general, when tumors grow, they may press on the normal pituitary gland tissue, which decreases the secretion of pituitary hormones and causes the pituitary gland to malfunction. The tumors also may press on the optic nerves or other vital structures, causing vision loss, double vision, headaches and memory problems.
How many people are diagnosed with pituitary adenomas?
These diseases are rare. The incidence of acromegaly, for example, is three to four cases per million people per year.
How are pituitary adenomas diagnosed?
Pituitary adenomas can be diagnosed through examination of symptoms, magnetic resonance imaging (MRI) scans, and blood and urine tests that assess endocrine function.
How are pituitary adenomas treated?
Each type of tumor is treated differently. Endocrinologists need to determine whether the tumor is making too much of a hormone, and then determine if the tumor is affecting the normal functioning of the pituitary gland. We also need to assess the size of the tumor to determine if urgent surgical treatment is required.
Treatment may include surgery, medication (including hormone replacement therapy) and radiation therapy. Often more than one type of therapy is necessary to control the tumor and its hormone overproduction.
Where can patients find treatment?
It's very important for patients to receive treatment from experts who specialize in pituitary adenomas and who also see a high volume of patients. That's especially true if patients need surgery.
One of the concerns is that there's a possibility the pituitary gland could be damaged during surgery, so the experience of the neurosurgeon is very critical. The more surgeries he or she has performed, the better.
Patients should find a surgeon who performs at least 50 surgeries a year.
Why does a cancer center treat a noncancerous tumor?
Although the vast majority of pituitary tumors are not cancerous, we treat them here at M. D. Anderson because we have the expertise already in place.
We have a specialized medical team made up of endocrinologists, neurosurgeons, neuroradiologists, pathologists, neuro-ophthamologists and radiation oncologists. We meet regularly to review patients' cases and discuss our findings and treatment recommendations in a multidisciplinary fashion.
Because we specialize in these rare diseases, we also are involved in multi-center clinical trials, so patients have access to more treatment options and the latest experimental drugs being developed.