Prolactinoma: Causes, Symptoms, Diagnosis, and Treatment
Endocrine System Topic Posted by David Mangusan Jr., PTRP
Prolactinoma is a type of benign (noncancerous) tumor that affects your pituitary gland. Prolactin is one of the hormones produced by the pituitary. It acts to stimulate the breast to produce milk during pregnancy. After the baby is delivered, the mother’s prolactin levels decline unless she breast feeds her infant. Every time the baby nurses, prolactin levels will rise to maintain milk production.
Prolactinoma is the most common type of pituitary tumor. Symptoms occur when too much prolactin is in your blood (hyperprolactinemia) or the tumor presses on surrounding tissues.
Causes
The cause of pituitary tumor is not fully understood. Researchers are conducting studies to fully understand why cells tend to abnormally grow. Most pituitary tumors are not passed from parents to offspring.
In some people, high blood levels of prolactin can be traced to causes other than a pituitary tumor.
In women, too much levels of prolactin in the blood often causes infertility and changes in menstrual cycles. In some, menstrual periods may disappear altogether. Also in others, periods may become irregular or menstrual flow may change. Other signs or symptoms may include
Diagnosis
To diagnose prolactinoma, the doctor will likely test for prolactin blood levels. Blood testing is done in women who have unexplained milk secretion or irregular menses or infertility and in men with impaired sexual function and, in rare cases, milk secretion.
If prolactin is confirmed to be high, the doctor will test thyroid function. In addition, he or she will also ask about other conditions that you may have and medications that you are taking. Some conditions and medications can cause prolactin secretion to rise.
Your doctor will request an MRI (magnetic resonance imaging), which is the most sensitive test for detecting pituitary tumors and determining their size. Your doctor will also look for damage to surrounding tissues, and perform tests to determine whether other pituitary hormone production is normal.
Treatment
The goal of treatment is to return secretion of prolactin to normal, reduce the size of the tumor, correct any visual problems, and restore normal pituitary function.
Treatment of prolactinoma includes medications or surgery. Surgery should only be considered if medical therapy cannot be tolerated or if it fails to reduce prolactin levels, restore normal reproduction and pituitary function, and reduce tumor size.
Other articles about the pituitary:
Source: National Endocrine and Metabolic Diseases Information Service. NIH Publication No. 02–3924, June 2002
Page Last Revised: November 27, 2010
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Prolactinoma is the most common type of pituitary tumor. Symptoms occur when too much prolactin is in your blood (hyperprolactinemia) or the tumor presses on surrounding tissues.
Causes
The cause of pituitary tumor is not fully understood. Researchers are conducting studies to fully understand why cells tend to abnormally grow. Most pituitary tumors are not passed from parents to offspring.
In some people, high blood levels of prolactin can be traced to causes other than a pituitary tumor.
Prescription Drugs. Prolactin secretion in the pituitary is normally suppressed by the brain chemical, dopamine. Drugs that block the effects of dopamine at the pituitary or deplete dopamine stores in the brain may cause the pituitary to secrete prolactin. These drugs include the major tranquilizers trifluoperazine (Stelazine) and haloperidol (Haldol); metoclopramide (Reglan), used to treat gastroesophageal reflux and the nausea caused by certain cancer drugs; and less often, alpha methyldopa and reserpine, used to control hypertension.Symptoms
Other Pituitary Tumors. Other tumors arising in or near the pituitary — such as those that cause acromegaly or Cushing's syndrome — may block the flow of dopamine from the brain to the prolactin-secreting cells.
Hypothyroidism. Increased prolactin levels are often seen in people with hypothyroidism, and doctors routinely test people with hyperprolactinemia for hypothyroidism.
Breast Stimulation also can cause a modest increase in the amount of prolactin in the blood.
In women, too much levels of prolactin in the blood often causes infertility and changes in menstrual cycles. In some, menstrual periods may disappear altogether. Also in others, periods may become irregular or menstrual flow may change. Other signs or symptoms may include
breast milk production in women who are not pregnant or nursingThe most common symptom of prolactinoma in men is impotence. Because men have no reliable indicator such as menstruation to signal a problem, many men delay going to the doctor until they have headaches or eye problems caused by the enlarged pituitary pressing against nearby eye nerves. They may not recognize a gradual loss of sexual function or libido. Only after treatment do some men realize they had a problem with sexual function.
loss of libido (interest in sex)
vaginal dryness
pain during intercourse
Diagnosis
To diagnose prolactinoma, the doctor will likely test for prolactin blood levels. Blood testing is done in women who have unexplained milk secretion or irregular menses or infertility and in men with impaired sexual function and, in rare cases, milk secretion.
If prolactin is confirmed to be high, the doctor will test thyroid function. In addition, he or she will also ask about other conditions that you may have and medications that you are taking. Some conditions and medications can cause prolactin secretion to rise.
Your doctor will request an MRI (magnetic resonance imaging), which is the most sensitive test for detecting pituitary tumors and determining their size. Your doctor will also look for damage to surrounding tissues, and perform tests to determine whether other pituitary hormone production is normal.
Treatment
The goal of treatment is to return secretion of prolactin to normal, reduce the size of the tumor, correct any visual problems, and restore normal pituitary function.
Treatment of prolactinoma includes medications or surgery. Surgery should only be considered if medical therapy cannot be tolerated or if it fails to reduce prolactin levels, restore normal reproduction and pituitary function, and reduce tumor size.
Other articles about the pituitary:
Source: National Endocrine and Metabolic Diseases Information Service. NIH Publication No. 02–3924, June 2002
Page Last Revised: November 27, 2010
[Top of Page]
