Prolactinoma – Symptoms and Causes
Overview
Prolactinoma is a benign (noncancerous) tumor that develops in the pituitary gland, located at the base of the brain. This type of tumor causes the pituitary gland to produce excessive amounts of prolactin, a hormone that affects reproductive functions.
When prolactin levels rise too high, they can decrease other important sex hormones like estrogen and testosterone.
As the most common hormone-producing tumor of the pituitary gland, prolactinoma can cause several health issues but is not life-threatening.
Most patients respond well to medication, which can bring prolactin levels back to normal range and reduce tumor size over time. Regular monitoring by healthcare providers helps ensure effective management of this condition.
Symptoms
Prolactinomas may not always produce noticeable symptoms. When symptoms do appear, they typically result from either excess prolactin in the bloodstream (hyperprolactinemia) or pressure from the tumor itself.
Gender-Specific Symptoms
For women:
- Irregular or absent menstrual cycles
- Unexpected breast milk production (when not pregnant or nursing)
- Discomfort during sex due to vaginal dryness
- Increased facial and body hair
- Acne outbreaks
For men:
- Difficulty achieving or maintaining erections
- Reduction in body and facial hair
- Decreased muscle mass
- Breast enlargement (gynecomastia)
Common Symptoms in Both Genders:
- Fertility problems
- Osteoporosis (weakened bones prone to fractures)
- Decreased sexual desire
Symptoms from Tumor Pressure:
- Vision changes or loss
- Headaches
- Reduced production of other pituitary hormones
Women before menopause often notice symptoms earlier when tumors are smaller, typically because of menstrual irregularities.
Men and postmenopausal women frequently detect the condition later when tumors have grown larger and cause headaches or vision problems.
When to See a Doctor
Visit your doctor if you notice any symptoms that might point to a prolactinoma. Early diagnosis can lead to better treatment outcomes.
If you’re planning pregnancy or are already pregnant and have a prolactinoma, speak with your healthcare provider promptly. Your treatment plan might need adjustments, and additional monitoring may be necessary during this time.
Causes
Brain Control Centers
The pituitary gland sits at the base of the brain. Though small, it affects nearly every part of the body. This bean-shaped gland makes hormones that control growth, metabolism, blood pressure, and reproduction.
The hypothalamus works closely with the pituitary gland to manage hormone production.
When someone develops a prolactinoma, the exact cause is often unknown. This tumor forms in the pituitary gland and disrupts normal function.
Hormone System
The body’s endocrine system includes several glands that work together:
- Pituitary gland
- Thyroid gland
- Parathyroid glands
- Adrenal glands
- Pancreas
- Ovaries and testicles
A prolactinoma makes the pituitary gland produce too much prolactin hormone. This excess prolactin leads to lower levels of sex hormones like estrogen and testosterone.
Other causes of high prolactin include:
- Certain medications
- Different types of pituitary tumors
- Kidney disease
- Underactive thyroid
- Pregnancy and breastfeeding
Risk Factors
Prolactinomas appear more commonly in women than men. Children rarely develop this condition.
In some cases, genetic factors may play a role. Inherited disorders that affect hormone-producing glands can increase someone’s chances of developing a prolactinoma, though this is uncommon.
Complications
Prolactinoma can lead to several health issues if not properly managed. These complications affect various body systems and functions.
Reproductive Problems
- Reduced fertility in both men and women
- Decreased production of sex hormones (estrogen and testosterone)
- Prevention of egg release during menstrual cycles in women
- Lower sperm production in men
Bone Health Issues
The decrease in sex hormones can weaken bones, leading to osteoporosis. This condition makes bones fragile and more likely to break from minor injuries or falls.
Pregnancy Risks
Pregnant women with large prolactinomas may experience tumor growth due to increased estrogen levels during pregnancy. This can cause headaches and vision changes that require medical attention.
Vision Complications
If a prolactinoma grows large enough, it can press against the nearby optic nerve. The first sign of this pressure is often loss of peripheral (side) vision, which may progress if untreated.
Hormonal Imbalances
Larger tumors can compress the healthy parts of the pituitary gland. This pressure may reduce the production of other important hormones, including:
- Other regulatory hormones
- Thyroid hormones (affecting metabolism)
- Cortisol (a stress hormone)
