What is prolactinoma?

Prolactinoma is a type of noncancerous tumor that develops in the pituitary gland, a small gland at the base of the brain. The pituitary gland plays a crucial role in regulating various bodily functions by producing hormones. Prolactinoma specifically affects the production of the hormone prolactin.

Prolactin is responsible for stimulating breast milk production in pregnant and breastfeeding women. However, in individuals with prolactinoma, the pituitary gland produces an excessive amount of prolactin. This overproduction can lead to a range of symptoms and health issues, both in men and women.

Prolactinoma symptoms

Prolactinoma is a condition characterized by the overproduction of the hormone prolactin due to a noncancerous tumor in the pituitary gland. The symptoms of Prolactinoma can vary in both men and women and may include:

• In women:

  • Irregular menstrual periods: Prolactinoma can disrupt the normal menstrual cycle, leading to irregular periods or even loss of menstruation (amenorrhea).

  • Milky discharge from the breasts: This condition, known as galactorrhea, causes the spontaneous production of breast milk, even in women who are not pregnant or breastfeeding.

  • Vaginal dryness: Decreased levels of estrogen due to high prolactin can result in vaginal dryness and discomfort.

  • Infertility: Irregular ovulation and disrupted menstrual cycles can make it difficult for some women to conceive.

  • Reduced libido: Prolactinoma may lead to decreased sexual desire and may affect sexual function.

• In men:

  • Erectile dysfunction: High prolactin levels can interfere with normal sexual function and result in erectile dysfunction.

  • Reduced libido: Just as in women, men with prolactinoma may experience a decrease in sexual desire.

  • Infertility: Prolactinoma can affect sperm production, potentially leading to infertility.

  • Breast enlargement: Some men with prolactinoma may develop breast tissue growth, a condition called gynecomastia.

• In both genders:

  • Headaches: Large Prolactinomas may press against nearby brain tissues, causing headaches.

  • Vision problems: As the tumor grows, it can compress the optic nerves, leading to vision problems and loss of peripheral vision in severe cases.

What causes prolactinoma? 

• Pituitary gland abnormalities: Most prolactinomas are believed to arise from abnormalities in the pituitary gland. These tumors can form when there is an issue with the regulation of cell growth in the pituitary gland.

• Hormonal imbalances: Certain hormonal imbalances may increase the risk of prolactinoma. For instance, an excess of estrogen, as seen in conditions like polycystic ovary syndrome (PCOS), can stimulate prolactin production and potentially lead to a tumor.

• Medications: Some medications, particularly antipsychotic drugs and certain antidepressants, can stimulate prolactin production and increase the risk of prolactinoma.

• Head injuries: Trauma or injury to the head, especially if it affects the pituitary gland, can sometimes lead to the development of prolactinoma.

• Genetics: While rare, there may be a genetic component in some cases. A family history of pituitary tumors can increase the likelihood of developing prolactinoma.

How do you diagnose prolactinoma?

• The initial step in diagnosing prolactinoma is a thorough discussion of your medical history and a physical examination. This helps the healthcare provider understand the patient's symptoms and any potential risk factors.

• A blood test to measure the level of prolactin in the blood is a key diagnostic tool. Elevated prolactin levels can be indicative of Prolactinoma. In some cases, additional blood tests may be performed to assess other hormones produced by the pituitary gland.

• If elevated prolactin levels are detected, an MRI scan of the brain is typically conducted. This imaging test helps visualize the pituitary gland and any tumors or abnormalities, including prolactinoma. The MRI scan can also determine the size and extent of the tumor.

• If the MRI shows that the prolactinoma is pressing against the optic nerves, visual field testing may be performed to assess any vision problems.

• Depending on the specific case and symptoms, additional hormone tests may be conducted to evaluate the function of the pituitary gland and other related hormones.

Treating prolactinoma

• Medication: Medication is often the first-line treatment for Prolactinoma. The two main types of drugs used are dopamine agonists, such as cabergoline or bromocriptine. These medications help reduce prolactin production by the tumor and shrink the tumor itself. They are effective in controlling symptoms, restoring normal hormone levels, and often reducing the size of the tumor. Patients typically need to take these medications long-term.

• Surgery: Surgical removal of the tumor may be necessary if the Prolactinoma is large, causing severe symptoms, or if medication is ineffective. Transsphenoidal surgery is the most common surgical approach for Prolactinoma. In this procedure, the surgeon accesses the pituitary gland through the nose, removing the tumor while preserving the surrounding healthy tissue.

• Radiation therapy: In rare cases where medication and surgery are not effective, or if the tumor is too large or invasive, radiation therapy may be considered. Radiation can help control the tumor's growth, but it may take several years for the full effect to be seen.

The choice of treatment depends on your condition, including the size of the tumor, hormone levels, and the presence of symptoms. Consult with your endocrinologist to create a personalized plan based on your specific condition.