Pituitary Adenomas: Causes and Symptoms

September 10, 2019
Most pituitary adenomas are benign and slow-growing. You can identify them because they remain inside the pituitary gland or in its adjacent tissues.

Pituitary adenomas are abnormal growths of cells within the pituitary gland. They attach to the hypothalamus by a thread of nerves and blood vessels.

Most pituitary adenomas are benign and slow-growing. Doctors can identify them because they either remain inside the gland or in its adjacent tissues. It’s for this reason that they don’t spread to other parts of the body.

Some pituitary adenomas can cause the pituitary gland to produce excess hormones. However, others cause the gland to produce very few hormones.

Types of Pituitary Adenomas

A drawing of the pituitary gland and its location inside the head.

The hormones produced by the pituitary gland regulate very important functions in your body. These functions have to do with development, metabolism, stress response and the functions of the sexual organs through the thyroid. They also help with the adrenal glands, ovaries, and testicles.

The pituitary gland “lives” inside the central nervous system and it regulates many basic functions of our bodies.

The causes of pituitary adenomas are unknown. However, some do have hereditary components. Thus, they’re classified according to their functionality:

  • Functional tumors are those that produce too many hormones and therefore can cause various problems to the body. Thus, the symptoms of this vary depending on the affected hormone.
  • Non-functional tumors don’t produce hormones. Thus, any symptoms are directly related to their growth.

What causes pituitary adenomas?

Pituitary gland tumors often have no clear cause. They often go undiagnosed because their symptoms are similar to those of many other diseases that are more frequent.

However, some of the diseases related to abnormal hormone levels are:

  • Cushing syndrome: These people have an accumulation of fat on their face, back, and chest. However, they often lose weight in their arms and legs.
  • Acromegaly: This is a disease in which the hands, feet, and face are larger than normal.
  • Sex hormones in the pituitary gland affect estrogen and testosterone. These can lead to milk production in women even if they’re not pregnant or breastfeeding. They may also decrease their libido.

Also read: 14 Signs that Indicate High Cortisol Levels

Symptoms of Functional Pituitary Adenomas

A doctor checking for hyperthyroidism.
Functional adenomas can produce a hormonal alteration in the body depending on the location of ​​the affected pituitary.

The symptoms of functional adenomas depend on the specific hormone produced in excess. Some of these hormones could be:


An excess of this hormone causes alterations in menstrual cycles, breast milk flow without breastfeeding, male impotence, headache and loss of vision.

Corticotropin Hormone (ACTH)

There are symptoms such as weight gain when there is too much corticotropin hormone. Also, there may be a lump at the nape of the neck or violet streaks on the skin, bone fragility, or mood swings. There may also be irregular menstruations present.

Growth Hormone

Elevated levels of growth hormone can cause symptoms such as excessive body growth or numbness in the hands and fingers. Also, there may be joint pain and headaches.

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Thyroid-Stimulating Hormone (TSH)

An excess of TSH will lead to symptoms such as irregular heartbeat, tremors, weight loss, difficulty sleeping and sweating.

Symptoms of Nonfunctional Adenomas

These types of tumors generate complications due to their growth by not affecting any functional zone. They either exert pressure on the pituitary gland or just damage it.

Pituitary adenomas also prevent the gland from secreting adequate levels of hormones. For example, when the level of a specific hormone is too low, then the gland or organ controlled by this hormone won’t work properly.

The most common symptoms of a non-functional adenoma are:

  • Headache and loss of vision.
  • Loss of body hair.
  • Less frequent or absent menstrual periods.
  • In men, there may be loss of facial hair, impotence, and growth of breast tissue.
  • A decreased libido.
  • Slower growth and sexual development in children.

Treatment for Pituitary Adenomas

Overall, there are several treatment options for pituitary adenomas. They either involve removing the tumor, controlling its growth and/or treating hormone levels.

  • Rojas, D. (2017). MANEJO DE LOS TUMORES DE HIPÓFISIS. Revista Médica Clínica Las Condes. https://doi.org/10.1016/j.rmclc.2017.01.008

  • Witte, F. (2005). Trastornos de la hipófisis. In Mente y cerebro. https://doi.org/10.1017/CBO9781107415324.004

  • Nieman, L., & Swearingen, B. (2010). Síndrome De Cushing Y Enfermedad De Cushing. Bioscientifica.