Pituitary tumors: what they are, symptoms and treatment

Table of Contents

What is the pituitary gland

The pituitary gland it’s a small gland, whose main function consists in the secretion of hormones with which it regulates the functioning of almost all the endocrine systems of our body (thyroid, adrenal glands, ovaries, testicles). IS located at the base of the brain, just behind the nose, is 5-7 mm in size and is divided into two distinct lobes: adenohypophysis (or anterior pituitary) and neurohypophysis (or posterior pituitary).

The anterior pituitary produces the following hormones:

L’growth hormone (GH) which acts directly on the tissues, is the main hormone necessary for growth, stimulates the deposition of calcium in the bone tissue and the proliferation of cartilage cells, increases the mass of skeletal muscles and stimulates protein synthesis;
there prolactin (PRL) acts on the mammary gland by stimulating the secretion of milk after childbirth;
L’thyrotropic hormone (TSH) acts on the thyroid, promoting the release of the hormones it produces and, consequently, its proper functioning;
L’adrenocorticotropic hormone (ACTH) determines the synthesis and secretion of hormones of the adrenal cortex and stimulates lipid and glucose metabolism.
L’follicle-stimulating hormone (FSH) and theluteinizing hormone (LH) act on the gonads; in the ovaries the first stimulates the formation of follicles and the secretion of estrogen, the second the formation of the corpus luteum and the secretion of progesterone; in the testis, LH works by promoting testosterone secretion, while FSH promotes sperm production and formation.

The posterior pituitary produces:

L’oxytocin: produced and released during sexual intercourse, childbirth and breastfeeding;
L’antidiuretic hormone (ADH) which determines fluid retention and an increase in volume.

Pituitary tumors

The pituitary gland may be affected by small benign tumors, which are called pituitary adenomas. In fact, the term adenoma defines a benign tumor that develops from glandular cells. Pituitary tumors account for about 10% of all intracranial cancers and in 90% of cases they involve the anterior pituitary. Most of these tumor masses grow very slowly and it does not cause obvious disturbances.

Pituitary adenomas can affect any age, including the pediatric one, however, the greatest incidence is found between 30 and 60 years. In many cases the diagnosis is incidental while performing CT (computed tomography) or magnetic resonance imaging of the brain for other reasons (for example, a head injury). Sometimes, in fact, they remain unrecognized for years without causing disturbances.

Based on their size, they are classified into micro-adenomas (with a diameter of less than 1 cm) and macro-adenomas (greater than 1 cm); moreover they can be classified according to the clinical picture, characterized or not by the excessive secretion of one of the pituitary hormones and are divided into:

functioning: cause an increase in the secretion of a certain active hormone;
not working: consisting of tumor cells without a certain hormone secretion, which are often associated with malfunctioning of the surrounding endocrine cells with consequent deficit in the correct functioning of the pituitary gland.

Carcinomas (malignant tumors) of the pituitary gland they are very rare and present with metastases in other organs and in particular in the brain, spinal cord and meninges already at diagnosis.

Symptoms

The symptoms associated with the presence of a pituitary tumor are of three types:

indicative of the presence of a mass occupying space in the region of the sella turcica (ed. that is the bone structure at the base of the brain that contains the pituitary);
of an excess of hormonal secretion;
of a deficit of hormonal secretion.

In the first case one headache particularly resistant to analgesic / anti-inflammatory therapy, perhaps associated with a visual impairment (especially difficulty in seeing the lateral fields) can be a symptom of suspicion.

In woman alterations in the menstrual cycle (oligomenorrhea or amenorrhea) are generally the first indicator of a hormonal problem: in fact both hypersecretion and hyposecretion of the pituitary can disturb the delicate balance of the pituitary-gonadal axis.

In theman one of the main symptoms associated with the presence of pituitary tumors is erectile deficit, as well as, even more specifically, a reduction in libido, especially in the case of those tumors that produce prolactin.

Also there difficulty in conception it can be a consequence of the presence of a pituitary tumor, in the woman but also in the man. Often these tumors are, in fact, diagnosed following examinations for the couple’s infertility.

There are also peculiar symptoms that can help us identify the presence of tumors that produce GH or ACTH. In the first case, particular attention must be paid toenlargement of the hands and feet with the need to change the rings or the size of the shoes, as well as the appearance of sweating or a greater tooth spacing associated with changes in the face: all signs and symptoms of a possible hypersecretion of GH.

In the second case, the appearance of red stretch marks on the abdomen or thighs, rapid and unexplained weight gain associated with muscle hypotrophy of the limbs, the onset of diabetes and hypertension, especially at a young age, a higher frequency of bruising and in women the appearance of hirsutism or disturbances of the menstrual cycle can lead to the presence of a pituitary tumor that produces ACTH.

The appearance of polydipsia (need for having drink large amounts of water, more than 3-4 liters per day) and polyuria (the need to urinate a lot) can be an alarm bell for the presence of a tumor affecting the posterior pituitary gland with consequent deficiency of the anti-diuretic hormone.

Finally, the most nonspecific set of symptoms is important fatigue, reduced stress tolerance, hypotension, tendency to hypoglycemia, ideo-motor slowdown, hyporeflexia, cold intolerance, constipation and weight gain they could reflect a deficiency in the functioning of ACTH and TSH and configure those pictures of hypothyroidism and adrenal hypocorticism of pituitary origin that often accompany the presence of tumors of the pituitary gland.

Diagnosis

The diagnosis it’s not always easy as the symptoms can also be very nonspecific. That is why the first step should always be a careful medical examination during which the specialist takes note of all the signs and symptoms complained of by the patient. Based on an initial evaluation, in case of real suspicion of pituitary pathology, they will be hormone levels assessed with a blood sample. When it is suspected that the tumor has reduced the function of the healthy part of the pituitary, both the levels of the hormones directly produced by the pituitary and those produced by the peripheral gland are evaluated. Finally, to confirm the diagnosis, theperforming an MRI of the pituitary gland with contrast medium that allows to highlight even very small lesions. The visual field examination can be useful in cases where there is a visual disturbance or when a macroadenoma is highlighted on the MRI.

Therapy

Treatment of these tumors can be surgical, medical and radiotherapy. Since pituitary tumors are quite rare, it is extremely important to go to specialized centers where you can have the best treatments and count on the presence of experienced doctors. To choose the most suitable treatment it is however essential to know if it is a benign form and take into account other factors such as tumor size, whether hormone is produced, and the type of hormone produced. In many cases, surgery remains the treatment of first choice; in tumors that produce prolactin it is preferable at the forefront of drug therapy. Instead, in cases of small and asymptomatic tumors, found incidentally, only follow-up is possible over time.

In collaboration with Dr. Nunzia Prencipe