There are two main systems that control the functions of the body. The first of these is the "nervous system", which takes its source from the brain and spinal cord and distributes throughout the body, and the second is the "hormonal system" or "endocrine system" that manages body functions by watching the blood constantly circulating in the body. These two systems work in conjunction with each other.

 

Hormones are chemical substances secreted by cell ensembles or glands in the body. There are two glands in the brain that belong to the endocrine system. The first is the pituitary gland, the second is the pineal gland. Tumors involving the pineal gland are very rare. The pituitary gland, located at the base of the skull and under the brain, is a vital organ that is the control center that ensures the secretion of many hormones in our body and the water balance of the body.

 

Tumors involving the pituitary gland are detected in 5-10% of all brain tumors. Pituitary adenomas are mostly benign tumors. Pituitary gland tumors show symptoms in the body in two ways. The first is the mass effect, in which very enlarged tumors cause symptoms by compressing the surrounding structures. In this case, especially the optic nerve near the gland is affected, resulting in decreased vision or loss of vision in the patient. If the tumor grows larger, loss of function of the nerves that make eye movements may also occur. When the pituitary gland reaches such a large size, the normal pituitary tissue will lose its function, and deficiency in various hormones secreted from the pituitary can also be seen. The tumor shows its second effect with excessive secretion of some hormones by enlarging the gland or without enlarging it. If the pituitary gland has grown to a size not exceeding 1 cm, these tumors are called microadenomas, and if they are larger than 1 cm, they are called macroadenomas. Adenomas that do not secrete hormones usually grow slowly and may remain asymptomatic for years. Those who secrete hormones show early symptoms due to the effects of hormones in the body.

 

Pituitary gland; It consists of two parts, anterior pituitary and posterior pituitary. Pituitary gland tumors are mainly tumors of the anterior pituitary. Tumors arising from here give symptoms either due to excessive hormone secretion or due to excessive growth and pressure and spread to the surrounding tissues.

 

The hormones secreted from the anterior pituitary and their functions are as follows:
 

• Prolactin hormone: It ensures the secretion of milk from the breast.

• Growth hormone: controls carbohydrate, fat and protein metabolism in the body. It ensures the balanced growth of the body, especially during adolescence.

• Adrenocorticotrophic hormone: regulates the secretion of vital, cortisol from the adrenal glands. 

• Thyroid stimulating hormone: It ensures the secretion of thyroid hormones from the thyroid gland. 

• Gonadotrophic hormones: they control the functions of the reproductive organs. 

 

The body's secretion of more hormones than it needs causes an increase in the functions of that hormone or hormones in the body. In this case, for example; If excessive prolactin is secreted, milk comes from the breast even though the patient is not pregnant. If excess growth hormone is secreted in an adult, shoes may start to feel narrow as a result of excessive growth of the body.

 

The posterior pituitary secretes antidiuretic hormone, which regulates the urine output from the body, and the hormone called oxytocin, which ensures uterine contraction at birth. Tumors of the posterior pituitary are almost never seen. 
 

Frequency

Pituitary adenomas are in the 3rd rank among all tumors located in the head, after those arising from the brain itself and its membrane. So it is a relatively common tumor. The reasons for its occurrence are not fully understood. They are rarely seen together with hereditary diseases.

 

Complaints and Findings

Pituitary adenomas cause complaints either according to the type of hormone secreted or because of the pressure of the tumor on the surrounding tissues by growing too much. A type of hormone with various effects is secreted from the pituitary gland, and such adenomas show symptoms according to the effect of the hormone secreted in excess. For example; If the hormone that produces milk (prolactin) is secreted excessively, it gives symptoms such as milk coming from the breast and menstrual disorder in women. In men, conditions such as decreased sexual power, decrease in beards, enlargement of breasts may occur. If the growth hormone is secreted excessively, symptoms such as enlargement of the hands, feet and tongue, excessive snoring, breathing problems, diabetes and high blood pressure occur. If there is an excessive release of cortisol, severe symptoms such as excess fat accumulation in the body, skin rashes, treatment-resistant diabetes and the emergence of high blood pressure are seen. In addition, some patients may experience a headache that spreads to the eyes and neck as the pituitary tumor enlarges and stretches the cerebral cortex. If the tumor presses on the optic nerve, visual disturbances may occur. The most typical visual impairment is the patient's inability to see both sides clearly. In extremely large tumors, this can progress to blindness. Pituitary adenomas that do not secrete hormones, on the other hand, can cause a decrease in all pituitary hormones as they overwhelm the normal pituitary tissue. In this case, symptoms of hormone deficiency such as weakness, fatigue, low blood pressure, dry skin, decreased sexual power may occur in patients. Rarely, a pituitary adenoma can bleed and sometimes cause sudden vision loss. This condition requires urgent surgical treatment.

 

Types of Pituitary Adenoma

Pituitary adenomas are divided into two groups as hormone-secreting and non-secreting adenomas. Hormone secreters are classified and named according to the type of hormone they secrete.

 

Diagnosis

In patients with pituitary adenoma findings, first of all, blood hormone tests and visual examination are performed. Pituitary Magnetic Resonance Imaging examination is required for definitive diagnosis. In Cushing's Disease, a blood sample may be required to be taken from the neighborhood of the pituitary gland by performing cerebral angiography very rarely.

 

Treatment

Endocrinology and Neurosurgery departments usually decide on the treatment planning of patients diagnosed with pituitary adenoma. Considering the patient's findings, size of the adenoma, and hormone status, there are three main types of treatment options:

 

1- Drug Treatment:It is the first choice especially in the treatment of prolactinomas and is an auxiliary method in other adenomas. The majority of prolactinomas respond well to this treatment. Some growth hormone-secreting pituitary adenomas can also be controlled with medication. It is possible to control excessive hormone secretion with medication. However, when the drug is discontinued, hormone secretion returns to its previous level in most patients. The patient may need to use the drug throughout his or her life.

 

2- Surgical Treatment:It is the first and most effective treatment option for all adenomas with compression findings except prolactinomas. Two main methods are used:

• Intranasal intervention: It can be applied with the help of a microscope or endoscopically. They are the most preferred methods today.

• Open surgery: It can be preferred in adenomas that grow and spread excessively into the brain. It is less used today.

 

The goals of surgical treatment are:

• Relieving the pressure of the tumor on the surrounding tissues, for example, on the optic nerves,

• To provide a better response to drug treatment by shrinking the tumor mass.

 

3- Radiation therapy:It is used in tumors that cannot be completely removed by surgery or that recur despite all treatments. Today, focused radiation therapy methods called Gamma and Cyber  Knife are mostly preferred.

 

Treatment Results

When all the treatment options mentioned above are used, more than 90% of pituitary adenomas respond well to treatments.
Today, in the surgical treatment of pituitary tumors, surgical treatment is preferred by entering through the nose. The rates of complications that the patient may encounter due to surgery are given below:

-Anesthesia complications %2.8 
-Carotid artery rupture %1.1 
-Damage to brain tissue %1.3 
-Hematoma inside tumor tissue that cannot be completely removed 2.9% 
-Visual loss %1.8 
-Paralysis in eye movements %1.4 
-Cerebral spinal fluid leak %3.9 
-Meningitis 1.5% 
-Perforation of the septum inside the nose %6.7 
-Nosebleeds %3.4 
-Sinusitis %8.5 
-Anterior pituitary hormone deficiency 19.4% 
-Insipid diabetes 17.8% 
-Death 0.9%