Pituitary adenoma refers to an abnormal growth of the pituitary gland.
The main hazards of pituitary adenoma to human body are
1, metabolic disorders and organ damage caused by excessive secretion of pituitary hormones.
2.Tumor compression restricts the normal function of pituitary gland, resulting in insufficient hormone secretion.
3, tumor compression of important structures in the pterionic saddle area, such as optic nerve, cavernous sinus and hypothalamus. The vast majority of pituitary adenomas are benign, and the tumors occur in the pituitary gland and its surrounding tissues without metastasis to distant sites. Treatment of pituitary adenomas includes removal of the tumor or inhibition of its growth.
Etiology
Abnormal proliferation of tissue cells in the pituitary gland forms pituitary adenomas, but the exact cause of the tumor is not known. The pituitary gland is a soy-sized gland located at the base of the skull, behind the nose and between the ears. Although the pituitary gland is small, it affects almost every part of the body. It secretes hormones that regulate important functions, including growth and development, blood pressure and body repair. A small number of pituitary adenomas have a genetic predisposition, while most do not exhibit genetic factors. Scientists speculate that genetic changes play an important role in the development of pituitary adenomas.
Morbidity
Pituitary adenomas are common benign intracranial tumors, second only to gliomas and meningiomas in terms of incidence. Pituitary adenomas can occur at any age, but they are more common in adults and less common in children. Those with a family history of the disease, such as multiple endocrinomatosis (type I), have an increased chance of developing pituitary adenomas. In patients with multiple endocrinomatosis (type I), tumors develop in multiple glands of the endocrine system.
Clinical symptoms
Pituitary adenomas are capable of causing endocrine dysfunction and pressure symptoms. In terms of gross morphology, pituitary adenomas larger than 1.0 cm in diameter are called macroadenomas, those smaller than 1.0 cm are called microadenomas, and those larger than 3.0 cm are called giant adenomas. Macroadenomas can produce pressure on the pituitary gland and surrounding structures. Those with clinical symptoms of endocrine disorder are called functional pituitary adenomas, while those without endocrine disorder are called non-functional pituitary adenomas.
I. Symptoms caused by tumor compression
1.Headache: early stage is mild and intermittent, mainly located in posterior orbit, forehead and bilateral temporal area. Tumor necrosis and bleeding can show severe headache.
2.Vision loss and visual field loss: tumor compresses the optic cross and optic nerve, causing visual impairment and blindness in serious cases.
3. Nausea and vomiting: the tumor increases the intracranial pressure.
Symptoms of low hormone level caused by tumor
1. Fatigue
2. Lack of energy
3. Chilliness
4. Constipation
5. Low blood pressure
6. Hair loss
7. Sexual dysfunction
8. Weight loss or gain
Symptoms caused by increased hormone level due to tumor
Functional pituitary adenomas usually overproduce hormones, resulting in a variety of biochemical reactions. Different types of functional pituitary adenomas lead to different signs and symptoms.
1. Adrenocorticotropic hormone adenoma (ACTH).
ACTH secretes adrenocorticotropic hormone, which stimulates the adrenal glands to secrete cortisol hormone. Excessive secretion of cortisol hormone by the adrenal glands can produce Cushing’s syndrome, the manifestations of Cushing’s syndrome include
(1) Centripetal obesity
(2) Full-moon face
(3) Buffalo back
(4) Hypertension
(5) muscle weakness
(6) Easy trauma
(7) purpura
(8) Skin tags
2. Growth hormone adenoma: Growth hormone adenoma secretes too much growth hormone. The effects of excessive secretion of growth hormone include
(1) Broad facial appearance
(2) Enlarged extremities
(3) Excessive sweating
(4) High blood pressure
(5) Heart disease
(6) Degenerative joint disease
(7) Malocclusion of teeth
(8) Adolescents may manifest as gigantism
3. Prolactin adenoma.
Pituitary adenomas secrete too much prolactin resulting in decreased levels of sex hormones (estrogen for women and testosterone for men). High prolactin affects men and women differently.
(1) In women, hyperprolactin can cause
① Menstrual disorders
(2) Amenorrhea
③ Lactation
(2) In men, prolactin adenoma can cause hypogonadism with signs and symptoms including
(i) breast development
② Erectile dysfunction (impotence)
③ Infertility
④ Hair loss
⑤ Atrophy of sexual characteristics
4. Thyrotropin adenoma.
Pituitary adenoma secretes too much thyrotropin hormone, causing the thyroid gland to produce too much thyroxine. It is a rare cause of hyperthyroidism. Hyperthyroidism can promote the body’s metabolism, including: sudden weight loss, tachycardia or irregular heart rate, mental changes or irritability.