Microadenoma of the pituitary gland: symptoms, treatment, how dangerous
Microadenoma of the pituitary gland is a benign tumor of glandular cells of the organ, the size of which does not exceed 10 mm. the Tumor occurs quite widely. Among all brain tumors, about one-third of the cases occur in the pituitary adenoma.
The small sizes of microadenomas and the frequent absence of any symptoms do not allow to establish the exact figure of the prevalence of the tumor among the people. Moreover, in most cases it is detected accidentally, when examining about other diseases of the brain or its vessels.
Among patients with this diagnosis a little more than young women, although it is believed that the adenoma in General has no sex differences. This is probably due to the increased load on the pituitary gland during pregnancy, childbirth, lactation, when cells of the body have hard to produce hormones to maintain the proper functioning of other organs. In fact, microadenoma is hyperplasia of individual sections of the pituitary gland, leading to an increase in the size of the whole gland.
The pituitary gland is located at the base of the brain, in a special recess of the sphenoid bone, and its dimensions do not exceed 13 mm. Anterior lobe of the body (anterior pituitary) produces a large number of tropic hormones that regulate the activity of peripheral glands (thyroid gland, adrenal glands, ovaries in women). At such small size, the pituitary gland is crucial in the functioning of many organs and systems, violations in the work can cause serious pathology.
Microadenoma usually do not tend to give symptoms, and the cells may not produce any hormones. However, it happens that on the background of the tumor appears not only overproduction, but a deficiency of a hormone that may be the result of compression of giperplazirovannah portions of those cells which is not subjected to pathological changes. In all cases of hormonal imbalance, which can be a pathology of the pituitary gland, the patient should be evaluated for the subject microadenomas (adenomas).
Causes of pituitary microadenomas
Causes of pituitary microadenomas is not clearly disclosed, the research is ongoing, however the most likely factors leading to enhanced proliferation of the cells of the body are:
- The dysregulation of the functioning of the pituitary from the hypothalamus;
- The reduction of hormonal function of the peripheral glands, which acts by stimulating the pituitary gland, resulting in compensatory hyperplasia of its cells and the growth of microadenomas in the next;
- Genetic predisposition;
- Female gender and the associated increased load on the body (pregnancy, childbirth, frequent abortion, prolonged and uncontrolled intake of hormonal contraceptives);
- Central nervous system infections, trauma.
Depending on the structure of the tumor may be homogeneous or cystic microadenoma. The latter is a consequence of the small hemorrhages in the tissue neoplasm that should be considered solely as a symptom of the degenerative changes that do not affect the course of illness and prognosis.
Manifestations of pituitary microadenomas
In the anterior lobe of the pituitary gland produces hormones that enhance the activity of the thyroid gland, adrenal glands, ovaries, and regulates the General level of metabolism and tissue growth, therefore, the symptoms of microadenomas can be extremely diverse. Furthermore, the symptoms differ in men and women, in children or adults with the same tumor type.
Depending on the functional features are distinguished:
Microadenoma the inactive does not manifest itself for a long time asymptomatic and detected incidentally. If the cells microadenomas are able to produce any hormone, the clinic will be very pronounced and varied, the patient will not be able to ignore emerging changes, and to the endocrinologist. Hormonal active microadenoma does not apply to tumors, which can be tolerated without treatment, it always requires the participation of a specialist.
Symptoms microadenomas are defined by its functional ability. In most cases, when hormonal activity is increased, there is an excess of the hormone prolactin, and the tumour is called prolactinomas.
The signs of prolactinoma are reduced to dysfunction of the mammary and sex glands, but the women and men they will differ. Women have a prolactinoma causes an increase in body mass and triggers the secretion of milk the breast glands even in the absence of the need, inhibits the activity of the ovaries, resulting in infertility, leads to disruption of the menstrual cycle. The combination of these characteristics cannot be explained by functional impairment by stress, excessive stress or pathology of the other organs, so the diagnosis of prolactinoma is most likely.
Men microadenoma that produce prolactin, can be seen immediately, as the clinic is erased. Increase body mass and decrease in sexual function in men, which is not too care about their health and nutrition, it is justified, and the problems with potency can be deducted on unwanted weight. The appearance of secretions from the mammary glands can be a key symptom that will cause a patient to seek medical attention.
Hyperplasia of cells that produce thyroid-stimulating hormone stimulation of thyroid to increased secretion of its hormones. The result may be not only nodular goiter, and severe thyrotoxicosis in which patients significantly lose weight, emotionally labile, experiencing tachycardia and other arrhythmias, prone to hypoglycemia and other endocrine and metabolic disorders. This abnormality always requires timely correction. When removing pituitary tumors thyroid function usually returns to normal.
A special kind of pituitary microadenomas is somatotropinoma. This tumor secretes excessive amounts of growth hormone responsible for the growth of tissues and the organism as a whole. Feature growth microadenomas can be seen in the fact that manifestations in various cases appearing in childhood or in adults.
Children somatotropinoma of the pituitary gland causes enhanced and uncontrolled growth of the organism, which leads to gigantism. Often such patients suffer from various pathologies of the internal organs, the growth of which is not «time» for an increase in the whole organism, so in addition to tall patients are prone to diseases of the gastrointestinal tract, lungs, reproductive organs.
In adults the growth microadenoma can cause an increase in the individual parts of the body – face, hands, feet, what is referred to as acromegaly. Since the skeleton is already formed and the growth of the bones are closed, the increase in body growth does not occur, and the main effect of hormone manifested in the soft tissues. The patient’s coarse voice is more massive features, there is a tendency to arterial hypertension, diabetes insipidus, cancer.
Kortikotropina adenoma enhances the function of the adrenal cortex and is most often the cause of the disease Itsenko-Kushinga. Symptoms are to weight gain with deposition of fat mainly in the neck, abdomen, and thighs, the appearance of red purple stretch marks on the skin (striae), disturbances of body hair growth, particularly noticeable in women. In addition to external signs, often diagnosed arterial hypertension and steroid diabetes, associated with excess circulating cortisol in the body. Patients often suffer from mental disorders and behaviour.
Microadenoma that produces Gonadotrophins that can change the peripheral function of the gonads, leading to infertility, impotence, hyperplasia of the endometrium in women with risk of malignant transformation. These symptoms seldom suggest about microadenoma of the pituitary gland, so patients can get treatment from urologist or gynecologist from those secondary processes that caused the tumor.
Given the size of microadenomas and its location within the pituitary fossa, symptoms of lesions of the Central nervous system or the nerves nearby can be expected. The tumor can cause ophthalmic neurological syndrome characteristic of pituitary adenomas of larger size (macroadenoma), in any case, if its growth does not intensify. If there were headaches, impaired vision or smell, it is likely that microadenoma exceeded 10 mm, becoming macroadenomas that went beyond the pituitary fossa.
With further increase of the tumors, the symptoms will worsen, and endocrine disorders can join other symptoms – headache, dizziness, blurred vision, etc. to prevent this development, patients with asymptomatic microadenomas should be under observation, and if signs of growth of tumors prompted the removal of the tumor.
Syndrome radiographic changes is also not peculiar to microadenoma. The tumor does not go beyond the localization of the pituitary gland and does not cause disorders of bone structures, so to detect the x-rays impossible. This fact was the reason that for decades the tumor it was impossible to diagnose, and the diagnosis could be made only in the presence of the clinic. With the advent of modern methods of research and the possibility of MRI to a wide range predisposed persons, microadenoma was detected at the early stages of its development.
Most patients who are diagnosed with microadenoma pituitary, wondering if the tumor? Even when asymptomatic and accidentally detected microadenomas patient wants to know what to expect from such tumors in the future. Microadenoma with timely detection of any hazard. If you have symptoms of overproduction of hormones, the doctor will prescribe conservative treatment, or offer to get rid of the tumor. Asymptomatic microadenomas threat only to its further growth and transformation into macroadenoma when may be signs of compression of surrounding structures, even if in itself the tumor is inactive.
Dangerous are cases of hormonally active or growing microadenoma in which the patient refuses treatment. In this case, the possible irreversible changes in the internal organs caused by the overproduction of thyroid hormones, adrenal. Secondary hypertension or diabetes can cause life-threatening condition, and thyrotoxic heart sooner or later can stop. Such effects tumors can lead not only to a significant violation of life, but the death of the patient.
The danger of microadenomas in the absence of treatment due to the further growth of the tumor, which may be accompanied by pathology of internal organs, irreversible changes in vision, complications after surgical treatment of large pituitary adenomas (infection, brain damage, etc.).
Microadenoma and pregnancy
Since microadenoma often found in women of young age, who can plan the birth of children, the question successful pregnancy becomes very significant. In the inactive microadenoma pregnancy is not contraindicated, but women should carefully monitor the hormones in a timely manner and get an MRI to Refine tumor size. When indicated, it is better to get rid of, because pregnancy can cause rapid growth.
When hormonally active tumors need to normalize hormones through medication or surgery. If a woman suffers from prolactinomas, the pregnancy will be possible to plan only a year later, effective treatment. Of course, when it comes will have at least once a trimester to pass tests for hormones, to consult at the endocrinologist and the ophthalmologist, and drugs for the treatment of the tumor will have to cancel. Breastfeeding when microadenoma of the pituitary gland, as a rule, is contraindicated.
Diagnosis and treatment of pituitary microadenomas
If there are signs of increasing hormonal activity of peripheral glands, the specialist will always assign research, allowing to exclude or confirm the growth of pituitary microadenomas.
In addition to determining the concentration of adrenal hormones, thyroid, sex steroids, the patient will be offered an MRI or CT scan. Radiography is not of great importance when microadenoma, since the tumor does not change bone structure, and computer or magnetic-resonant tomography is able to give a full picture of the disease, «showing» the layered structure of the pituitary gland.
It should be noted that at very small sizes of tumor, even modern research methods can be ineffective however, the clinic at hormoneproducing microadenomas makes to confirm a diagnosis in other ways. To help the doctor come studies of pituitary hormones (radioimmunoassay method), the increase is not in doubt in the presence of the tumor.
Treatment of microadenomas should begin as soon as will be exposed to an accurate diagnosis. Asymptomatic microadenomas do not require specific therapy, but observation in such cases, be sure not to miss the beginning of the further growth of education. The patient is recommended once a year or two to undergo MRI and regular visit to the endocrinologist, and if you develop symptoms of tumor growth, then a visit to the doctor should not be postponed.
Treatment of pituitary microadenomas is required in the case of hormonal activity, or continued growth. For best results, usually combining different types of treatment depending on the type of tumor.
Therapy microadenomas include:
- The appointment of agents, stabilizing hormones;
- Surgical removal;
- Radiosurgery of the tumor.
Conservative therapy is determined by the nature of microadenomas hormones and the ability of tumors to respond to drug exposure. A particularly good effect is observed in prolactinomas when the appointment of cabergoline, parlodel (dofaminomimetiki) is able within two years to lead to the complete disappearance of the lesion and cessation of excessive synthesis of prolactin. In some patients there is a good result in the appointment of somatostatin and its analogues (octreotide) and thyreostatics, but in the case of such microadenoma drug therapy does not always give a lasting effect, so can be a precursor to surgical removal of the tumor.
Shown surgical tactics in relation to microadenoma that are not amenable to conservative treatment or there is further growth. The need for open surgery (craniotomy) for small tumors of the pituitary usually does not occur, and the surgeon uses the endoscopic technique where the tumor is removed with the help of an endoscope through the nasal passage. Maloinvazivnogo such an operation allows to avoid serious complications, and involves a short postoperative period of hospitalization of not more than three days.
The growing popularity and radiosurgery, allowing to remove the tumor without surgery. Radio knife is a radiation beam, acting purposefully microadenomas. The accuracy of radiation exposure is achieved by CT or MRI. Radiosurgical removal of the tumor may be performed on an outpatient basis. After exposure there is a gradual reduction in the size of microadenomas that does not cause the patient any discomfort, but if the tumor produces hormones, the parallel can be assigned to medication to correct hormonal background.
The prognosis for microadenoma usually good, because the tumor of small size is better treatable than a large tumor, compressing the neighboring structures. If the doctor deems the surgery the only possible treatment of the disease, you should not be afraid to refuse because the risk of progression from microadenomas in the absence of treatment are much higher than with surgical removal, especially since the latter is usually conducted by minimally invasive method. Patients with asymptomatic microadenomas no need to change lifestyle or to take any drugs, but about regular doctor’s visit and MRI monitoring should not be forgotten.