Adenoma thyroid, follicular tumor, toxic
Thyroid adenoma is a common phenomenon found in women of Mature age. Among patients with a similar diagnosis of the fairer sex several times more than men and the average age is 45-55 years of age. This is a benign process, which, however, can be a source of cancer.
Adenoma is a nodular rounded education, built from dividing cells of the gland itself which distinguishes it from other benign changes (colloid cyst, in particular). About three quarters of all detectable in the thyroid gland nodal formations are adenomas, some of them can produce hormones significantly changing the health and life of patients.
Thyroid gland (TG) is a small organ located on the front of the neck and consisting of the left and right lobe connected by an isthmus. Without looking at its small size, this iron is able for violation of incapacitate many other organs because it produces a very important for the normal functioning of hormones.
Microscopically the thyroid parenchyma is represented by the follicles (microscopic cavities), filled with the substance (colloid), in which there is an accumulation of the hormones thyroxine and triiodothyronine. For their synthesis, the body needs iodine, therefore its level in food and the environment can have a direct effect on the gland, and the lack – cause serious pathology.
Main effects of thyroid hormones are considered as acceleration of metabolism and catabolism (decomposition) of nutrients with the release of energy, regulation of blood sugar, rhythm of heart contractions, nerve function, etc. in short, these hormones can change the metabolism as a whole, but because their excess or inadequate education cannot pass unnoticed.
Part of the cells of the thyroid parenchyma is involved in the regulation of calcium metabolism (C-cells), others synthesize biologically active substances, whose role is not fully elucidated (cells Hurtle).
Production of hormones by the thyroid gland occurs spontaneously, this process is coordinated by the pituitary gland at the base of the brain. The anterior pituitary secretes thyroid stimulating hormone (TSH), which enhances the secretory activity of the thyroid gland. In the case of increasing the concentration of thyroxine and triiodothyronine activates the feedback mechanism, inhibiting the formation of thyrotropin. Such a mechanism is needed to control hormone levels, excess of which, as a drawback, significantly alters the operation of almost all systems and organs.
In cases where in the thyroid tumors appear capable of synthesis of hormones, a complex mechanism of its interaction with the pituitary is broken and there are symptoms of hyperthyroidism. Such a phenomenon is possible when adenomas, certain types of which are always accompanied by excessive production of hormones.
Benign glandular tumor – adenoma – is a single or multiple, round or oval, but always with clear contours and thick capsule. The contents of this adenoma, the nature of the cells from which it is formed, determine its species. Adenoma is also found in the gland where you already have a goiter.
It should be noted that the nodes in the thyroid by the age of 50 can detect almost every second woman, however, not all of them directly attributed to adenomas, because such a diagnosis is competent only after histological examination of the tissue site. Dilated follicles, filled with colloid (colloid nodes, or cysts) are not considered to be adenomas, and therefore do not require such careful attention, as a tumor that is able to grow and function, and under certain conditions, has malignant potential, that is, it can become a cancer.
Causes and types of adenomas of the thyroid gland
Factors contributing to the growth of the adenoma, and its exact causes, so still not established, but the known conditions under which the probability of a tumor is high:
- Hyperfunction of the pituitary gland when excessive stimulation of the thyroid gland thyroid-stimulating hormone causes the reproduction of her cells with the formation of the tumor.
- The disruption of the sympathetic nervous system.
- The effects of toxins and occupational hazards, adverse external environmental conditions, in particular, the deficit of iodine in water and soil, as evidenced by the frequent appearance of the adenoma on the background of non-performing node or goiter.
- Genetic predisposition and genetic abnormalities, and autoimmune disease.
- The presence of a goiter.
- Injuries to the neck area in violation of the integrity of the capsule of the thyroid gland that can be triggered to develop an autoimmune response to follicular epithelium with its excessive proliferation.
Most often adenoma over many years, flows without violations of hormonal background, providing only a local effect due to the increase in size, but approximately every tenth of a tumor can be transformed into a functioning toxic adenoma. With increasing size of such a node increases the level of hormones produced by the cells, then the pituitary, in response, reduces the production of thyroid-stimulating hormone, respectively, the rest of the cancer tissue stops working in «normal» mode and atrophy, but its place is gormonalnaguye tumor. In this phase the growth of tumors in the body emitted an increased amount of thyroid hormones, and thyrotoxicosis develops.
Types of adenoma determined by its histological features. Release:
Follicular adenoma is the fifth part of all benign glandular tumors and looks like tightly-elastic node, mobile, well demarcated from the surrounding tissue. Microscopically it consists of large or small follicles, for which it received its name, however, the embryonic kind is devoid of cavities.
Papillary adenoma has the form of a cavity (cyst), within which are found papillary proliferation of the epithelium. Adenoma of the b-cells (Hurthle) contains no follicles or papillae, and is composed of large b cells. She’s quite aggressive and in a third of cases may be malignant.
Toxic adenoma is considered to be the morphological basis of the disease Plummer when there is an overproduction of thyroid hormones with the development of hyperthyroidism. This form of tumor is the most striking clinical picture.
Symptoms of thyroid adenoma
In most cases, the adenoma does not cause any significant disturbances in the body, so the symptoms are scarce. The only exception is toxic adenoma develops when the Plummer syndrome with distinct clinical signs of hyperthyroidism.
Symptoms inactive benign tumors:
- The presence in the gland of a dense or an elastic host, movable and painless at a palpation. Often, such nodes are detected by chance on ultrasound or when you visit the endocrinologist.
- The growth of the adenoma are possible:
- deformation of the neck;
- discomfort when swallowing;
- pressure in the neck;
- shortness of breath, cough;
- painful sensation at the site of localization of the adenoma of large size.
Large adenoma becomes visible to the naked eye and is easily detectable.
Symptoms of toxic adenoma more diverse, arise from overproduction of thyroid hormones, this interferes with basal metabolism, cardiovascular and nervous systems, gastrointestinal tract, etc.
In the initial stages of development of the adenoma, the patient becomes irritable, loses weight, does not tolerate heat, prone to sweating, tires easily, especially when exercising. Often patients complain of unexplained increased heart rate, pain in the heart, arterial pressure jumps.
With the further growth of the tumor there is a vivid picture of hyperthyroidism. Patients irritable, tearful, poor cope with their emotions, complain of violations of the heart, intestines, frequent fever, and exophthalmos (exophthalmia). In males reduced potency, in women likely infertility and pathology of the menstrual cycle.
If the spasms and disturbance of motility of the stomach or intestines be more to subjective discomfort, the pathology of the cardiovascular system caused by the toxic effect on the myocardium of thyroid hormones, is a much more dangerous phenomenon, which can be the cause of serious complications and even death of the patient.
Disorders of the heart manifest tachycardia, atrial fibrillation, angina (pain). Thyroid hormones have a toxic effect on the myocardium and conductive system of the heart that runs literally for wear because of what its functionalities are being rapidly depleted, the myocardium is weakened, and the conditions for the development of heart failure. Patients experience weakness, low resistance to even minor physical stress, edema stagnant, severe shortness of breath. Perhaps the development of such dangerous complications such as pulmonary edema, requiring emergency care.
Diagnosis adenomas of the thyroid gland
Since tumor masses of the thyroid gland often does not manifest itself, they may be detected accidentally, during a routine ultrasound examination or when you visit the endocrinologist in connection with another disease. In toxic adenoma diagnosis is established after examination of the patient and a conversation with him about the nature of symptoms.
When inspecting the neck of the patient may be noticeable deformation or the presence of a tumor node. Palpation gives information only about its size, density, mobility, but an accurate diagnosis so it is impossible to set, so the patient is sent for additional laboratory and instrumental examinations.
The most affordable method of diagnosis of tumors of the thyroid gland is an ultrasound study that requires no special training and can be performed by almost everyone. At the ultrasound the physician can determine the location, form of unit, the size and the nature of blood flow in the Doppler mode, however, to reliably distinguish cancer from adenomas or colloid of a node is not always possible.
If ultrasound does not give information about the location and basic characteristics of the tumors, it is possible to use MRI or CT, although the latter is accompanied by irradiation, so it is better to avoid its use for the study of the thyroid gland.
Radioisotope scanning using radioactive iodine allows you to set the functional activity of tumor masses and tissues of the gland. Toxic adenomas tend to accumulate a significant amount of iodine, whereas inactive tumors and colloid nodes such features do not show.
A blood test for hormones shows increased concentrations of thyroxine and triiodothyronine and a decrease in thyroid-stimulating hormone in the presence of toxic adenomas. In other cases, their levels will remain within the normal range.
In the biochemical study of the possible detection of signs of impaired fat and carbohydrate metabolism: a decrease in lipids and tendency to increase blood sugar levels.
The next stage of refinement or confirmation of the diagnosis becomes a needle biopsy, the information content of which is about 80%. The objective of this study is the confirmation or refutation of the malignant nature of the tumor and the enlarged set is not always possible. That is, the biopsy can only determine there is a cancer patient or not whether you need surgery or limited supervision.
In order to determine the type of adenoma, it is necessary to study fragment formation with the capsule, which can be achieved when puncture with a fine needle. Also if you puncture it is impossible to distinguish a follicular adenoma from follicular cancer, a reliable sign of which is the invasion of the follicular tissue to the capsule, therefore, for accurate diagnosis requires the removal of the entire node with histological examination of the obtained material.
Treatment of thyroid adenoma
Upon confirmation of the diagnosis of the adenoma the doctor will have to solve the main problem: required operation to remove the tumor or can be limited to conservative methods of treatment and observation.
Conservative therapy is indicated during pregnancy, a serious condition of the patient, older age, concomitant diseases, making surgical removal of the tumor threat. When colloidal node, you can do no operations and limited supervision, while in thyrotoxic adenoma conservative treatment serves only as a preparatory stage before the mandatory removal of a tumor node.
Thyrotoxicosis drugs reduce the production of hormones by tissues of adenoma, thus achieved the euthyroid state, when the concentration of hormones getting back to normal. Treatment of such drugs definitely assigned before surgery to remove the toxic adenoma.
Conservative treatment includes radioiodtherapy in which radioactive iodine accumulates in the cells of the prostate and destroys them. In some cases, practiced the introduction in the tumor site of ethanol which causes cell damage, necrosis and scarring of the tumor.
Surgical treatment allows you to completely get rid of the tumor, and in the case of Plummer disease is the only way. A node, the absence of signs of malignancy in the cells of the adenoma and disease in the surrounding parenchyma, can be limited to removing only the tumors (enucleation of the node). If the adenoma is large or has signs of malignant growth, the volume of transactions expands, and it is necessary to delete half of most or all of the gland. Such interventions involve a risk of bleeding, damage to the parathyroid glands that regulates the metabolism of calcium, laryngeal nerve that can cause problems with voice.
After successful treatment of thyroid adenoma, the patient must once a year visit to endocrinologist and to comply with its recommendations. Usually, doctors advise to avoid stress, is not under the open sun, to abandon the Solarium, to comply with diet and rest. If the patient has lost all of the thyroid gland, the endocrinologist will prescribe replacement hormone therapy.
The prognosis for benign thyroid tumors is quite good, but provided that treatment is initiated as early as possible. Pronounced hyperthyroidism can lead to irreversible and dangerous changes in other organs, so a visit to the endocrinologist with the appearance of the above-described complaints, it is better not to postpone. It should also be remembered and the risk of malignancy even quite benign tumors, therefore, constant supervision by an endocrinologist is a prerequisite with this diagnosis.