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Follicular thyroid cancer.
Last reviewed: 05.07.2025

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As modern statistics show, thyroid cancer accounts for up to two percent of all cancer cases worldwide. In this article, we will try to learn as much as possible about the pathology that ranks second in terms of the frequency of malignant manifestations diagnosed in this area of the human body. We are talking about a disease called follicular thyroid cancer.
Causes of Follicular Thyroid Cancer
Approximately 15% of all cases of determining a malignant neoplasm localized in the area of the human body considered in this article are follicular tumors. But in order to conduct therapy as effectively as possible, it is necessary to obtain the most accurate picture of pathological changes and identify the source of the "failure".
The causes of follicular thyroid cancer have not yet been determined. However, doctors believe that the following play a certain role in its development:
- Iodine deficiency in the patient's body.
- A decline in a person’s immune status and the inability of his body to resist negative influences.
- Exposure to ionizing radiation. It can be both external and internal (for example, the introduction of radioactive iodine into the treatment protocol). The point is that this element has the property of accumulating in the thyroid gland, subsequently provoking the development of cancer. A child can be exposed to such influence even in utero. In an adult, the probability of provoking a failure and the development of a neoplasm in such a situation is lower, since a higher dose of radiation is required.
- The hereditary factor cannot be ruled out.
- As experts have established, the precursors of the disease in question were often benign neoplasms.
- Prolonged exposure of the head and neck area to X-rays, which causes the cells in this area to mutate.
- Although the pathology in question has been diagnosed in very young children, the majority of patients are over forty years of age.
- There are a number of specialties that fall into the list of the most dangerous in light of the problem under consideration.
- Doctors suggest that the cause of follicular thyroid cancer may also be prolonged stress in which the patient's body is. Stress leads to a decrease in the body's defenses, which "opens the way" to various pathologies.
- Having bad habits only worsens the situation, making the risk of developing a tumor significantly higher. Carcinogens found in tobacco and alcohol have a detrimental effect on a person's immune status, reducing resistance to the appearance of atypical cells.
- Multinodular goiter.
But the sources listed above, and far from a complete list, are only the assumptions of doctors about the etiology of the disease. Symptoms of follicular thyroid cancer
This pathology is more often observed in people over forty years of age, but children are not immune from it either. Although the percentage of such patients is quite small, the trends of the lesion are alarming.
The pathology in question is characterized by a low rate of progression, so the symptoms of follicular thyroid cancer begin to appear quite late:
- Nodular formations gradually appear on the front side of the neck.
- Rarely, but still, it is possible to observe an increase in the size parameters of the lymph nodes.
- A person begins to feel an obstacle when swallowing.
- Difficulty inhaling and exhaling occurs.
- Chronic fatigue is observed.
- Pain gradually develops in the affected area.
- These metamorphoses lead to a breaking of the voice.
- Problems with sleep appear.
- Tingling in the limbs and cramps may occur.
- The production of viscous mucus is produced.
- Hyperthyroidism develops.
- The person becomes apathetic.
- Increased sweating is observed.
- Decreased appetite, leading to weight loss.
- Metastasis begins to be recognized at a later stage of the disease.
Follicular Thyroid Cancer TNM Stages
The International Association of Doctors has adopted a cancer ranking system that divides the clinical picture of the disease and the severity of the symptoms into different levels of pathology. The stages of follicular thyroid cancer tnm are made up of three main parameters: T (Latin tumor), N (Latin nodus) and M (Latin metastasis). It is the condition, as well as the presence or absence of deviations in these elements, that forms the stages of disease progression.
Tumor size:
- T0 – neoplasm is not detected.
- T1 – the neoplasm is less than 2 cm in size. In some cases, a more detailed division is carried out: T1a – size parameters up to one centimeter and T1b – from one to two centimeters.
- T2 – the neoplasm is larger than 2 cm, but does not exceed the parameters of 4 cm.
- T3 – the tumor size is more than 4 cm. The neoplasm does not extend beyond the thyroid gland. Also, this category includes any neoplasm that has a minimum presence beyond the capsule.
- T4 – this category is divided into:
- T4a – a formation of any size, with penetration into surrounding tissues: laryngeal nerve, trachea, esophagus, larynx, other tissues.
- T4b – a formation invading the carotid artery, the fascia of the prevertebral region, and the vessels of the retrosternal region.
It is worth noting that if the carcinoma remains undifferentiated, it is automatically assigned stage T4, regardless of its size parameters.
Presence of metastases in adjacent lymph nodes:
- NX - lack of ability to determine metastases.
- N0 - no invasion.
- N1 - there is local metastasis:
- N1a – invasion detected in the VI zone of lymphatic drainage.
- N1b – invasion differentiates into cervical or retrosternal lymph nodes. In this case, both unilateral invasion and bilateral lesions may be observed.
Detection of metastases in more distant areas of the body:
- MX – there is no way to assess the presence of such an invasion.
- M0 – such invasion is absent.
- M1 – such an invasion is diagnosed.
Having determined the above, the oncologist can classify the pathological picture under consideration into one of four stages:
- The first is a neoplasm up to 2 cm in size, no metastases, and non-specific cells are not subject to decay. The most favorable stage of cancer in terms of prognosis.
- The second is the size of the neoplasm from 2 to 4 cm (the tumor does not cross the capsule border), there are no metastases.
- The third is a neoplasm larger than 4 cm, extending beyond the capsule (without metastases), or a tumor of any size with local metastases to adjacent cervical lymph nodes. Without decay and invasion into more distant organs.
- The fourth A is a neoplasm of any size, but the presence of invasion beyond the capsule, differentiated metastases in the cervical and/or thoracic lymph nodes. But no damage to other organs is observed.
- The fourth B is a neoplasm of any size, the presence of invasion beyond the capsule with growth in the direction of the cervical spine and adjacent large blood vessels and lymph nodes. Metastasis to other organs is not observed.
- The fourth C-invasion shows a wide scale of damage, affecting other organs. The most severe prognosis for the development of the pathology in question.
Based on the TNM system, the stage of the disease is determined, which allows for an assessment of the prognosis for its management.
Follicular thyroid cancer stage 1
Normally, the tissues of the gland in question consist of structural components of a spherical configuration, called follicles. If a malignant neoplasm also includes follicles, this disease is called follicular cancer.
Stage 1 follicular thyroid cancer is characterized by low iodine levels in the patient's body. In this case, there is an acute deficiency of this element. The tumor shows "moderate aggressiveness". The prognosis for its diagnosis is generally favorable. But this result is achieved somewhat more difficultly than with the papillary type of pathology. In this case, the affected gland is completely removed.
The first stage of the disease manifests itself in small nodules of neoplasms. After their size increases, the symptoms of the disease begin to gradually manifest. At the same time, the intensity of symptoms increases slowly. This may take more than one year. Metastases are completely absent.
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Follicular thyroid cancer stage 2
Each type of malignant thyroid disease has its own individual characteristics. Stage 2 follicular thyroid cancer is caused by the appearance of metastases. At the same time, the size parameters of the neoplasm and the condition of the nearby lymph nodes do not play any significant influence in determining the degree of the disease.
Follicular thyroid cancer stage 3
When the patient's condition worsens, the disease moves to the next stage of pathological manifestations. Stage 3 follicular thyroid cancer has the following characteristics:
- Tumor size characteristics can be of any size.
- The neoplasm is not limited by the boundaries of the capsule, but extends beyond it.
- The sizes of nearby lymph nodes are normal.
- Regional metastasis is diagnosed.
- There is no distant invasion.
But another option is also possible, when there are no metastases, but the lymph nodes are significantly enlarged.
But the most unfavorable in prognosis is the fourth stage, which indicates lost time and late terms in diagnosis. This stage is stated when the scale of metastasis covers quite large areas, affecting distant organs. At the same time, the size of the tumor itself is no longer important.
Follicular papillary thyroid cancer
In their practice, oncologists, based on the results of histological examination, divide the pathology of the nature in question into:
- Papillary adenocarcinoma, which is characterized by a slow rate of progression with possible limited regional metastasis.
- Follicular adenocarcinoma, which also has a slow rate of development.
- Follicular papillary thyroid cancer is a highly differentiated type of oncological disease. This category of diseases is more common (up to 80% of all thyroid cancer cases) than the next two. At the same time, they show good susceptibility to arresting therapy.
- Medullary carcinoma is rarely diagnosed and is thought to be hereditary.
- Anaplastic (undifferentiated) category of tumors – low percentage of diagnosis. Characterized by high rate of progression. The highest percentage of fatal outcomes.
The follicular type of development has a more aggressive course compared to papillary carcinoma. The papillary type of cancer is diagnosed more often, especially in children and patients of pre-retirement and retirement age.
Metastasis of lymph nodes in papillary carcinoma is noted much more often than in other cases. Whereas follicular carcinoma is characterized by a higher probability of tumor growth into vascular components. The prognosis for mortality directly depends on the degree of invasion.
Follicular carcinoma is characterized by damage to nearby tissues and distant organs of the human body. These can be lungs, bone tissue, epidermis, brain and others.
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Poorly differentiated follicular thyroid cancer
In addition to the follicular and papillary malignant types of the pathology in question, which are related to the highly differentiated course of the disease, oncologists diagnose cellular-follicular low-differentiated thyroid cancer.
Cases of its determination are quite rare. The frequency of this form of the disease does not exceed 4-7% of all malignant tumors of the thyroid gland.
This type of pathology is characterized by a high rate of progression. The patient begins to complain about the acceleration of growth of neoplasms, which are already visible to the naked eye. He begins to have problems with swallowing and breathing. Gradually, the voice changes.
Already after two to four months from the onset of the disease, a person begins to feel pathological symptoms and seeks advice from a qualified specialist.
When visually examining the facial area of the neck, one can observe the asymmetry of its shape. When palpating, the outline of the formation is dense, not clear and blurred. When pressing, the patient feels increasing pain.
Low-differentiated types of malignant thyroid tumors include medullary carcinoma and anaplastic tumor.
The prognosis for this type of disease is significantly worse than in the case of highly differentiated cancer, since the rate of progression is so high that after diagnosis, oncologists sometimes give the patient only a few months, or even weeks, to live.
Diagnosis of follicular thyroid cancer
If a person develops negative symptoms or a deviation from the norm in health is detected during a routine preventive examination, the patient is referred to a specialized oncological institution, where an oncologist will prescribe a general package of measures necessary for a complete examination of the patient's health.
Basically, the diagnosis of follicular thyroid cancer includes:
- Consultation with an otolaryngologist and an oncologist, with their examination of the patient and screening of his medical history.
- Ultrasound examination allows visualization of the area of interest, which makes it possible, without causing particular harm to the human body, to identify neoplasm nodules that were not detected by palpation.
- X-ray computed tomography is a method that does not violate the integrity of tissues and allows for a layer-by-layer study of the internal structure of the thyroid gland.
- Magnetic resonance imaging is a medical examination method that allows obtaining images of the organ being examined in 3D and a number of X-ray images. By recording this information on the computer's hard drive, the examination information can be used more than once, throughout the entire period of examination and treatment of the patient.
- Taking a targeted puncture biopsy of a tumor to determine its benign or malignant nature. After receiving the material, a histological and immunochemical study is performed. This method gives the oncologist an answer to the question of the need for surgical intervention.
- Radioisotope examination will allow to determine isotope nodes, manifested as a defect of their accumulation. But this is given that the tumor is diagnosed. It will not be possible to differentiate its nature (benign or malignant) using this method. This method is very effective in the plane of establishing the presence of metastases, their scale and localization. But this fact is justified only if the modified cells have the ability to accumulate iodine-containing chemical compounds, as well as in the absence of tissue cells of the thyroid gland, which was excised earlier.
- A wide range of various biochemical studies is carried out. The result of the analysis is obtaining a quantitative indicator of the level of a particular hormone that participates in the normalization of the thyroid gland. The level of TSH, T3, T4 hormones is determined.
- Laryngoscopy is an examination of the larynx, including the vocal cords, performed with the introduction of a rigid laryngoscope. The procedure is performed under general anesthesia during surgery.
Modern medicine is equipped with a sufficient number of different diagnostic methods that allow pathology to be recognized at an early stage of its development, which significantly facilitates the work of the oncologist and preserves the health of the patient.
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Treatment of follicular thyroid cancer
The protocol for treating this type of pathology remains quite controversial today. A number of oncologists are quite sure that if the neoplasm is small in size and there are no metastases (which is mostly the case), then it is quite sufficient to simply excise the affected lobe of the gland together with the neoplasm and isthmus tissues. This intervention shows good results, leading to complete recovery. This statement is based on the fact that the percentage of relapses of the disease in question is quite low.
But they also have opponents who claim that treatment of follicular thyroid cancer should be carried out on the basis of subtotal or total thyroidectomy, which means complete removal of the thyroid gland. Thyroidectomy is a fairly radical method of eliminating the problem.
Today, the typical treatment protocol for the disease in question looks something like this (follicular carcinoma is well-limited, small in size, without metastasis):
- A surgical oncologist performs a hemithyroidectomy (an organ-preserving operation - surgical removal of one lobe of the thyroid gland with the isthmus) or a thyroidectomy (complete excision of the thyroid gland together with pathological neoplasms).
- In the postoperative period, the patient begins to receive radioactive iodine (50-150 mCi I-131). If a relapse of the disease is observed, the radiation dosage is increased. There are several types of radioactive iodine, but there is only one that causes cellular toxicity. Modified cells absorb this chemical element well, which provokes their destruction by the radioisotope iodine-131.
- In parallel with this, the patient begins to receive drugs related to thyroid hormonal drugs. The pharmacodynamic characteristics of these drugs allow suppressing the secretion of TSH and suppressing the remaining mutated cells individually. For this purpose, antistrumin - darnitsa, bagotirox and thyreokomb are actively used.
Thyreokomb tablets are administered orally, half an hour before the morning meal. The drug must be swallowed completely, without crushing, together with the required amount of liquid. The drug is administered once a day.
The daily dosage of the drug is prescribed to the patient by the attending physician individually. This parameter is based on the analysis of the clinical picture of the pathology and the results of laboratory tests. Mostly, the starting daily dose is prescribed in the amount of half a tablet.
If the required therapeutic effectiveness is not observed, the attending physician gradually increases the dose, bringing it to one or two tablets. The dosage increase is carried out after one or two weeks of administration.
If the patient has a history of cardiovascular pathology, a tendency to epileptic seizures, or adrenal cortex insufficiency, then the adaptation period for the next dose increase is extended and can last from four to six weeks, or even more.
The medication should be taken continuously, without interruptions. The duration of the course of treatment is determined by the attending physician. Patients are not recommended to independently adjust the dosage or schedule of administration of the drug in question.
Contraindications to the use of Thyrocomb in the treatment protocol for follicular thyroid cancer include increased individual sensitivity to one or more components of the composition, herpetiform dermatitis, acute myocarditis, thyrotoxicosis, uncontrolled adrenal cortex insufficiency, severe angina, acute myocardial infarction. There are also a number of diseases that require more careful administration of thyroid hormone.
After the postoperative recovery period has passed, such a patient remains under the supervision of specialists for the rest of his life and must undergo periodic examination, which includes a study that determines the level of hormones (including thyroglobulin). A high level of this hormone (more than 10 ng / ml) in the postoperative period may indicate a relapse of the disease.
Prevention of follicular thyroid cancer
It is usually possible to reduce the risk of developing a particular disease by following a number of simple rules and recommendations from an oncologist. Prevention of follicular thyroid cancer is based on a healthy lifestyle.
The specialist's recommendations include:
- Giving up bad habits: smoking, alcohol, drugs...
- Maintaining your weight within acceptable limits.
- Reconsider your attitude to food. Minimize the consumption of fatty foods, fast food dishes and supermarket products laden with a large number of "E": various stabilizers, emulsifiers, colorings, flavor enhancers, etc. The daily diet should be balanced and rich in vitamins and minerals. Particular emphasis in this situation is placed on iodine-containing products.
- To maintain the level of vitamins and minerals, including iodine, at normal levels, you can also use pharmacological drugs, regularly taking them in courses.
- It is worth avoiding prolonged exposure of open areas of skin, and the whole body, to direct sunlight. You should not get carried away with frequent visits to the solarium.
- It is necessary to protect yourself from radiation. This is especially true when buying a house or apartment. It is worth choosing a more environmentally friendly place.
- Regular consultations with specialized doctors are necessary. If the patient has already had cancer, he/she should undergo an annual X-ray examination and tests to monitor the level of hormones in the blood.
Prognosis of Follicular Thyroid Cancer
When visiting a specialist, the patient, after the diagnosis is established, is interested in his chances of recovery. The prognosis for follicular thyroid cancer is, in most cases, quite favorable. But it still largely depends on the stage of cancer development at which the disease was diagnosed and treatment of the problem began.
The scant medical statistics show that the five-year survival rate of patients who have undergone the necessary treatment shows:
- When diagnosed at the first stage of the disease, the survival rate is 100%.
- In case of stage II follicular thyroid cancer - 100% survival rate.
- At the third stage of malignant neoplasm – 71% five-year survival.
- At the fourth stage of the pathology, the five-year survival rate is 50%.
As sad as it may sound, but in recent years the number of patients with oncological diseases has been growing, affecting all layers and age categories of human society. Upon hearing the diagnosis - follicular thyroid cancer, almost all patients, at first, fall into a stupor, perceiving the diagnosis as a death sentence. But this is far from true. If the patient is "lucky" and the malignant tumor is detected at an early stage of its development, then, with effective treatment, the patient can subsequently return to his usual way of life (of course, with some regard to the disease and the possibility of relapse). But it is still within human power to reduce the risk of such a pathology, and the key to this is a healthy lifestyle, which is able to "protect" the body from many diverse health problems, including reducing the likelihood of both benign and malignant tumors. Therefore, take care of yourself and be healthy!