Table of contents:

1. Causes of thyroid cancer
2. What symptoms of thyroid cancer can there be?
3. Types of thyroid cancer
4. Diagnosis of thyroid cancer
5. Treatment of thyroid cancer
6. What is the prognosis of thyroid cancer patients?

The most well-known thyroid diseases are probably hyperthyroidism and hypothyroidism. However, among the conditions that may be associated with this organ, there are also many other entities, such as thyroid cancer, among others. Fortunately, malignant thyroid tumours do not occur with great frequency - it is estimated that thyroid cancer is diagnosed in about 1500-2000 patients per year in Poland.

Thyroid cancer can occur in a person of any age, but typically occurs in patients over 40 years of age. The disease is far more common in women

Causes of thyroid cancer

There are several different factors that are associated with the occurrence of thyroid cancer. Genetic factors seem to play an important role, as it is noticeable that if someone in a patient's family has a history of thyroid cancer, then the risk of them developing the disease is significantly increased. It should also be noted that one type of thyroid cancer, medullary thyroid cancer, can have up to a quarter of all cases that are hereditary.

Another factor that may be significant in the pathogenesis of thyroid cancer is exposure to ionising radiation, which may result, for example, from a history of radiotherapy in the head or neck region.

What could be the symptoms of thyroid cancer?

It is not uncommon for thyroid cancer to lead to no symptoms at all. Other patients, however, struggle with quite troublesome symptoms of thy roid cancer - these can be:

• the presence of a nodule within the thyroid gland (the majority of thyroid nodules, however, are of a benign nature - the fact that the nodule is hard, non-painful and non-movable may suggest that the lesion is malignant; in addition, fast enlargement of its size and irregularity of the nodule's edges should also arouse vigilance),
• enlargement of the neck circumference,
• neck pain,
• enlargement of the lymph nodes in the neck (usually these become hard),
• persistent hoarseness,
• problems with swallowing or breathing.

Types of thyroid cancer

Malignant tumours of the thyroid gland are of several types. These are:

• papillary thyroid carcinoma: the most common malignant neoplasm of the thyroid gland, originating from its follicular cells, it typically develops in people between 30-50 years of age, it spreads mainly through the lymphatic vessels, so if papillary carcinoma gives metastases, these are usually in the lymph nodes,
• follicular thyroid carcinoma: a lesion that also originates from the follicular cells of the thyroid gland, usually this thyroid carcinoma appears after the age of 50, it spreads through the path of blood vessels, so that metastases of follicular thyroid carcinoma can appear in many different organs,
• medullary thyroid carcinoma: a malignant neoplasm that develops from the C cells of the thyroid gland (these cells are responsible for the production of calcitonin, so elevated levels of this hormone in the blood are possible with this tumour),
• anaplastic thyroid carcinoma: a rare tumour that is characterised by its rapid growth and the fact that it is very difficult to treat, usually appearing in people over 60 years of age,
• lymphoma of the thyroid gland: a malignant tumour of the thyroid gland found mainly in the elderly, characterised by the fact that it increases in size quite rapidly.

Thyroid cancer, photo: panthermedia

Diagnosis of thyroid cancer

If thyroid cancer is suspected, it is important for the patient to undergo a Medical US examination of the thyroid gland. During Medical US, it is possible to visualise, among other things, a thyroid nodule - the size of the nodule, the regularity of the margins of the lesion and the blood supply of the lesion are then determined. However, Medical ultrasound of the thyroid alone cannot determine whether a patient's thyroid lesion is benign or malignant. For this, a biopsy of the lesion and subsequent histopathological examination is necessary. Medullary, papillary and anaplastic thyroid cancer can be diagnosed by this route. An exception is follicular thyroid carcinoma, in which case histopathological examination may indicate that the patient may have this disease, although a definitive diagnosis of this type of thyroid carcinoma can only be made after the entire lesion has been resected and assessed by histopathological examination.

Patients may wonder whether there are any laboratory tests - e.g. any tumour markers - that can indicate thyroid cancer. Generally, there are none - only in the case of medullary carcinoma may there be an increase in calcitonin levels.

Treatment of thyroid cancer

The primary treatment for thyroid cancer is surgical removal of the lesion. Usually, the entire thyroid gland is removed from the patient along with the cancer focus, but sometimes the decision is made to remove only part of the thyroid gland (e.g. one lobe). In addition to surgical treatment, radioactive iodine treatment, which is carried out after surgery, is of great importance for the most common malignant thy roid tumours - i.e. papillary and follicular carcinomas. This therapy is generally considered safe and can be supplemented with radioactive iodine treatment of thyroid cancer in principle in most patients - iodine is not used in pregnant or breastfeeding women. In addition to these, radiotherapy and chemotherapy are sometimes - but far less frequently - used in the treatment of thy roid cancer.

It is also worth mentioning here what is necessary after surgery. In patients who have had their thyroid gland removed, levothyroxine treatment is implemented. Firstly, it is aimed at supplying the body with the thyroid hormones it needs. Secondly, the levothyroxine dose is set so that the patient has a slight excess of thyroid hormones - this leads to a decrease in pituitary thyrotropin (TSH) levels. This phenomenon is expected on the grounds that TSH may be associated with metastasis of thyroid cancer.

What is the prognosis of thyroid cancer patients?

The prognosis of patients with thyroid cancer depends on the specific type of disease they develop. However, in most cases of this disease, the prognosis is very good - with appropriate treatment for both papillary, follicular and medullary cancer, the 10-year survival rate is as high as 90%. The prognosis for anaplastic carcinoma is much worse - it is unfortunately characterised by a rather rapid growth rate and, even despite the implementation of optimal treatment within just a few months, this thyroid cancer can lead to the death of the patient.