A large proportion of the population suffers from thyroid disease. However, thyroid cancer is quite rare and in many cases is only discovered by chance. According to research, around 7,000 people are diagnosed with thyroid cancer each year, while approximately 72,000 women are affected by breast cancer alone each year.
What is thyroid cancer?
Thyroid cancer often occurs in women and, after the first signs of suspicion, requires not only a comprehensive ultrasound examination but also a fine-needle biopsy, in which a sample of the thyroid carcinoma is taken and then examined under the microscope. Thyroid cancer can occur in any area of the thyroid gland.
The respective tissue type as well as the location where the carcinoma has settled provide the responsible examining pathologist with information about the form of the carcinoma and is an important building block for the further therapy of the tumour.
What types of thyroid cancer are most commonly diagnosed?
Papillary thyroid carcinoma
The most common type of thyroid cancer, diagnosed in about 60% of all cases that occur, especially in women. In this type, the cancer cells usually spread via lymphogenic metastasis and in many cases also affect the nearby lymph nodes in the neck.
Follicular thyroid carcinoma
The second most common form of thyroid carcinoma, this type is found in about 30 % of all cases. The dangerous metastases in this form of thyroid cancer spread mainly through the bloodstream to the lungs or brain.
Medullary thyroid cancer
A rarer form of thyroid cancer that is diagnosed in only about 5% of all cases. The disease occurs mainly in the tissue of the C-cells, which are responsible for the production of calcitonin and thus ensure stable regulation of the phosphate and calcium balance in the body. The formation of the carcinoma reduces the calcium content in the blood.
Anaplastic thyroid carcinoma
The rarest and most dangerous type of thyroid cancer, affecting 1% of people. The disease progresses very quickly and is hardly curable.
What are the causes of thyroid carcinoma?
Research into the causes of thyroid cancer is still somewhat in the dark. Clear explanations for the disease are still not to be found in medical circles.
While other known thyroid diseases are mostly due to an acute iodine deficiency or a congenital malfunction of the thyroid gland, scientists assume that the development of papillary and follicular thyroid carcinoma is triggered by radioactive radiation.
The development of modullary thyroid carcinoma is mainly due to a genetic defect of the 11th chromosome, which is often responsible for the formation of this form of thyroid cancer.
In such cases, affected patients have their thyroid gland completely removed as a preventive measure while they are still children. The causes of the development of anaplastic thyroid carcinoma are not yet known.
What are the symptoms of thyroid cancer that you should look out for?
Thyroid cancer is hardly noticeable, especially in the early stages, and is often only discovered through routine examinations carried out by chance. For this reason, the signs of thyroid cancer tend to remain in the background and are hardly noticeable.
An existing tumour can only be felt with the fingers from a diameter of 1.5 cm and is hardly visible on the outside. The first acute symptoms often only appear when the cancer has already spread to the surrounding organs, such as the oesophagus, the lymph nodes or the windpipe.
Alarming thyroid cancer symptoms:
- Permanent hoarseness: caused by damage to the nerve pathways of the larynx by the thyroid tumour.
- Horner’s syndrome: the tumour damages the nerve pathways located in the area around the eye. This causes the pupil to constrict, the affected eyeball to sink in and the eyelid can no longer be fully opened upwards.
- Breathing difficulties: the tumour presses on the windpipe and causes considerable breathing difficulties.
- Discomfort when swallowing: the thyroid carcinoma narrows the oesophagus, making it difficult to eat and drink.
Prognosis and treatment for thyroid cancer
If the doctor detects an abnormality in the existing nodes, a scintigraphy is performed in which the patient is injected with a radioactive substance into the vein in order to localise and analyse the possible formation of malignant tumours more precisely. In some cases, the doctor decides to remove tissue from the nodule in question in order to arrive at a more precise diagnosis.
The treatment of thyroid cancer varies depending on the type and stage of the disease. In most cases, the thyroid gland is first removed completely by surgery. For smaller tumours, partial removal of the affected lobe of the thyroid gland is often sufficient.
If the tumour is limited to the thyroid gland and has not yet metastasised to the surrounding organs, postoperative radioiodine therapy is carried out after about two weeks to completely destroy the existing thyroid tissue in order to prevent further disease and tumour formation.
In the case of advanced thyroid cancer and metastatic spread, the only option is usually to start chemotherapy or radiotherapy to reduce or completely stop the progression of the life-threatening tumour.
Due to its poor chances of cure, anaplastic thyroid carcinoma rarely involves surgical removal of the thyroid gland. Thyroid cancer, which is incurable in many cases, is mainly treated with external radiation to prevent further growth of the tumour and to relieve acute symptoms.
Life expectancy and chances of cure for thyroid cancer
Patients suffering from papillary thyroid carcinoma have good chances of recovery compared to those affected by other types of carcinoma.
This type of thyroid cancer is curable for about 80 % of those affected, while follicular and medullary thyroid cancer have a somewhat worse prognosis of about 50 – 70 %. Unfortunately, according to current medical knowledge, anaplastic thyroid cancer can only be cured in the rarest of cases.