Thyroid gland cancer
Thyroid gland cancer
Thyroid gland cancer is a term for a thyroid tumor. The correct designation here is a thyroid carcinoma however, which is a malignant tumor. The main risk factors are ionizing radiation, which is dangerous especially at an earlier age. Other factors are genetic predisposition, autoimmune inflammations, a lack of iodine or a disorder in production of thyroid hormones.
The thyroid gland is an organ found on the front of the neck. It's located in front of the trachea and under the thyroid cartilage. It's main purpose is the production of hormones triiodothyronine (T3) and thyroxine (T4), which are applied in many processes in our organisms, and calcitonin, which lowers the calcium levels in blood. To simplify, the thyroid gland tells other organs what to do.
What is cancer?
Cancer, or a tumor is a cell disorder, which due to their damage start growing and reproducing uncontrollably. Tumors are divided into malignant and benign. Benign tumors usually grow slowly, don't damage surrounding tissue and do not metastasize, do not form secondary nodes. On the other hand, malignant tumors grow aggressively, penetrate into surrounding tissue and form metastases, which are the most common cause of death.
Benign thyroid cancer
Benign thyroid tumors are far more common than malignant ones, which form around 1% of all malignant tumors. The boundary between benign and malignant tumors is not entirely clear however. The most common benign tumor is an adenoma.
Thyroid adenoma is a benign tumor, which can either be found separately or in greater numbers, which is referred to as a nodular struma. Thyroid adenoma mainly affects women, usually above the age of 40. Generally, we divide nodules into „cold“ and „hot“. Cold nodules show no iodine metabolism and have no endocrine manifestations. These are often malignant, such as carcinomas. Hot nodules on the other hand show increased iodine metabolism. They often produce an excessive amount of hormones (hyperthyroidism) a subsequently change blood levels. An example of a hot nodule is an adenoma. In some cases it can turn malignant.
Malignant thyroid cancer
Malignant thyroid tumors occur somewhat rarely. Unfortunately, their numbers have a growing tendency in the last few years. A non-negligible effect on development of this disease are neck irradiations or lingering radiation (from nuclear bomb testing, for example).
Thyroid gland carcinoma affect around 1 in 10 000 people. Most of them have no significant symptoms. A stiff shape on the front of the neck, a thyroid nodule, can often be felt, but it tends to be painless with no noticeable effects on the body. It's advantage is the fact that it only metastasizes in 3% of all cases, which gives us a good chance of recovery. Organs in which theses secondary nodes tend to develop are usually neck lymph nodes, lungs and bones.
Diagnosis of thyroid cancer
When diagnosing thyroid cancer, we first need to examine the thyroid gland function biochemically. A biochemical examination is usually done by a blood sample, which provides us with important information about the state of the organism and its organs. Ultrasound examination will help us determine the size of the nodule, or eventually of the gland itself and will allow us to check its surroundings. Should a nodule be found, we also take a tissue sample by a thin needle, which will reveal its biological activity, whether it is malignant or benign. Determining the tumor's properties will give us both the treatment needed and the prognosis.
Treatment of thyroid cancer
Thyroid cancer treatment is based on the disease's character, which sets both the procedure and the prognosis.
When dealing with an adenoma, the min medication used in therapy are thyrostatics, drugs inhibiting the gland's activity. The purpose is to normalize the gland function before deciding a permanent treatment. Thyrostatics can have a range of side effects such as reddened face, itchy skin or increased temperature. Surgical treatment (thyroidectomy) is the most common permanent solution of an adenoma. The entire gland is usually not removed, only the affected lobe. A disadvantage of a surgical procedure is the risk of damaging the recurrent nerve, which leads to a partial or complete loss of voice or breathing issues. In established workplaces this risk is only present in about 1% of all cases, however. Radioiodine treatment is used in adults in which a surgery would be too risky. The gland's function optimizes usually within 2-6 months. The prognosis of adenomas is very positive, although proper treatment is still necessary. An untreated adenoma is a life threatening condition.
The basis of treating thyroid carcinoma is a complete removal of the gland, a total thyroidectomy (TTE). Further steps in treatment depend mainly on the type of the carcinoma. The most common one, a papillary carcinoma (80%) accumulates iodine well, which is why radioiodine is administered for 6 to 8 weeks after the removal, to show any possible metastases. Radioiodine treatment consists of radioiodine being absorbed by cells of he thyroid gland, which capture iodine in blood, and the cells being subsequently destroyed. It is mainly used to remove remnants of the gland after a TTE, which are present in about 95% of patients. In other tumors, which for example do not accumulate iodine, a radiotherapy is used. The problematic of treating thyroid carcinoma is very complex and always depends on a series of factors, which decide the course of treatment.