Thyroid cancer statistics:
- Women get thyroid cancer three times more often than men
- Thyroid cancer is curable
- The survival rate for papillary cancer (the most common type) is 96%
- In most cases, surgery is enough for the successful treatment of cancer
- Iodine-balanced nutrition is effective prophylaxis for thyroid cancer
The thyroid gland is an essential organ for producing thyroid hormones (triiodothyronine and thyroxine), as well as the synthesis of thyroglobulin (a protein produced by the follicular cells of the thyroid).
The thyroid gland consists of 3 types of cells:
- A-cells - follicular, synthesizing thyroglobulin, which helps regulate a person’s metabolism
- B cells are epithelial, responsible for the formation of new follicles
- C-cells - parafollicular cells, belong to the neuroendocrine system and control how the body uses calcium
Types of thyroid cancer:
- Papillary thyroid cancer (the most common A-cells type)
- Follicular thyroid cancer
- Medullary thyroid cancer (C-cells)
- Anaplastic thyroid cancer
Other tumors (lymphoma, fibrosarcoma, sarcoma, epidermoid and metastatic cancer).
Different cancers develop from each kind of cell. The differences are significant because they affect how severe the disease is and what type of treatment is needed.
Carcinoma (cancer) - malignant formation, which is derived from cells of epithelial tissue of different organs.
Patients usually diagnosed with papillary and follicular types of thyroid cancer. However, these forms have a high success rate.
Papillary thyroid cancer
Papillary cancer is the most common thyroid tumor. This tumor develops in more than 85% of patients. It has a good response to therapy and a very optimistic prognosis for patients of all age groups.
The papillary tumor is located in one of the lobes of the gland (except for 10-20% of cases when the cancer is in both). It consists of follicular cells (A type) and grows extremely slowly, but is capable of affecting the lymph nodes of the neck. The female half of the population suffers from this disease three times more often than the male (this is a trend for all types of thyroid cancer).
Papillary thyroid cancer grows in the form of a node (with or without a capsule) with cystic cavities and fibrous areas. Half of the patients have calcification that often contains a brown colored liquid.
Treatment of papillary cancer
The main method of treating papillary thyroid cancer is surgery. The standard procedure is thyroidectomy (complete removal of the thyroid gland). If the tumor has affected the lymph nodes of the neck, the lymphadenectomy (lymph nodes removal) is performed.
Surgeons remove the lymph nodes of the following regions: pre-tracheal and paratracheal since they are the ones usually affected by the tumor.
Patients who underwent an operation to remove the thyroid gland are given lifelong replacement hormone therapy - a constant intake of synthetic analogs of thyroid hormones.
The final stage of treatment - radioactive iodine (radioiodine therapy). It is carried out for treatment of lymph nodes, the tumor of the thyroid gland itself and the treatment of aggressive subtypes of cancer (columnar cell and high-cellular tumor).
Metastasis of papillary thyroid cancer
Papillary cancer rarely produces metastases. In 35% of patients, cancer affects the lymph nodes. The uncommon spread of hematogenous metastases to the lung, bone, and brain occurs quite rarely.
Mortality and survival rate for papillary cancer
The survival rate for this type of cancer is very high, and mortality is relatively small.
Papillary carcinoma survival rate:
- stage I - 100%;
- stage II - 100%;
- stage III - 93%;
- stage IV - 51%.
Prognosis for papillary thyroid cancer is good for patients of age groups.
Follicular thyroid cancer
Follicular tumor accounts for 15% of thyroid cancer and occurs more commonly in women over 50 years of age. Follicular carcinoma does not expand beyond the thyroid gland, but in rare cases metastasizes into the lungs and bones.
Unlike papillary carcinoma, this type of tumor does not affect the lymph nodes, but the prognosis is just as favorable.
The tumor is a dense knot with clear boundaries and content of calcification in most cases. Intracerebral dissemination (spreading through the tissues of the gland) is not frequent.
There are cases of vascular invasion (germination in a blood vessel). During the development of such functional activity, patients can be diagnosed with metastasis to the lungs, bones, skin and even the brain.
Follicular thyroid cancer survival rate:
- stage I - 100%;
- stage II - 100%;
- stage III - 71%;
- stage IV - 50%.
The tumor develops slowly and has a good prognosis.
Medullary thyroid cancer
Medullary thyroid cancer is a form of thyroid tumor which forms in the parafollicular cells (C cells). These cells produce the hormone calcitonin. Medullary tumors are the third most common of all thyroid cancers. Metastases can be found in the lymph nodes, lungs, and liver.
Medullary thyroid cancer behaves more aggressively than the most common - papillary and follicular cancers. It metastasizes to the lymph nodes of the neck even at the early stage. The prognosis is good for patients under 40.
Medullary thyroid cancer survival rate:
- stage I - 100%;
- stage II - 98%;
- stage III - 81%;
- stage IV - 28%.
Anaplastic thyroid cancer
Anaplastic carcinoma (also called undifferentiated carcinoma) is a rare form of thyroid cancer, making up about 2% of all thyroid cancers. It is an aggressive form of the thyroid tumor that actively spreads throughout the body, primarily affecting the tissues of the neck.
The tumor is deadly.
The development of anaplastic thyroid cancer takes from 1 to 3 years, and it does not respond well to the treatment.
The 5-year survival rate for anaplastic carcinomas is 5-7%.
Other types of thyroid tumors
In addition to the above types of thyroid cancer, there are also tumors such as lymphomas, thyroid sarcomas, fibrosarcomas, epidermoid carcinoma. These tumors account for only 1-2% of cases.
The difference between thyroid cancers
Papillary cancer | Follicular cancer | Medullary cancer | Anaplastic cancer |
80% of all cases | 10-15% of all cases | 5-10% of all cases | 1-3% of all cases |
Occurs at the age of 30-50 | Occurs at the age of 40-60 | Occurs at the age of 40-60 | Occurs in patients over 65 |
Women get it more often than men | Women get it more often than men | Women and men suffer equally | Women get it more often than men |
Grows very slowly | May be more aggressive in elderly patients | It is accompanied by other endocrine diseases | Very aggressive |
Not prone to metastasis | Cancer cells can enter the bloodstream and metastasize into bone tissue or lungs | Can grow through the thyroid gland into the trachea and neck muscles | Actively grows into surrounding tissues |
Cancer cells are similar to normal thyroid cells | Tumor cells are spherical, round follicles | Develops from C-cells (parafollicular cells), which synthesize a hormone that regulates the growth of bone tissue | Tumor cells are atypical |
Easily treated | Can be treated with radioactive iodine | Treatment requires surgery | Does not respond well to treatment |
The prognosis is very good | Prognosis is good for patients under 50 | Prognosis for patients over 50 is not so good | Prognosis is not good |