Subdivision
Although there are a large number of rare thyroid cancers, most tumors of the gland can be assigned to one of the four classic types. These classic types of thyroid tumor differ mainly in terms of the most appropriate treatment strategy. In addition, the exact type of tumor plays a decisive role in the prognosis. The four most common types of thyroid cancer are: papillary thyroid carcinoma follicular thyroid carcinoma medullary thyroid carcinoma
- Papillary thyroid carcinoma
- Follicular thyroid carcinoma
- Medullary thyroid carcinoma
- Anaplastic (undifferentiated) thyroid carcinoma
Papillary thyroid carcinoma
The so-called papillary thyroid carcinoma is the most common of the four types of thyroid cancer, accounting for approximately 60 percent of all thyroid cancers. The papillary form of thyroid cancer occurs much more frequently in women than in men. A typical feature of this type is that the tumor cells spread throughout the body primarily via the lymphatic system (lymphogenic metastasis).
For this reason, the cancer cells spread particularly in the area of the cervical lymph nodes. Papillary thyroid carcinoma generally has a very good prognosis. Although it is a malignant tumor, approximately 80 percent of affected patients can be cured with adequate treatment.
Due to the fact that the symptoms of this one of the four types of thyroid cancer occur very late, the tumor is often diagnosed by chance. At around 30 percent, the so-called follicular thyroid carcinoma is the second most common of the four thyroid cancers. It has also been observed that this form of cancer mainly affects women.
Both papillary and follicular thyroid tumors occur extremely rarely in males. In contrast to papillary thyroid cancer, the tumor cells in the follicular form spread mainly through the blood (so-called hematogenic metastasis).For this reason, daughter ulcers (metastases) are particularly common in the lungs or brain. Even with adequate treatment, the prognosis for this type of thyroid cancer is somewhat worse.
The so-called ten-year survival rate (how many of the patients are still alive after ten years?) for follicular thyroid carcinoma is approximately 60 to 70 percent. In both follicular and papillary thyroid carcinoma, it is assumed that ionizing radiation (such as X-rays) plays a decisive role in the development of the disease. For this reason, a particularly large number of cases can be observed in the vicinity of areas with previous nuclear reactor accidents (for example, in Belarus, Ukraine and Russia). In addition, radiation therapy for other types of cancer represents an important risk factor for the development of these four types of thyroid cancer.