How Common Is Differentiated Thyroid Cancer?

Differentiated thyroid cancers are the type of thyroid cancer where the cancer cells greatly resemble normal thyroid cells on microscopic examination. They are the most common types of thyroid cancer.

• The thyroid gland is a butterfly-shaped gland present in the front of the neck, just below Adam’s apple (thyroid cartilage).
• It forms the hormones required to regulate the metabolism, heart rate, body temperature, and blood pressure.
• The hormones are important for fetal growth and development, including brain development.

The gland has two main types of cells called follicular cells and parafollicular cells (or C cells). The follicular cells are responsible for making the thyroid hormones that regulate metabolism, whereas the C cells produce the hormone, calcitonin, which controls calcium utilization by the body. Differentiated thyroid cancers develop from follicular cells.

Differentiated thyroid cancer is of three types: papillary, follicular, and Hürthle cell cancer. 

Knowing the type of thyroid cancer helps determine the disease outlook (prognosis) and plan appropriate management strategies.

Papillary cancer

Also called papillary adenocarcinoma or papillary carcinoma of the thyroid, papillary cancer accounts for the majority (about 80 percent) of thyroid cancers.

• Generally slow-growing cancers, they tend to spread to the neck glands (lymph nodes) and respond well to treatment, which rarely results in death.
• They are almost three times more common in women than in men and usually present in adults aged 34 to 40 years old.

Papillary cancer is of various subtypes depending on the microscopic appearance of the cancer cells. Most papillary cancers have a good prognosis. Some of its less common types (such as columnar, insular, and diffuse sclerosing) tend to grow and spread faster than the more common subtypes (such as mixed papillary-follicular variant).

Follicular cancer

Also called follicular adenocarcinoma or follicular carcinoma of the thyroid, follicular cancer is the second most common thyroid cancer, accounting for about 10 percent of all thyroid cancer cases.

• It generally affects people living in areas with iodine-deficient diets.
• Just like papillary cancer, follicular cancer is also three times more common in women than in men and generally present in individuals in their fourth to sixth decade of life.

Their outlook is good in most cases although not as good as that of papillary cancer. Follicular cancer does not spread to lymph nodes, but it tends to spread (metastasize) to other sites, such as lungs or bones.

Hürthle cell cancer

Also called oxyphil cell carcinoma, Hürthle cell cancer is often considered a subtype or variant of follicular carcinoma, and accounts for about two to three percent of all thyroid cancers.

• Hürthle cell cancer generally presents in the fifth decade of life.
• It is more common in women than in men.