Papillary and follicular cancer account for over 80-85% of all thyroid cancers and are sometimes referred to as well-differentiated thyroid cancer (carcinoma). Their appearance under a microscope is responsible for their names and occasionally some contain elements of both (follicular variant of papillary carcinoma).
Papillary Carcinoma and its follicular variant may occur at any age. Certainly, any thyroid mass in a child or teenager should be considered highly suspicious for thyroid cancer. Most papillary cancers present as a thyroid nodule, although some present as a mass in the neck representing a lymph node involved by papillary cancer. Papillary cancer may be multicentric (affecting multiple sites within the thyroid gland) and tends to preferentially metastasize to regional lymph nodes in a high percentage of cases, more commonly in those tumors which are larger, i.e. over 3 – 4cm. Fortunately, it less commonly spreads to other organs. The first group of lymph nodes usually involved lie along the trachea below the thyroid gland (paratracheal lymph nodes) and the second group lie in the lateral neck along the jugular vein and behind it (cervical nodes). While not necessary in all patients, complete removal of the lymph node compartments containing thyroid cancer can control it in most patients. The side effects of this type of surgery can be minimized in most patients.
In general, the best treatment for papillary and follicular thyroid cancer involves total thyroidectomy (complete removal of the thyroid gland) with or without an associated removal of the regional lymph nodes. In selected cases, radioactive iodine ( a radioactive pill) is given following the surgery to identify and destroy any remaining thyroid cancer cells not removed by surgery, or that may have escaped to other sites.
A whole body scan follows administration of this drug, to determine if there are any foci of unrecognized disease. The patient can then be followed periodically by the thyroid specialist by examination, blood tests and occasionally ultrasounds and scans to be certain that the thyroid cancer has not recurred.
Follicular Cancer affects women somewhat more frequently than men and behaves somewhat differently than papillary cancer. It rarely spreads to lymph nodes but may spread via the bloodstream to other organs. Its treatment is not much different however from papillary cancer, although lymph nodes only rarely have to be removed.
Hurthle Cell cancer is most often a variant of follicular cancer although some are variants of papillary cancer. Hurthle Cells have a unique appearance under the microscope. However, their behavior and treatment is not much different than that for papillary and follicular cancer.