Malignant Thyroid Disease
The thyroid gland is often described as a “butterfly” or “bow tie” shaped structure. It is located in the central lower portion of the neck, almost exactly where a bow tie would be located.
The incidence of thyroid malignancies is increasing rapidly in this country, but most thyroid cancer is highly treatable and curable. Not all growths are cancer. It is very common for nodules (small growths) that are benign to develop within the thyroid gland. There are many other types of conditions that can arise in the thyroid gland that can lead to either overactivity (too high a level of thyroid hormone) or underactivity (too low a level of thyroid hormone).
In the early stages of thyroid cancer, there are no symptoms and no indications in blood work that the disease is present. In advanced stages, symptoms can include a change of voice, dysphagia (trouble swallowing) and dyspnea (labored breathing).
The first indication of thyroid cancer is most often the discovery of a lump in the neck within the thyroid gland. In other patients the first indication may be an enlarged lymph node on the side of the neck that is found to contain thyroid cancer cells. Typically the lump is detected either by the patient or the patient’s physician during a routine physical exam. The diagnosis is often performed by an ultrasound-guided fine needle aspiration, which withdraws cells from the tumor for analysis to determine if the tumor is benign or malignant. In some circumstances where cytology (analysis of the cell) is inconclusive, diagnosis of the tumor may involve the removal of a portion of the gland. Incidental malignancies may also be identified while removing the thyroid gland for a presumed benign condition.
There are four types of thyroid cancer: papillary (the most common), follicular, medullary and anaplastic (the least common). Papillary carcinoma grows slowly and can spread into the lymph nodes in the neck. Follicular carcinoma can move into other parts of the body, typically the bones and the lungs. Both of these types of thyroid cancer, if caught early, are highly curable. Medullary thyroid carcinoma is formed in C-cells of the thyroid gland and frequently spreads to lymph nodes and other parts of the body before the cancer is detected. Anaplastic carcinoma is a rare, aggressive, often fatal type of thyroid cancer.
The primary treatment for thyroid cancer is the surgical removal of the entire thyroid gland along with associated lymph nodes. It is critical to preserve the nerves of the vocal cords and the parathyroid glands during surgery. The preservation of the vocal cord nerves is important to retaining a normal voice. The preservation of the parathyroid glands is important to maintaining normal calcium levels in the body. A highly experienced surgeon is required for this type of operation. In the treatment of papillary and follicular carcinoma, the use of radioactive iodine can help treat cancer that has spread outside of the neck to other parts of the body. However, radioactive iodine is not appropriate for all patients. The decision to treat a patient with this form of therapy is made after the results of the final pathology report is obtained following surgery.
The ability to address and manage complex disease situations can have a huge impact on the outcome of the treatment. Surgeons can use nerve grafts and transfer tissue from other parts of the body to effectively replace what was surgically removed in the treatment of advanced forms of the disease. Addressing these complex types of problems can restore the patient’s function and quality of life after removal of the diseased thyroid. Reconstruction of the esophagus and trachea also helps avoid the necessity of other major procedures.
The successful management of thyroid cancer requires a team approach to the disease including an experienced thyroid pathologist, thyroid cytopathologist, a thyroid surgeon, an endocrinologist and a nuclear medicine specialist. Medical oncologists can also play a role in more advanced stages. It is invaluable to the patient to have the entire team working in a coordinated fashion. This begins with ensuring that the initial biopsy, as well as the final post surgical pathology are accurate and providing the appropriate information to gauge the clinical decision making.