The thyroid gland is a butterfly-shaped gland in the middle of the neck, located just below the voice box. It makes thyroid hormone. Thyroid hormone has an effect on nearly all tissues of your body by regulating your metabolism. Metabolism is the breakdown and use of food that you eat or energy that is stored in your body. Your metabolism affects your heart rate, blood pressure, body temperature, and weight.
Thyroid cysts are enlarged fluid filled regions of the thyroid gland. These cysts range in size and may expand and enlarge suddenly. Rapidly expanding cysts may cause pain, difficulty swallowing, and rarely, difficulty breathing. Most cysts of the thyroid are not cancerous (benign).
Bleeding may occur within the cyst. If the bleeding is severe, the cyst may get larger and produce problems in the neck, including swelling that may produce pain and difficultly swallowing. If the vocal cords are compressed, hoarseness may occur. If the windpipe is compressed, you may have difficulty breathing.
A thyroid cyst is diagnosed through physical exam. The diagnosis can be confirmed by an ultrasound exam of the neck. This creates a picture by bouncing sound waves off the thyroid gland. Sometimes the cysts are drained using a fine needle. The fluid is then sent to the lab where it can be examined. This is done to see if any cells in the fluid are cancerous. If they are found to be cancerous, you will need further treatment.
If the fluid in your neck does not show evidence of cancer, your caregiver may just want to monitor you with yearly ultrasound exams. Sometimes cysts need to be removed surgically.