If you have symptoms that are suggestive of thyroid cancer, your doctor will take a history (present complaints, past history and family history), examine you and order laboratory tests and imaging tests of the thyroid gland. The exams and tests that may be done include:
History and Physical exam: Your doctor may ask you questions pertaining to:
The doctor will examine your neck, thyroid gland, voice box, and lymph nodes in the neck for any growths (nodules) or swelling. If a swelling or lump is present, your doctor will check the surface (if it is smooth or has nodules), temperature, movement with swallowing etc.
Blood tests—Blood sample will be tested to check the levels of the thyroid hormones (T3 and T4) and the thyroid-stimulating hormone (TSH). The thyroid-stimulating hormone is secreted by the pituitary gland in the brain. This hormone regulates the release of thyroid hormone. If your symptoms suggest medullary thyroid cancer, blood levels of calcium will also be checked.
Ultrasonography— This is a painless and non-invasive test that uses high-frequency sound waves to view the organs and structures inside the body. These sound waves cannot be heard by human ears. The pattern of the echoes produced when the sound waves are reflected from the internal organs creates a picture called a sonogram. The radiologist can differentiate healthy tissues, fluid-filled cysts and tumors on this picture. The picture produced when the sound waves bounce off the thyroid can help the doctor to see how many nodules are present, how big they are and whether they are solid or filled with fluid.
Radionuclide scanning—You may be given a very small amount of radioactive material. The radioactive material is taken up by the thyroid gland that makes the thyroid nodules show up on a picture. Some nodules may absorb less radioactive material as compared with other thyroid tissues. These are called cold nodules that can either be benign or malignant. Some nodules take up more radioactive material than surrounding thyroid tissue. These are called hot nodules and they are usually benign.
Biopsy— This is a confirmatory test to diagnose whether a nodule is cancerous or not. Your doctor will take a tissue to look for cancer cells. The tissue sample is examined by a pathologist (a doctor who specialises in diagnosing diseases by looking at cells and tissues under a microscope) for cancerous changes. Biopsy tissue can be taken through a needle or during surgery.
These are some of the tests that may be done if thyroid cancer is suspected. If you are diagnosed with any type of thyroid cancer, tests will be done to determine the stage of cancer as well. Some tests that are done for staging (determine the size of cancer and the extent of its spread) include magnetic resonance imaging (MRI) or computed tomography (CT) scan.