The first step in developing a personalized thyroid cancer treatment plan is getting an accurate diagnosis. Various tests and procedures designed for diagnosing thyroid cancer are used to evaluate and stage the disease. For example, an ultrasound may help the oncologist inspect the thyroid for nodules, and a biopsy may be taken to retrieve and test tissue samples. An X-ray of the chest may reveal whether cancer has spread to the lungs.
Common tests used for diagnosing thyroid cancer include:Biopsy
A sample of throat tissue or cells is required for a biopsy, which must be conducted before treatment can begin. The types of biopsies typically used for diagnosing head and neck cancers are:
Fine needle aspiration (FNA): With this test, a very thin needle attached to a syringe is used to extract (aspirate) cells from a tumor or lump. This approach can be particularly useful for several situations that can occur with laryngeal cancer.
Incisional biopsy: If further testing is needed after a fine needle aspiration, a small piece of tissue may be cut from an abnormal-looking area. Because the larynx is deep inside the neck, removing samples involves a complex procedure. Therefore, biopsies of this region are usually done in an operating room, with general anesthesia administered to prevent any pain.Imaging tests
X-ray: An X-ray of the chest may be taken to check if the cancer has spread to the lungs. Cancer will not be present in the lungs unless it is in an advanced stage.
CT scan: Computed tomography (CT) scan (also known as a computed axial tomography scan, or CAT scan) is one of the most commonly used tools for the screening, diagnosis and treatment of cancer. This test for thyroid cancer is usually used to see if the disease has spread to other areas of the body, but may also sometimes be used to guide the biopsy needle.
MRI: Magnetic resonance imaging (MRI) is an imaging tool designed to create detailed, cross-sectional pictures of the inside of the body. Using radiofrequency waves, powerful magnets and a computer, MRI systems may distinguish between normal and diseased tissue. MRI may be used to look at the brain and spinal cord, locations where thyroid cancer may spread (metastasize).
Nuclear medicine scan: The most common test used for patients with thyroid cancer is a radioiodine scan, which involves swallowing or injecting a small amount of radioactive iodine, or I-131. This test is often used in patients with differentiated forms of the disease (papillary, follicular, Hürthle cell). It may be used to identify abnormal areas of the thyroid gland, or to determine if the cancer has spread to other areas of the body.
PET scan: Positron emission tomography (PET) is a nuclear imaging technique that creates detailed, computerized pictures of organs and tissues inside the body. PET scans are very sensitive, but they do not show much detail, so they will often be performed in combination with a CT scan (called PET/CT). In many cases, we use the GE Discovery™ PET/CT 600 scanner, a state-of-the-art four-dimensional CT scanner produces detailed cross-sectional X-ray images of structures in the body. It also enables our radiologists to plan treatment in accordance with patients" breathing patterns.
Ultrasound: Also known as sonography, this non-invasive procedure can help doctors determine the size of nodules on the thyroid and see how many are present. It may also help determine whether the suspected nodule is solid, or filled with fluid. Sometimes, ultrasound is also used to guide the biopsy needle when nodules are small.Lab tests
Various laboratory tests are used to diagnose thyroid cancer. They include:
Advanced genomic testing: Genomic testing examines a tumor on a genetic level to look for the DNA alterations that are driving the growth of cancer. By identifying the mutations that occur in a cancer cell"s genome, we can better understand what caused the tumor and tailor treatment based on these findings.
Nutrition panel: With this test, we evaluate patients for deficiency of nutrients, such as vitamin D and iron. The test helps us identify the nutrients patients need replaced or boosted to support their quality of life.
Other lab tests that may be used include a thyroid function test, as well as level tests of the thyroid-stimulating hormone (TSH), triiodothyronine (T3) and thyroxine (T4). Levels of the protein thyroglobulin are also typically tested before and after surgery.Laryngoscopy
A laryngoscopy is often used to examine the back of the throat. The two types of laryngoscopy are indirect laryngoscopy and direct laryngoscopy. Because the thyroid gland is so close to the vocal cords, thyroid tumors may sometimes affect them. For this reason, your doctor may want to examine the cords first with special tools, such as a laryngoscope, if you are scheduled for surgery.
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