The small butterfly-shaped thyroid gland is in the front part of the neck, and thyroid nodules are small lumps of tissue that form in the thyroid. The nodules are relatively common and can be found when doing a physical examination, routine health check-up, or imaging test. Although many thyroid nodules are not cancerous, others may need to be evaluated further to identify their type and/or if treatment is indicated.
An imaging test called a thyroid scan can be used to determine how active a thyroid nodule is and is a type of nuclear medicine test. Nodules can be classified as hot, warm, or cold according to uptake. These variations are important for understanding thyroid function and determining if further investigations are indicated. Under the supervision of Dr. Nikunj Jain, Molecular Diagnostics and Therapy offers diagnostics to complement the diagnosis of thyroid conditions and patient information for clinical decision-making. What Is a Thyroid Nodule? Thyroid nodules are lumps formed by an abnormal growth of thyroid tissue within the gland. They can be present as one or more nodules. Nodules can be solid, fluid, or both solid and fluid. Most thyroid nodules, however, are without symptoms and are detected during a medical examination procedure or when people obtain imaging tests such as ultrasound or CT as part of a medical evaluation.
Large nodules may cause visible neck swelling, difficulty swallowing, throat pressure, or voice changes. Some thyroid nodules (nodules) produce too much thyroid hormone, and others cause no hormone production. In the thyroid scan, this can tell whether the nodule is working and provide useful information to further evaluate the nodule. What Are Hot Thyroid Nodules? A hot nodule is an area of the thyroid that takes up more radioactive tracer than other parts of the thyroid. It will be noted that this uptake is generally increased, suggesting the nodule is more active. These little nodules can make thyroid hormones without the normal controls. In some instances, they might also be part of the reason for hyperthyroidism, which is a condition in which there is too much thyroid hormone in the body. What Are Cold Thyroid Nodules? An area that takes up less tracer than the rest of the thyroid appears ‘cold’ on the scan. This decreased uptake indicates that the nodule is less active or not working. Don't assume that having cold nodules means that there is a severe problem. Most cold nodules are benign, such as cysts or colloid nodules, but some need further evaluation, and certain thyroid cancers can also appear cold. What Happens If a Thyroid Nodule Is Found? The next steps depend on the scan results, ultrasound findings, thyroid hormone levels, and the person’s risk factors. In hot nodules, doctors might also test the levels of thyroid hormones to see whether the nodule is causing hyperthyroidism. If a hot nodule is causing symptoms or producing too much hormone, treatment may be needed.
In the case of cold nodules, thyroid ultrasound is frequently also ordered to assess the nodule’s size, composition, and margins. Fine-needle biopsy with aspiration may be requested if ultrasound appearance and/or clinical risk suggests sampling is required. Most thyroid nodules are not cancerous, and not all need treatment or biopsy. Depending on the total clinical evaluation, the right course of action may be observation, further testing, or treatment. The Importance of Thyroid Diagnostic Evaluation Thyroid issues will influence a number of body functions and metabolism, as well as heart rate and energy level. So it is essential to know what type of thyroid nodule is present to understand thyroid health. A scan of the thyroid provides functional information, a blood test provides information about levels of thyroid hormones, and a scan using ultrasound shows the structure of the thyroid. The investigations provide data of complementary value which aids Healthcare Professionals in a decision-making process.
Dr. Nikunj Jain, at Molecular Diagnostics and Therapy, provides nuclear medicine diagnostic support for thyroid conditions. The results will help a doctor who treats thyroid patients understand the activity of the thyroid and decide on the appropriate next course of action for a patient's health. Conclusion Based upon the amount of radioactivity that the thyroid takes up during the scan, thyroid nodules are classified as hot or cold. Hot nodules take up more tracer and may produce excess thyroid hormone, though they are rarely cancerous. Cold nodules take up little tracer. Most are benign, but some may be malignant, so further evaluation may be needed.
The thyroid scan is used to help determine how much of the thyroid tissue is working, rather than being used to make a diagnosis of cancer. It cannot confirm or rule out cancer on its own. If necessary, additional information can be obtained from thyroid blood tests, ultrasound, and fine needle aspiration biopsy (FNAB). The result of the scan and the background health history of the person could lead a Healthcare Professional to suggest investigations and management.