Thyroid Cancer

Diagnosis

Most tumors of the thyroid gland are benign, but patients should seek medical attention if they have any related symptoms. Physicians consider risk factors, such as excessive exposure to radiation and a family history of thyroid tumors, when diagnosing thyroid tumors. Blood tests cannot confirm the presence of thyroid cancer in most cases, but can be used to determine if the thyroid gland is functioning normally.

Mayo doctors use fine needle aspiration (FNA) to gather cells (biopsy) for a pathologist to view under a microscope. FNA is generally the most appropriate initial test to distinguish between benign and malignant tumors. Thyroid and octreotide (chemical) scans are performed using substances such as radioactive iodine or hormones tagged with radioactive material, to determine if the cancer has spread to other tissue. Images from X-rays, magnetic resonance imaging (MRI), computed tomography (CT) scans, positron emission tomography (PET) and ultrasound are used when necessary to learn more about the tumors. Blood tests such as thyroglobulin, calcitonin and carcinoembryonic antigen (CEA) are sometimes useful in monitoring tumor extent/progression in selected patients with thyroid cancers.

Thyroid cancers are most often not inherited, but some patients with medullary thyroid cancer may have genetic alterations that can be associated with other endocrine cancers such as multiple endocrine neoplasia syndromes or familial medullary thyroid cancer. Under some circumstances genetic testing may be appropriate in patients and their family members with medullary thyroid cancer.