Serum Thyroglobulin Measurement by Mass Spectrometry in the Follow-Up of Thyroid Cancer Patients

6 Asymptomatic Paget’s Disease — To Treat or Not to Treat Throughout most of the 20th century, thyroid carcinoma was considered a rare cancer with a low death rate. During the last 20 to 25 years, however, incidence rates of thyroid cancer have risen exponentially across the world. In combination with the low cause-specific mortality rate of thyroid cancer, this increase has led to huge numbers of living thyroid cancer patients. Stefan K. Grebe, M.D., Ph.D., of the Department of Laboratory Medicine and Pathology at Mayo Clinic in Rochester, Minn., says, “We predict that by the end of the second decade of the 21st century, thyroid cancer will be the third most common diagnosis in a living cancer patient, just behind carcinomas of breast or prostate, and ahead of colorectal malignancies.” Dr. Grebe explains, “While most of these thyroid cancer patients will not die of their disease, between 15 and 40 percent will suffer some form of recurrence during their lifetime, creating a growing need for cost-effective and accurate laboratory tests to detect or predict recurrence in order to minimize use of much more costly alternative diagnostic procedures, as well as to reduce morbidity due to delayed therapeutic interventions.” Fortunately, a good thyroid tumor marker is available. Thyroglobulin (Tg), which serves as scaffold and substrate for thyroid hormone synthesis, is expressed exclusively in the thyroid gland. It should therefore become undetectable in the blood of the majority of thyroid cancer patients, because their gland is usually removed in the course of therapy. However, M. Regina Castro, M.D., of the Division of Endocrinology, Diabetes, MetaboSerum Thyroglobulin Measurement by Mass Spectrometry in the Follow-Up of Thyroid Cancer Patients