The Thyroglobulin test is also known as TGB or Tg test. This test helps to monitor the treatment of thyroid cancer. It is also used to detect if there is any recurrence of thyroid cancer. This test can also be used to determine the cause of hypothyroidism and hyperthyroidism. The Thyroglobulin test is done: • Prior to treatment of thyroid cancer • After the completion of treatment of thyroid cancer • Before and after radioactive iodine therapy • To detect if there is recurrence of thyroid cancer • To monitor the effectiveness of treatment for conditions such as Grave’s disease • Along with other thyroid tests to detect thyroid disorders