A blood test consists of several different tests, as listed below: Thyroid hormone levels: Thyroid hormones are responsible for regulating metabolism. As a result, the doctor will use this test to check the levels of triiodothyronine (T3) and thyroxine (T4) in the body. Thyroid-stimulating hormone (TSH).: TSH is a hormone produced by the pituitary gland near the brain. This blood test helps in measuring the level of TSH. Tg and TgAb: Thyroglobulin (Tg) is a protein produced by the thyroid. In the body, thyroglobulin antibodies (TgAb) are produced in order to attack thyroglobulin (Tg). Thyroglobulin (Tg) levels in the body should be low after treatment. In case it continues to increase, more cancer is present. In order to measure Tg levels in the body, a tumor marker test can be performed.

Biopsies are performed under a microscope to examine tissue samples. Cancer can be detected through other tests, but only a biopsy can confirm a diagnosis. An examination of a nodule with a biopsy can reveal whether it is cancerous or benign.

By using sound waves, an ultrasound creates a picture of the internal organs to determine if cancer has spread. Over the neck area, an ultrasound probe is guided over the skin. With high-frequency sound waves, the doctor can observe the size of the thyroid gland and any nodules, including whether they are solid or fluid-filled sacs called cysts, and diagnose accordingly.