Cytology tests play an important role in the diagnosis of thyroid diseases. They have been effective in reducing the rate of unnecessary thyroid surgery for patients with benign nodules and thyroid cancer. To address the terminology and other issues associated with cytology, a reporting system has been developed to facilitate effective communication among physicians treating thyroid diseases, the Bethesda system.

Papillary carcinoma is a common form of thyroid cancer that is caused by exposure to radiation energy. The disease usually presents as irregular nodules or cysts or tumors in the normal thyroid parenchyma. Once advanced, papillary carcinoma of the thyroid gland can be minimally or excessively invasive.