With cancer becoming such a feared disease around the world and with the incidence of the various types of cancer on the rise, more and more people want to be better informed about such conditions. They want to know what warning signs they should be looking out for and what screening tests they should be doing. So if you are one of them and you want to know more about thyroid conditions then read ahead. Worldwide the incidence of http://www.sydneybreastspecialist.com.au/thyroid_cancer.html is on the rise. The incidence ratio F: M is about 5:1. Malignancies can arise from Thyroid cells proper – Papillary carcinoma, Follicular carcinoma, Mixed (both papillary and follicular), Atypical. These are also called differentiated thyroid carcinoma and they have specific characteristics like good prognosis, 50% is multifocal, 50% is bilateral, produces thyroglobulin, takes up radioactive iodine 131.
Then you have the Non thyroid cells – The commonest is the medullary carcinoma which arises from the C cells.When you visit a thyroid specialist for treatment of thyroid conditions, they would most probably end up using radioactive iodine. Radioactive iodine produces Beta and Gamma rays. Beta rays have a penetration of 1mm therefore they are therapeutic and can be used to destroy remnant thyroid tissue after NTT. Gamma rays have a greater penetration are used for diagnostic purposes in the radioisotope scan. In the radioisotope scan 100% functioning cells appear red, 50% functioning cells appear orange and nonfunctioning or background cells appear green.These radioisotopes are also taken up by the salivary glands – parotid, submandibular and sublingual glands. They swell up and can cause isotope induced sialedenitis.
When there is a thyroid nodule we take a detailed history asking for hyperthyroid, hypothyroid or pressure symptoms. Then we do a detailed head and neck examination including the lymph nodes. Then we do investigations such as T4, T3 and TSH levels, isotope scan, ultra sound scan, serum thyroglobulin levels and FNAC ( which can be direct or ultra sound guided). When FNAC is done the results are given according to the Bethesda or Thy classification. Here grade 1 and 2 are benign, grade 3 is suspicious, grade 4 is atypical and grade 5 is carcinoma. Papillary carcinoma can be diagnosed only by nuclear pattern of the cells therefore it can be diagnosed after an FNAC. But follicular carcinoma can be diagnosed only if there is vascular invasion and capsular infiltration which cannot be diagnose by FNAC. But if there is a secondary and the FNAC from the secondary has follicular cells then it can be diagnosed.