Hello Sir ,
Welcome to Health Care Magic
As in your case let me tell you firstly FNAC procedure does cause some local problems like pain etc. increase in size of swelling also may be possible as thyroid is a endocrine gland
so it is very richly supplied by vasculature ( Blood Supply) so performing FNAC may cause some hemorrhage which might exhibit as increase in size of swelling but all these symptoms will subside in due course of time automatically , nothing is required for them .
Now secondly about youur diagnosis of FOLLICULAR NEOPLASM
OF THYROID IS A Cancer of the thyroid and is the most common endocrine malignancy. The initial treatment for cancer of the thyroid is surgical removal . The exact nature of the surgical procedure to be performed depends for the most part on the extent of the local disease. A consensus approach might be to perform a total thyroidectomy
if the main tumor
is larger than 1 cm in diameter or if there is extrathyroidal involvement ( involvement of other than thyroid organ). After the surgery there are supplements that are need to be taken lifelong .
Wishing you all the best .