The first thing you need to do, is relax.
Understand that IF it is cancer that the survival rate for thyroid cancer is high. Thyroid cancer is slow growing. The chances of it being spread to other areas of the body or to the lymphnodes often depends on the type of cancer you have. There are different forms
Papillary and/or mixed papillary/follicular " 78%
Follicular and/or Hurthle cell " 17%
Medullary " 4%
Anaplastic " 1%
I was diagnosed with mixed papillary/follicular carcinoma in 2007. I've been fighting ever since.
I'm not gonna pretend with you... your nodule is big. My biggest measured at 4.8 cm. The smallest 4.6 cm. Not too much bigger then yours, they wanted them removed for that reason alone.
Please note, that thryoid cancer is not detectable by blood tests. Many noncancerous thyroid conditions can cause an elevated thyroglobulin level thus the reason the blood tests are not used to determine cancer.
I have provided you with some links to read up all about thyroid cancer and disease. These links have helped me so much, from when they first discovered my nodules and throughout my fight.
Best of luck to you...
Feel free to contact me if you need support, I've been where you are and will be for the rest of my life!