How big was the tumor? It is papillary cancer, that is the type. Pap cancer is the most common form of thyroid cancer and highly curable (around 99%). I have never heard of a columnar variant, but I am not a doctor, only a patient. If your tumor is 1.5 cm or more, it is highly suggested that you undergo RAI, any smaller they do not recommend it. If you have more than 1 tumor, it is suggested that you undergo RAI. Google any words that concern you with the tag thyroid cancer, you may get more information, but most of it you would need a background in medicine to understand. The most agressive forms of thyroid cancer are Medullary and Anaplastic, you don't have those, so relax and listen to your Endo or surgeons.
I have one tumor with size of 1 cm. Thank you for your reassuring words.
I also was able to find some info on MedHelp with links to articles, more posts, etc.
Hoping this helps - please let us know how you are doing!