<s>[INST] I had papillary cancer in the right thyroid. I ended up with a total thyroidectomy . I also had I-131 iodine treatment. This was in 2010. About 8 months ago I developed Sialolithiasis on the left side. Was treated with antibiotics and was taught how to massage parotid gland which has helped. Now I have developed a knot just below my submandibular gland on the right side. I was told it was a drooping of the submandibular gland due to my age which is 59. I was told this had nothing to do with my cancer or the removal of the thyroid. I have been looking up a forum to this nature which suggest otherwise. Multiple people have commented and their situation is like mine or very similar. Has there been any studies that might be a link between thyroidectomies or cancer with the salivary glands in particular the submandibular glands. I really feel uncomfortable with my situation. I have had a CT with contrast done whicChatDoctore back normal. Can you advise me what to do or give me your opinion. [/INST] Your problem is not related to your cancer or to the surgery. They have nothing to do with your present condition. However, they are related to the I-131 treatment that you took. It is known to cause decreased saliva production in both parotid and submandibular glands in a small percentage of patients. This leads to thickened saliva leading to stones or sialolithiasis, swelling of glands, retained secretions, Chat Doctor.  If the submandibular gland is just prominent and is not causing you any trouble otherwise (pain etc.), then I would suggest you to ignore it. Also, since the CT scan is normal, the likelihood of this being disease is remote. Other measures that you can take is to keep your mouth wet by using artificial saliva sprays. There is a possibility of stones forming in other salivary glands in which case they will have to be removed. Rest assured, it is not related to your disease. </s>