Poorly Differentiated Papillary Thyroid Cancer

Has anyone had Poorly Differentiated Papillary Thyroid Cancer. The cancer has come back twice and I have had two surgeries to remove the tumors. I am being offered 30 sessions of proton therapy as a prevetative against it coming back again but I am very concerned about side effects. I would greatly appreciate anyone's insight into similar xircumtances or experiences with radiation for this type of cancer. Thank you.