Correlation Vitamin D Level to Endocrine Autoimmune Toxicity Due to Immune Checkpoint Inhibitors

The purpose of this research study is to see if the amount of vitamin D in ones blood makes it more or less likely to develop thyroid gland toxicity when being treated with immunotherapy that blocks the activity of proteins called programed death-1(PD-1) or programmed death ligand-1 (PD-L1). Immunotherapy is treatment that makes changes to the immune system to try to fight cancer. Immunotherapy treatments that block the activity of important parts of the immune system called PD-1 and PD-L1 are used to standardly treat many different types of cancer and can cause thyroid toxicity in certain people. In this study the treatment for your cancer is not research treatment but standard of care determined by your oncologist. Blood will be drawn before starting treatment to determine the amount of Vitamin D and also to assess thyroid function. Also questionnaires will be completed before starting treatment and while on treatment to assess symptoms you are experiencing.