What Causes Skin Rash And Muscle Aches, Who Have Had Thyroid Cancer?

I am presently being observed for a skin rash and muscle aches. Suspect dermatomyositis. Have had blood work done. No inflammation. Skin biopsy suggests connective tissue disease. Antibodies slightly elevated. Neurologist tested muscle strength said fine. Ct scan shows nodule on lung. I have had thyroid cancer. Am awaiting results of muscle enzyme test and further blood work. Statin drug has been stopped since I have had muscle aches while taking them. Dr. Has had me on for 12 years. Could the. Vytorin be the cause of this. I am confused and frightened by the lack of a diagnosis so far.