Good morning @suea and welcome to Mayo Connect. I'm sorry that you feel so awful. Colds are so inconvenient, to everything. I would wait until Tuesday or Wed and call your doctor to see if you should wait for your next treatment. Since I am fairly new here I don't know your history. Can you tell me about yourself? What kind of cancer do you have? If you have a pulmonologist I'd call her now and see if she can help with a Z pack or something else to help you get rid of your cold quickly. I have multifocal adenocarcinoma of the lung and my pulmonologist prescribed it for me so that I wouldn't have to delay a procedure that I needed.
I have heard many different things about immunotherapy but I don't know much about it. How are you holding up? Are your side effects tolerable? Can you tell me more about it from you special case?