Hi Maureen! I participated in a clinical trial at Mayo that involved a PD-L1 inhibitor (Keytruda is a PD-1 inhibitor). My tumor was tested and found to be PD-L1 positive, so we were all pretty hopeful going in. Initially it seemed the cancer stabilized, but then the tumor started growing (this was over the course of 3 months). The immunotherapy was generally pretty tolerable, but it gave me crazy fevers. Like 105.7! Eek. My body would shake and shiver as the fever set in. I felt hopeful because it was obvious that my body was fighting something, but in the end the cancer ended up growing. My doctors still say they are unsure of the long-term positive effects that I may still be experiencing from the immunotherapy. Because it is so new, it is hard to really know how my body has reacted. Anyway, that is just my experience! I am SO hopeful and SO excited about this new way of attacking cancer cells. What a breakthrough we seem to be making! I have heard so many wonderful stories of people benefiting from these drugs.