You had great surgical results, congratulations. I just finished 2 1/4 years of a PDL1 inhibitor for metastatic SCC originating in my ear ,and mets ( over the course of 10 years) in lung, muscle, kidney and lymph nodes. I was on Libtayo, not Opdiva. The most prominent side effect for me was tiredness, but also a change in appetite and the taste of food. That is slowly improving having been off infusions for 5 months. My tumor did test high for PD1/L1 which helped to make the decision for using Libtayo. Immunotherapy should not be taken lightly, as very serious side effects can occur. My husband was on Keytruda, another PDL1 blocker, for 5 months and he is now hypothyroid from immune system attacking his thyroid. Make sure you discuss all the side effects before starting treatment. Luckily for me I had a great response from the drug and it was worth all the minimal side effects. Best of luck to you zzonner.