My father was diagnosed with Stage 4 melanoma in his lungs (very small spots) in early 2012. He was going to Sloan Kettering and was put on ippi. There wasn't much reaction to it initially so then he then transferred to Yale (closer to home) and was put on PD-1. Over the course of a year about 85% of the tumors shrunk which was wonderful news. However in his latest scan 3 spots on his ribs/chest popped up. The dr is now taking him off of PD-1 and putting him back on ippi. Has anyone had a similar experience?