My father has stage 4 and was able to get in on the Ipilimumab trial under a "compassionate use." He was lucky, it worked and ALL his tumors either disappeared completely or shrunk markedly (and he was able to only have two of the four treatments). He's been fine for a year and a half although now it looks like one tumor may have come back so the Angeles Clinic is testing him to see if he can take the NRAS treatment.
Good luck!