Interesting, I listened to Dr. Linda Liau's presentation at the 25-minute mark several times and there is no mention of "LL describes long term survival as 20-25%". IMPO.
Per your comment "So what is LL referencing as 20-25%?" the only comment at the 25-minute mark in Dr. Linda Liau's presentation mention 25 people had over a 5-year survival rate.