Tracey, I'm sorry to hear that your friend's cancer has spread.  It would be impossible to say how much longer she can live because there are so many factors that can affect life expectancy.  Some people who have metastasis to several parts of their body opt for aggressive treatment, maybe even a clinical trial, and manage to stay stable for months and even years.  In fact, I know quite a few people who have lived for years with Stage IV breast cancer.  Metastasis is dangerous, but if she just has small spots, then treatment might stop the spread or even reduce the size of the cancer.  If your friend has extensive cancer throughout her lungs, bones and liver, then she or her family might want to contact the local Hospice organization.  Everyone I know who has used their services says they wish they had called sooner.  Hospice provides practical and emotional assistance, and they are THE experts in pain management.