Cancer metastatis to liver and bone. Stage IV. What is her life expectancy now ?

My aunt had one removed surgically in 2008 for cancer. Radiotherapy was done but no chemo as she had no one to take care of if chemo undertaken. Now aged 66 yrs. Last month, it is learnt that it has metastatized to liver and bone. Now on Tab Tamoxifen and still not ready for chemo. Has had early menopause around 37 yrs of age. Friends from medical line please advise about how long she can go without chemo and how this condition will affect her physically ? Thanks a lot.