There is no given life expectancy. Stats say there is 80 % survival rate after 5 years and many go into remission for years. Again every case is different and of course getting an early diagnosis is key for sure. If one follows the required treatment prognosis is very good.
Some complication such as severe kidney damage , bowel obstruction,which is what I had or it killed part of my bowel, anyerusum or heart failure are some of the more severe issues that can occur. Again it's all about early detection in most cases.