(CNN)Geto Boys co-founder Bushwick Bill is battling stage stage 4 pancreatic cancer .
Bill told TMZ that he was diagnosed in February.
He said that he has been undergoing chemotherapy, but his prognosis is unclear.
"And I was like, stage 4? I have been getting tested for a mass but it was benign," Bill told TMZ. "So, I am like could it be cancer? I was told it is mass with no purpose. So to find out, and pancreatic cancer is undetected until it's in the fourth or fifth stage."