Can endometriosis cause cancer?

No. Endometriosis is not a precancerous condition, although, it does act like a cancer would, though. It may spread around the abdominal cavity, but it doesn't cause death or intoxication like cancer would. It is one of the major causes of infertility and chronic abdominal and/or pelvic pain.
Not known. There appears to be a link between endometriosis and ovarian cancer, but the causal relationship is not established. I wouldn't dwell on the link aspect if you had endometriosis. Obesity, which is a more common problem, is much worse when it comes to cancer link. It's linked with many more forms of cancer, including colon, breast, endometrial, esophageal, pancreatic, gallbladder, kidney, thyroid.