CA125 Test Level 1400, 10-12cm Ovarian Cyst, 66 Yr. Old Woman?

My mom had a hysterectomy right after I was born in '76, but they left her ovaries. She recently had her yearly check-up at the gynecologist who informed her she had a large, solid m on her ovary of approximately 10-12cm that is not attached to her bladder or intestines. She had a CA125 Test and her level was 1400. She will be going to the M.D. Anderson Cancer Center in Houston, Texas to see Dr. Ramirez on Thursday and have this cyst removed on Monday. From what I have researched, this isn't good, but until they remove the cyst, we don't know the exact prognosis. I am uming with such high levels this definitely has to be malignant and she probably has Ovarian Cancer. I am just beside myself with worry. This is my mom. I only have one mom. She lives in NY and I live in CA. She doesn't want me to come out to Texas for the surgery because she wants me to stay with my daughters ages 3 and 7 to comfort them. But, what if it is the last time? I need help understanding what is going on.