ovarian tumor with many setums

a tumor 19cm by 18cm by 10 cm was just found on my right ovary. The radioligist said it has many septums in it and I am wondering does that make the chances of it being cancerous higher. I had a ca125 done and it came back 29 which my doctor says is good, but also said they are not always reliable. The tumor does not appear to have invaded any of my other organs yet that they could see on my ct scan. Are there other blood test that I could have to determine if this is cancer or not.