Well, CA125 is a protein that shows up in the blood and is considered merely a 'cancer antigen marker'. In other words, you could have a high level and have no cancer, or have a low level and have cancer, and every scenario in between. As you've probably read, there are women who have had numbers into the hundreds and have been NED (no evidence of disease). And while many of us aspire to reach the lowest number possible, some women have had levels of 5 or 6 and have had cancer. The bottom line is that each individual situation is different.
When this all first started for me, the range that most doctors and labs used was 0-35. Now it has changed (at least at my lab) to 0-21. For example, if you are having problems and your level is maybe around 19 or 20, the doctor may order additional tests to rule out any potential problems. As time goes on, they will take this test routinely to watch for a rise in numbers to again alert them to possible problems. Now you have a general idea of what is 'normal' for you and you can use this test in conjunction with other tests to be watchful.
The unreliable part about this test is that the CA125 can rise for a number of reasons. When I was diagnosed I had no symptoms at all, just a extended stomache. My doctor gynecologist ordered a CA125 test which I wasn't even aware was included in the blood work, until he called me one night. It was 13,000, well over the 0-35 range. However, I had a hysterectomy in 1991 my ovaries were left, in February of 2008 I had surgery and the removal of my ovaries , also all the fluid was drained which came back positive for ovarian cancer.Since then, I had my CA125 tests monthly, then every other month, etc. After surgery, chemo, etc., I found my 'normal' range. So for me, the numbers are a big help to at least give us some feedback. I will say, however, that it will go up from stress, infections, inflammation, etc. But it's the consistent rise in numbers that alerts us that something may be going on.
Well, I know this was lengthy, but I hope this helped you understand what it's all about. You can also Google 'CA125' and you will get more information.
Let us know how you are doing, and maybe share what you've been through with us. We like to toss ideas back and forth, share thoughts, and mostly there are tons of shoulders to lean on here.
Have a wonderful day!
Terry