Hi all - the CA 27-29 question was posted back in 2019 but still always relevant. This reply is lengthy but you will see why. I am MBC patient diagnosed in 2019 - did double mastectomy - knew that it was in my breast lymph nodes but found by my dermatologist in my skin. (Also tested positive for Lyme at same time). So didn't do radiation nor chemo but went straight to Verzenio & Armidex. My team was very clear to me that they were going to use 4 indicators to track my cancer - scans, bloodwork, skin changes & my physical well-being. Re bloodwork - couple of choices - CEA, CA 125 & CA 27.29. We did a baseline of all 3 & quickly determined that the 27.29 was my best indicator. (others were all normal) A little after my surgery but before I started my meds CA 27.29 was 59. That was above the range but some of you know that number can be much higher. A month after I started my meds it started dropping and held steady around between 14 & 28. Yes there was fluctuation but my doc always told me never worry about just one test - inflammation, bad blood draw, test issues, etc can affect a reading. He wanted a trend. Fast forward to April of 2021. My number came in at 58. Damn. Told to sit tight, but was feeling a little off (back, knee, kinda moving around) that was the physical. No skin issues. My May test comes in at a lower 52, then June 31, then a 40. But I developed other physical issues. Ascites mostly. Did scan which showed issues and did CA 125 bloodwork which jumped from 8 to 703. Breast cancer had spread to my Peritoneum & Omentum, (Not Ovarian). So my meds stopped working. Fast. New meds did not work. We pivoted to my 1st chemo infusion treatments of Taxol & Avastin, and Fulvestant butt shots in mid-June. 20 weekly Taxol just finished, maintenance will be the Avastin infusion every 3 weeks and monthly shots. Ca 27.29 has been tracking below 20 and my CA 125 now 8. Scans are clear. So - I share this story for a couple of reasons. 1st - I track my bloodwork. I do it on an Excel spreadsheet but a piece of paper works fine. Every test, every time. Starting it & filling in the old data is time consuming but I see my results and my trends. I am not going to rely on overworked docs and nurses. It lets me control something. I can see for myself what my 'normal' is and peoples numbers can be different. You can ask for other bloodwork to find your baseline. Keep copies of your reports on your scans. 2nd - numbers do fluctuate so don't panic. 3rd - assess everything else - physical and scans. 4th - stay in touch with your medical team. Work the emails and the phones. A nice squeaky wheel - talk to them about the right amount of time between tests, assessments, etc. I have made it very clear to my team that keeping me alive is a "success" or "challenge" - I will do the things I want to do - and I will be totally difficult if they don't take that seriously. Fingers crossed & prayers for all!!