ca 15.3....what the heck??

Hi again to all,

Well, i have currently finished chemo which was in September, then had radiotherapy which finiished in October all of which went really well. I didnt suffer with either. I’m now on herceptin for a year. I was diagnosed in April this year, with grade 3, stage 3a, ER- and her2+. I had a WLE so surgery was also a success…Had a CT scan because i had node involvement and that was clear. Anyway basically everything seems to be going really well so far. I have had regular blood tests and have all come back clear.
I went to see my oncologist today and he examined me and said everything is fine. He looked at my notes and also said excellent. However he has requested for me to have a blood test and when i looked at the form it said full blood count, also ca15.3.I have googled it and it says ca15.3 means tumor markers. This has made me feel a bit stressed tbh. I am now worrying that they must be looking to see if i’ve got secondary cancer.I have been extremely positive so far but this has scared me a bit. Is it normal to have these blood tests? do they look for tumor markers everythime we have blood tests done?.Hope someone can enlighten me…

Karen xx

HI Karen
I don’t know the answer but someone else may. Perhaps your breast care nurse would know. The rest of your recovery thus far sounds very postive.
Hope you get some answers soon

Hi,Thanks toriaconey, it seems not many people know what it is. I wished id not looked at the form now. This breast cancer stuff is certainly a journey…xx

Ca 15.3 is a tumour marker that looks at tumour activity. Its reliability varies from person to person. #when you have a primary tumour the level is usually but not always raised. treatrment should bring the level down. Similarly in someone with secondary cancer it can help monitor how much a treatment is helping. The actual level can vary from person to person. i would guess your onc is just checking what a “normal” level is for you. If you then go back complaining of any symptoms he could check it again and get an indication if your symptoms are anything to do with a recurrence. Take care Pamx

Hi Karen I am ER/PR+, HER-, grade 2, stage 2b with lymph node involvement. I was dx July 2012 and had chemo first. My WLE is scheduled for next week and then I will have rads. Please don’t worry about tumor markers ca153. I had them regularly checked as well as ca125 whilst going thru chemo. It’s another tool the docs can use to assess your treatment, but nor reliable taken on their own - other things can raise your levels and you may not have a raised level if u have cancer. Good luck with the rest of your treatment. X

i meant the onc said i didnt have to have the blood test straight away so it cant be that urgent. xx

Thankyou herbgarden and spookymoo, youve both eased my mind a little. Do the drs normally check for tumor markers with every blood test then? is it a standard thing? i wouldnt have known if i hadnt seen it on my form for the blood test. The onc saod i didnt have the blood test straight away but i had it done just to get it over with xx

arghh my comment number 6 should have been under comment 7 lol

Hi karen

My surgeon uses this tumour marker on me regularly, in fact while I was having chemo my tumour marker went from 16 to 31 which is over normal, this frightened the life out of me as I really thought the cancer was spreading. Two months later the marker returned to normal. My oncologist won’t use them as he says they are unreliable and all sorts of conditions can elevate the reading. he says he like to go on how well his patients feel, as routine blood testing and scans cause so much anxiety. Try not to worry. by the way love the new hair, its given me the incentive to dye mine (looks like a Brillo pad at the moment)! michelle xx

Hi Michelle,how are you keeping? its lovely to hear from you btw. Thanks for your feedback. This ca thing scared me tbh. Its all scary at times isnt it?..Thanks for saying you like my hair.Mine too was like a brillo pad ha ha…I will grow it though has i dont like short hair.xxxx

Karen, have sent you pm. Michelle xx

cheers mate xx

not many replies on this subject… then??

Do the Drs have to inform you that they are doing this CA15.3 test? I dont know whether they have been doing this test every time i’ve been having blood tests and why bother having CT scans if they can check with a simple blood test to see if there is any activity going on in our bodies?? Also if the reading is abnormal would they have told me by now?..

karen xx

Hi KB, I think it varies from hospital to hospital, and from onc to onc if they use tumour markers or not. As someone said in an earlier post it is possible your onc has taken it this time so that if they want to come back to it further down the line they have something to compare with. I think it is probable that your hospital/onc does this blood test at intervals, not necessarily every time blood tests are done. As to why do they bother with CT scans if they can tell there are problems just with a simple blood test - all these things are just one in a whole range of tests that give our oncs clues as to whether something is going on in our bodies that needs further investigation - they all build up a picture. It is always stressful when we are having any sort of tests, but you should never feel bad to ask your onc why they are doing any specific test.


Hi KB, I have tumour markers done every clinic appointment to see my onc, it’s 2 years since my diagnosis. Onc orders ca15-3 and ca125 every 3-4 months when i get to see her, aswell as the usual full blood count. Thus i think it depends on your individual onc’s preference.

Hi Karen
Don’t worry…I was diagnosed in 2008 and at my 6 month oncologist appointment I have ca15-3 & ca125 . I am treated at Royal Marsden, Chelsea.
Bethy x

Thank you so very much for your responces ladies.
I was going to phone my bc nurse today to find out what the results are, but im sure that if there was anything worrying then they’d have let me know by now. I thought that having a CT scan was enough,I also thought that the next step after treatments are finished was just self examinations and mammograms. Nobody has mentioned anything about these tumor marker tests.I dont like this test because it is making me very uneasy and im worrying about recurrances and secondary cancer. I have got my Herceptin on the 1st of Feb so i’ll ask them the results then.

Karen xx

I think im getting stressed over nothing tbh…xxxx

Also i was told that this test is so that the dr can check to see if all the cancer has gone so they can then tell you that you have got the all clear…