I was diagnosed with TNBC in 2013 and thankfully the TNBC has not come back. I did have a recurrence in 2019 of two new breast cancers: HER2+ and also ER+PR+. They say bad things come in 3s, so I'm hoping this is the end of my cancer journey...

I recently had a second opinion from a breast cancer specialist around prevention and monitoring and he suggested that I monitor 6-monthly with a CA15-3 test. I was wondering if anyone has experience with this. My first oncologist said it was a waste of time because there's nothing I can do if it comes back. Any thoughts??
Thanks
Liz