Biopsy for every new met?

Hey! This is my first post so I’m not sure how it works… 

My Mum has been living with secondary breast cancer since 2019 following the discovery of two brain tumours. Yesterday we got told after a year of NED she has new mets in her lungs. She starts Kadcyla next week. 

Her primary cancer was HER2+ and ER+ as was her brain tumours. Should we be having a biopsy with every new met to see if this changes? 

A biopsy has not been mentioned but I am concerned she should have one… 

Thanks! 

Hi Zoe

I’m so sorry you and your mum are in this situation. I wonder if this isn’t a question better asked of your mum’s oncologist as s/he will have all the specific details of your mum’s cancer. One thing I’ve learnt in the last 20 months is that each cancer is incredibly complex - and unique. Her breast care nurse might be a good point of contact or her oncologist’s secretary.

What does your mum think herself? This is her condition and it’s great that she has family support but ultimately she has to be the one taking the decisions. She may prefer, like me, to know as little as possible and trust her team to do their best for her. On the other hand, this might not be something that’s occurred to her as an option and a conversation is needed. Her choice must always be respected even if you don’t think it’s the right choice. Sorry, I’m not suggesting you are interfering. I really think your mum is lucky to have you on her side but this may be a case of you feeling that, armed with more knowledge, you can support your mum in getting the best treatment while she may feel she just wants to get on with it.

My personal experience would suggest that many oncologists try to avoid invasive treatments like surgery at Stage 4 as the risks can outweigh the benefits. There will be a MDT (multi-disciplinary team) deciding on the treatment plan and it may well be that they believe that the chemotherapy will attack the new mets regardless of their hormone-receptive composition. 

I wish your mum all the best with her new treatment. It’s never easy having settled into feeling everything is going smoothly to suddenly realise the cancer is on the move again xx