Hi @templar-1310 you are all in the worst phase at the moment, in that information is still being gathered and there will be a period of waiting for test results to go back to the Mixed Disciplinary Team (MDT) who then make a diagnosis and design a treatment plan which is specific to your daughter. It is understandable - and common - for us all to fill in the gaps that we don’t yet know with worst case scenarios. Once you know the factual diagnosis and the treatment plan, the mind can turn to positivity and taking the required steps to treat the cancer.
She is very young to be facing this challenge but with the right support and belief, the chances are she will come out the other side and go on to live a normal life. The treatments can be harsh however so hearing from those who have been where she is now will help. I have put a link below to a forum thread for young women which might be helpful.
If she is indeed HER2+ then this thread will allow her to interact with others who have had the specialist targeted treatment HER2+ and need some buddies
I know you are very busy at the moment so no need to reply but I hope these links will be useful (just click the pink links)and I send every good wish to you and your extended family for a successful conclusion to this unwelcome challenge.