Liz, best of luck, and I can only imagine how you must have felt when you read those words.
I used to do a fair amount of medical negligence work, usually representing the doctor. (Keep in mind I am in the US, so my comments may not apply to your situation). Cancer cases used to be deemed very difficult ones as a whole, due to the need to prove that it was more probable than not that a different (and better) outcome would have resulted had the diagnosis been made in a more timely fashion. However, as the concept of some cancers as a chronic illness has taken root, palliative care has emerged as its own specialty, and overall treatment courses have radically improved, these cases have been viewed more favorably, as earlier diagnosis almost invariably results in a longer period of quality life, regardless of ultimate outcome.
Our thoughts and prayers are with you.