Still struggling with the word pre-cancer after DCIS mastectomy

I am rather bewildered hearing that women are being told that carcinoma-in-situ is pre-cancer.  It's very name says it's cancer that hasn't gone travelling yet.  Early pre-invasive cancer is really what it is. I understand that it's probably become a way of delivering news so that it doesn't scare the patient too much but it's bloody patronising and clearly incorrect, particularly if it gives a false sense of security.  As @Afraser said, hopefully you come to feel how lucky you have been to get an early warning but to diminish the reality of cancer is to send you back out into life without the understanding of what has happened to your body.  Not that I wish this understanding on anybody but if it's happened, you've got to be aware.