Hi - It means you're pretty much right in the middle as far as "seriousness" goes -many women have less aggressive cancer than you, and many have more serious cases. The easiest way for you to understand all of this is to understand your pathology report, which is where that language comes from. You can download a PDF that'll explain it all in great (and understandable!) detail. Also read our IDC FAQS for more information. And finally, since you're HER2-positive, you'll no doubt be taking Herceptin - so you might as well read up on that, too. Stay in touch here - we can help you through this. Best of luck - PJH