Stilly asks: "Do mammograms show this at all?"
The answer seems to be "no", from what I've gathered so far. But thanks for the pix, SRS. They're much more comprehensive than what I'd found (why didn't I think of searching Google for images?!).

I notice on your link that the Inflammatory Breast Cancer Research Foundation has a logo with what almost looks like one-half of the ubiquitous "ribbon" (if it were cut lengthwise), in red. The Foundation's site has a lot more info about IBC, including the following statistics: "African Americans have a higher incidence of IBC than do Caucasians and other ethnic groups (10.1%, 6.2%, and 5.1%, respectively)... Age 52 [is the] median age at time of diagnosis of IBC versus age 62: median age at time of diagnosis of [other forms of] breast cancer." Here's a link to http://www.ibcresearch.org/