Mri detecting high grade dcis

I am up late, and decided to do a little research on mri's and dcis. I found the following article intriguing, which put forth a question on high grade dcis. According to an ariticle I read, high grade dcis shows itself differently on an mri than low grade dcis. The article I read said it is detected because it has begun to develop its own blood supply...vessels. I thought all dcis was completely contain in the ducts and had no blood supply.

Below, is part of the article I read.

The interesting feature of our data is that, very unexpectedly, MRI has proved not only on a level with mammography in the detection of in-situ carcinomas but, in fact,  significantly superior - particularly in the diagnosis of high-grade in-situ carcinoma. In the detection of 167 in-situ carcinomas the sensitivity of mammography was 51%, MRI was 92% - figures that are clearly in favour of MRI. Mammography was particularly insufficient to diagnose high-grade in-situ carcinomas: it could not detect over half of the high-grade DCIS - because they had not developed any calcifications!
‘It appears that a relevantly high proportion of the in-situ carcinoma does not calcify, so mammography cannot detect it. I said earlier that 20% of all diagnosed carcinoma are in-situ carcinomas. But we know that almost all carcinomas go through this stage - so what happens with the rest? We must assume that MRI will enable us to detect more carcinomas at this early stage, particularly the high-grade carcinoma.

‘Basically, unlike what was previously believed, MRI is superior to mammography also for the pre-invasive stages, the in-situ carcinoma. For the non high-grade in-situ carcinoma both procedures are complementary. For the high-grade in-situ carcinoma they are not complementary - MRI is clearly superior.

‘One of my favourite assumptions (but which cannot be proved) is that the perhaps 10% of DCIS that cannot be detected by MRI are not biologically relevant - because they are not preparing to invade and might never become invasive. For invasive growth, the DCIS requires vessels that deliver nutrients and oxygen. When those vessels are present MRI can detect the DCIS, so quite possibly we can see all those carcinomas that are preparing to invade. If we want to detect breast cancer at an early stage then, quite clearly, we want to detect it at the in-situ and early invasive stages. And we certainly want to find the high-grade carcinomas. If we know that the examination we currently use for early detection - mammography -  can only find half of the invasive and intra-ductal carcinomas, then the logical consequence is obvious.

*Dr Kuhl is Professor of Radiology and Vice Chair at the Department of Radiology, and Director of the Division of Oncologic Imaging and Interventional Therapy at the University of Bonn.