Increased density of breasts

I had pain in my left breast and went to my midwife. She said she could feel a lump and sent me for mammogram and ultrasound. I'm 38 yrs old, have 2 kids and nursed my first one for 13 months and second for 2 years. The mammogram was compared to a baseline study done 3 years ago.

The mammogram and sonogram results say:
"1. Irregular increase in density in the breasts bilaterally most focal in the superior breast and right periareolar region. This shows no sonographic correlate and merits further evaluation by MRI to exclude an infiltrate or neoplastic process.
2. A 1.1x0.5x0.4 complex cyst or solid mass at the 2:00 position of the left breast in the area of clinical concern meriting aspiration or biopsy.
Birads 4-suspicious abnormality.

There has been a significant increase in the density of the breasts bilaterally predominantly supriorly but also in the right inferior periareolar region. On the right mediolateral oblique view, this appears to have associated architectural distortion. On the spot compression views, the area of density appear to disperse somewhat appearing slightly less masslike. On the 90-degree lateral projection shows persistence of an irregular density in the retroareolar region as well as an inferior right reast. No discrete mass is identified to correpond to the masslike areas of irregular and icreased density in the superior breast bilaterally. These areas merits further evaluation by MRI.

In the area of palpabal concern, there is a complex hypoechoic mass or cluster of complex cysts measuring, in aggregate, 1.1x0.5x0.4 cm. This merits surgical consultation for the purposes of aspiration or biopsy."

Can someone please tell me what are the chances of my having cancer? I'm going for MRI in 2 days.

Thanks.

[Cleveland Clinic]

Dear vp_nm:  The only thing these tests show is areas of abnormality that indicate further investigation.  There is no way from this information that we could estimate the risk of this being malignant.