Types of Breast Cancer

I would like to know the different types of breast cancer.  Also, when catagorized, what would a catagory 4 be?  When doing a biopsy and given a greater than 50% chance that it may be cancer, is that good odds?

[CCF-RN,MSN-JS]

Dear Chloe, Breast cancers are generally devided into two types: invasive cancers and noninvasive or in situ cancers.  Invasive cancers are generally divided into lobular (cancers that start in the lobules or sacs in the breast that produce milk) or ductal cancers (cancers that start in the tubes that carry milk from the lobule to the nipple.  Within these broad categories there are over 30 types as seen under the microscope.

I'm not sure what you are referring to in terms of category.  If this is from a mammogram result, category 4, per the Breast Imaging-Reporting and Data System means; there is a suspicious looking abnormality, not characteristic but has reasonable probability of malignancy and a biopsy should be considered.  This data system categorizes on a scale of 1 to 5, with 5 being highly suggestive of malignancy.