Understanding a Suspicious Breast Biopsy: What to Expect

Question
I am a 28 yr. old female, maternal grandma had breast cancer.  After finding a lump, went to gyno, who sent me for mammogram and ultrasound, upon which time the doctor said at my age that it was 95% likely to be a fibroadenoma, but suggested a core needle biopsy.  Despite the fact that three doctors were fairly sure it was a fibroadenoma, it wasn't.  Pathology report is as follows:  Right Breast, 9:00, 4cm from nipple:  Fragments of benign breast tissue with two cores showing changes of complex sclerosing papillomatous lesion of breast with apocrine changes.  The dr. referred to me to a breast surgeon and I have an excisional biopsy surg. scheduled for next week.  It is my understanding that this lesion is classified as high risk, but most of them are benign.  The mass measures 1.2 by .8 cm
My question is; Is there something the doctors aren't telling me because they don't want to unnecessarily frighten me?  How high risk is this?  Is it common for this type of lesion to present on a mammogram/ultrasound as something that appears to be a fibroadenoma?  What does apocrine changes mean?  I realize that every person is an individual, but what are the odds that it is cancer?

Answer
NO, no one is hiding anything for you! Let me clarify one point immediately, what the biopsy of your lesion has shown so far is some BENIGN lesions! You probably have so called sclerosing adenosis. Even with a fine/thin needle aspiration biopsy such a lesion can be tricky to evaluate. But that is not the kind of biopsy you had! It was a so called wide bore core needle biopsy which gives the opportunity of a histopathological evaluation not just a cytological one as in an aspiration biopsy. So this diagnosis is most probably quite certain. If you had had not only mammography and ultrasound breast scans but also an MRI breast scan you very probably could have been told this at once. I agree that a surgical biopsy is OK in order to be completely sure. Apart from the lack of an MRI scan (which may not have been available) your case has been handled absolutely correct so far with mammography & ultrasound followed by a needle biopsy in order to be sure. Milk glands are actually transformed sweat glands. Sweat glands can be differentiated into ecrine glands (that normally do not smell) and apocrine glands (as in armpits) that do smell. Papillomatous lesions (warts) in milk ducts are not uncommon. And apocrine sweat gland like changes in milk glands are not that uncommon either. Such lesions should surely be checked carefully - which is being done - but there is at present no reason for alarm and fear! Good luck!