I wouldn't think that if the mass were something that could recur that your Dr. was thinking "cancer". Fibroadenomas when removed or not don't exactly recur but more may develop. I don't quite "get" the term borderline unless it might be a Lipoma (fatty tumor) or a type of cyst that wasn't entirely filled with fluid but some solid material. It really isn't all that unusual to have specimens sent to another Lab though ... and it would be VERY rare to have found a cancerous tumor as large as you mentioned unless you had it for a few years. Regards ...
Hi,
Another possibility might be that your doctor is trying to make sure whether it is a fibroadenoma or a phyllodes tumor, which often appears similar to a fibroadenoma.
Here is some information about phyllodes tumors:
"Phyllodes tumors are rare solid lumps that usually present as a mass found during a woman’s breast self-examination or on a routine physical examination. Smaller masses may be detected mammographically. Phyllodes tumors appear very similar to a benign lump known as a fibroadenoma. These lumps are usually well circumscribed and painless. Imaging evaluation including a mammogram and ultrasound is usually performed and when a solid lump is identified a biopsy is important to obtain tissue for accurate diagnosis. A phyllodes tumor cannot be differentiated from a fibroadenoma by a needle biopsy. This means that your doctor may not be able to accurately tell you whether a solid lump is a benign fibroadenoma or a phyllodes tumor. Risk factors for phyllodes tumor are rapid growth and size greater than 2 cms at the time of the evaluation. In many cases your doctor may recommend complete surgical removal of this mass to ensure that it is not an underlying phyllodes tumor.
Phyllodes tumors are not all cancerous. Many will be classified as benign and not require further evaluation. A skilled pathologist is needed to distinguish a benign phyllodes tumor from one with more aggressive malignant potential. In any event, women who undergo surgery for removal of a phyllodes tumor require close surveillance with followup mammogram and physical examination at regular intervals. Malignant phyllodes tumors are best managed with a wide excision of normal breast tissue around the tumor to obtain clean margins. In most cases, radiation therapy is not required. Very large malignant phyllodes tumors may require complete removal of the breast for management."
Best wishes,
bluebutterfly