When your breast was biopsied, the samples taken were studied under the microscope by a specialized doctor with many years of training called a pathologist. The pathologist sends your doctor a report that gives a diagnosis for each sample taken. Information in this report will be used to help manage your care. The questions and answers that follow are meant to help you understand medical language you might find in the pathology report from a breast biopsy, such as a needle biopsy or an excision biopsy.
In a needle biopsy, a hollow needle is used to remove a sample of an abnormal area. An excision biopsy removes the entire abnormal area, often with some of the surrounding normal tissue. An excision biopsy is much like a type of breast-conserving surgery called a lumpectomy.
All of these are terms that describe benign (non-cancerous) changes that the pathologist might see under the microscope. They do not need to be treated. They are of no concern when found along with cancer. More information about many of these can be found in Non-Cancerous Breast Conditions.
Fat necrosis is a benign condition that is not linked to cancer risk. It is most often caused by trauma (injury) to the breast, although it may also be seen without any history of trauma.
UDH is a benign finding that is linked with a slight increase in getting breast cancer in the future. It does not need to be completely removed or otherwise treated.
These findings are benign (non-cancerous). If these findings are seen in an excision biopsy, no further action is needed. However, if they are found on a needle biopsy, it isn’t so simple. If the lesion is small, entirely removed by the needle biopsy, or unrelated to what was seen on the mammogram, then no further treatment may be needed. However, for lesions that are larger or not entirely removed by the needle biopsy, more tissue from that area may need to be removed because sometimes they are found near something more serious that may need to be treated. You should talk with your doctor about what is best in your case.
A papilloma is a type of benign (non-cancerous) growth. If a papilloma is found on an excision biopsy, no further treatment is usually needed. When a papilloma is diagnosed on needle biopsy, it isn’t so simple. If the papilloma is small and what was seen on the mammogram looked like a papilloma (and not something more serious), no further treatment may be needed. Often, however, the doctor may recommend removing more tissue in the area to be sure there isn’t anything more serious nearby. You should talk with your doctor about what is best in your case.
Flat epithelial atypia is not cancer. Sometimes, though, it is found near something more serious. If flat epithelial atypia is found in an excision biopsy, most often no further action is needed. However, if flat epithelial atypia is seen on a needle biopsy, your doctor may recommend that some of the tissue around the biopsy site be removed (surgical excision). Still, the best way to treat flat epithelial atypia is not clear. If your biopsy showed flat epithelial atypia, the best thing to do is to talk with your doctor about it.
Fibroadenoma is the most common benign (non-cancerous) tumor in the breast. If it is diagnosed on needle biopsy and what was seen on the mammogram looked like a fibroadenoma (and not something more serious), it doesn’t need to be removed and can be watched without further treatment. If the tumor is growing or causing problems with the way the breast looks, it may be removed.
A phyllodes tumor is a very rare breast tumor that develops from the cells in the stroma (connective tissue) of the breast. Other names for these tumors include phylloides tumor and cystosarcoma phyllodes. These tumors are usually benign, but they can come back and cause the breast to look abnormal if not totally removed. On rare occasions they may be malignant (a cancer). Malignant phyllodes tumors can spread beyond the breast, although this happens less often than with more common types of breast cancer. If a phyllodes tumor is diagnosed on needle biopsy, it is most often treated by removing it completely (often with some type of breast-conserving surgery).
In some cases it might be difficult for a pathologist looking at a needle biopsy to tell for sure if the growth (tumor) is a fibroadenoma (a common benign tumor) or a phyllodes tumor. In that case, the pathologist may call it a cellular fibroepithelial lesion or a benign fibroepithelial neoplasm. Because it could be a phyllodes tumor, the tumor is most often treated by removing it completely (often with some type breast-conserving surgery, such as lumpectomy).
Microcalcifications or calcifications are calcium deposits that can be found in both non-cancerous and cancerous breast lesions. They can be seen both on mammograms and under the microscope. Certain types of calcifications are found in areas containing cancer. If these are seen on a mammogram, that area may need to be biopsied. Then, when the biopsy is done, the pathologist looks at the tissue removed to be sure that it contains calcifications. If the calcifications are there, the doctor knows that the biopsy sampled the correct area (the abnormal area with calcifications that was seen on the mammogram).
These are special tests that the pathologist sometimes uses to help make the correct diagnosis of a variety of breast lesions. Not all patients need these special tests. Whether or not your report mentions these tests has no bearing on the accuracy of your diagnosis.
This series of Frequently Asked Questions (FAQs) was developed by the Association of Directors of Anatomic and Surgical Pathology to help patients and their families better understand what their pathology report means. These FAQs have been endorsed by the College of American Pathologists (CAP) and reviewed by the American Cancer Society.
Last Revised: August 6, 2020
Copyright 2017 Association of Directors of Anatomic and Surgical Pathology, adapted with permission by the American Cancer Society.