Atypical hyperplasias

(pathology findings explained)

Sometimes, when a breast biopsy comes back, it shows cells that the pathologist classifies as “atypical”. This finding can be confusing and anxiety provoking to the patient. Any time atypia is seen on a biopsy, it does warrant a consultation with a breast surgeon.


Atypical Ductal Hyperplasia

Atypical Ductal Hyperplasia, often abbreviated as ADH, is not a breast cancer. It does, however, indicate that the patient is at increased risk for the future development of breast cancer. We also know that when ADH is found during a core biopsy, the core biopsy may underrepresent the full extent of the disease present. It is indicated to go and do a wider excision to make sure there is no pre-invasive or invasive breast cancer associated with the atypical ductal hyperplasia.


Risk Management

Once we have established that there are no additional worrisome lesions associated with the ADH, then the conversation turns to risk management. There are many options for managing risk in patients with ADH. One may wish to change the frequency of or add other modalities such as MRI to their breast cancer screening regimen. Life style modifications are always important. Breast cancer risk reduction medications are particularly useful in this group of patients.

Medication Options
Tamoxifen has been shown to decrease the risk of breast cancer by about 50%. However, in the subset of patients who had ADH, Tamoxifen was even more effective. Aromatase Inhibitors are another option for breast cancer risk reduction but only in post-menopausal women. There are other forms of atypia that can show up on a biopsy report including atypical lobular hyperplasia, flat epithelial atypia and columnar cell change with atypia. All seem to increase the future risk of getting breast cancer.