New Findings Contradict Current Understanding of How to Manage Breast Biopsy Abnormalities
A long-term follow-up study by Hartmann et al of patients with two types of breast tissue abnormalities—atypical ductal hyperplasia and atypical lobular hyperplasia—suggests that both abnormalities have the same potential to advance to breast cancer. The findings could help improve clinical management of patients with these breast tissue abnormalities. The study is published in Cancer Prevention Research.
The study results challenge current understanding that atypical ductal hyperplasia leads to breast cancer in the same breast, while atypical lobular hyperplasia may not be a direct precursor of breast cancer but may indicate equal risk of breast cancer across both breasts.
Study Methods and Results
Using the Mayo Benign Breast Disease Cohort, the researchers identified 698 women who had biopsy-confirmed atypia and followed them for an average of 12.5 years. Three hundred and thirty women had atypical ductal hyperplasia, 327 had atypical lobular hyperplasia, and 32 women had both types; 143 of the women developed breast cancer.
The researchers found that for both atypical ductal hyperplasia and atypical lobular hyperplasia, the ratio of breast cancer in the same breast in which the atypia was detected vs in the opposite breast was the same: 2:1. A similar number of women with either atypical ductal hyperplasia or atypical lobular hyperplasia developed breast cancer in the same breast within 5 years of diagnosis, suggesting that like atypical ductal hyperplasia, atypical lobular hyperplasia may also be a precursor in addition to being a risk indicator.
Contrary to current understanding that atypical lobular hyperplasia mostly leads to the development of lobular cancer, the investigators found that atypical lobular hyperplasia predominantly resulted in ductal cancer of the breast, an outcome similar to that seen with atypical ductal hyperplasia. Both types of atypia resulted in invasive ductal cancers, of which 69% were of intermediate or high grade. About 25% of them had spread to the lymph nodes. The pattern of cancers in these women resembled those seen in the general population.
“In our view, [atypical lobular hyperplasia] and [atypical ductal hyperplasia] both represent important premalignant entities,” wrote the study authors. “Better understanding of the natural history of atypical hyperplasia, ductal, and lobular, will advance both our understanding of breast carcinogenesis and our clinical management of these high-risk patients.”
Developing Better Clinical Management Strategies
“If a woman has a breast biopsy and if it shows atypia, it might be wise for her to be seen at a breast center for recommendations about surveillance and preventive therapy options,” Lynn C. Hartmann, MD, Professor of Oncology at the Mayo Clinic in Rochester, Minnesota, and lead author of the study, said in a statement. “We hope these data will further help clinicians make informed decisions for breast atypia management strategies.”
Dr. Hartmann is the corresponding author for the Cancer Prevention Research article.
Study author Richard J. Santen, MD, has a commercial research grant from Pfizer and is a consultant/advisory board member of Pfizer. The other study authors reported no potential conflicts of interest.
This study was funded by the Mayo Clinic Breast Cancer Specialized Program of Research Excellence (SPORE) grant from the National Institutes of Health and Susan G. Komen.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
