4. Histologic Findings In Normal Breast Tissues: Comparison To Reduction Mammaplasty And Benign Breast Disease Tissues

Degnim, A. C., et al., 2012

Before the Susan G. Komen Tissue Bank began collecting “normal” tissue from donors, researchers relied on tissue from a few sources to investigate changes in the breast that lead to cancer. These traditional sources of tissue are from women who undergo reduction mammaplasty; from women with benign breast disease; and, sometimes, from the tissue of women already diagnosed with breast cancer.

But scientists knew they needed a true control group, tissue from women who had had none of these, to really understand the microscopic changes in the breast that lead to disease.

For this study, they used tissue from the KTB as a control to see how the “histologic,” or microscopic properties, compared to the tissue from those traditional sources. If normal tissue looked quite different from that of other sources, they may be able to use that information to figure out what causes normal tissue cells to change.

Methods:

The researchers used KTB samples as well as tissue samples from women who underwent reduction mammaplasty and tissue from women with benign breast disease. In the lab, they looked for proliferative disease and the degree of lobular involution, two key aspects of changes in breast tissue over time. (Proliferative disease means how quickly normal changes in cells occur; lobular involution is how completely the breast changes from milk-producing to weaning, as well as other changes that occur over many years.)

Findings:

The scientist found significant differences in these indicators of changes in the breast.

KTB Samples Mammaplasty Benign

Histologic Changes

(such as lobular involution)

35% 88% 97.5%
Proliferative disease 3.3% 17% 34.9%

 

As you can see in this chart, the “normal” samples from KTB donors showed much fewer incidence in either of the areas the scientists were studying. In the case of lobular involution, samples from the KTB donors showed more complete involution, which has been associated with a reduction in breast cancer risk.

Why this study is important:

Scientists often had used tissue from reduction mammaplasty as a control group, and you can see from the chart why this is not the best strategy. Normal breast tissue has very different properties, which can help us understand better how changes in the breast set up conditions that allow for breast cancer or other disease to develop. KTB donors provide scientists with a unique and needed resource to pursue research that sheds light on development of breast cancer.