Dense Breasts Linked to Breast Cancer Return

Study Shows Dense Breast Tissue May Raise Risk for Cancer Recurrence in Other Breast
Women with an early form of breast cancer are at higher risk for recurrence if their breast tissue appears dense on mammograms, a study shows.
The study also shows the risk of recurrence is more pronounced in the opposing breast.
In the study, of 935 women with an early type of breast cancer known as ductal carcinoma in situ (DCIS) treated with breast-conserving surgery, those women whose breasts appeared dense on their screening mammogram were twice as likely to develop a secondary breast cancer. This risk was about threefold higher for developing a secondary breast cancer in the opposite breast, the study shows.
DCIS refers to breast cancer that has not spread outside the milk glands. During follow-up, 164 had a subsequent breast cancer on the same breast and 59 developed a new cancer in the other breast.
Composed of breast ducts and connective tissue, dense breast tissue looks white on mammograms. Non-dense breast tissue is mainly fat and appears dark gray on a mammogram.
Exactly how dense breast tissue increases breast cancer risk is not fully understood, but breast density may be mediated by certain hormonal and genetic factors. That said, certain hormone therapies can increase or decrease breast density and should be discussed with a doctor if a woman has dense breasts.
According to the National Cancer Institute, women who have a high percentage of dense breast tissue have a higher risk of breast cancer compared to those of a similar age who have a small percentage of or no dense breast tissue.

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