Do Breast Cancer and Prostate Cancer Cluster in Families?

• It has been known for a long time that breast cancers tend to cluster in some families.  With the discovery of the BRCA1 and BRCA2 genes, we have also learned that ovarian cancer is more common in families with breast cancer. Both breast and ovarian cancer are associated with mutations in these two genes.  Now there is mounting evidence that prostate cancer may also be more common in families with breast cancer.

  A recent study from the Women’s Health Initiative found that women who had both breast and prostate cancer in their family were 80% more likely to develop breast cancer themselves than women without such a family history. This association may be due to underlying genetic defects which impact cells in both the breast and the prostate gland.  Some of the association may also be due to shared environmental or hormonal factors.  These findings underscore the importance of learning and documenting as much information as you can about the cancers in your family.

  (The study mentioned above was highlighted in a recent Yahoo! news story)