A new study, based on 78,171 women who had been examined in the Women’s Health Initiative Observational Study between 1993 and 1998, and whose evolution was traced until 2009, revealed that women who come from families with a medical history of prostate cancer or breast cancer have increased rates of breast cancer. While the fact that having relatives with breast cancer increases a woman’s risks of developing the disease herself was widely-accepted knowledge, the connection between male relatives with prostate cancer and the occurrence of breast cancer in women is a new finding. The research team who conducted the study has published the results online, yesterday, March 9, in the medical journal Cancer.
Researcher Jennifer Beebe-Dimmer, from the Barbara Ann Karmanos Cancer Institute, affiliated with Wayne State University in Detroit, was part of this research team. She wrote that women who have first degree relatives (fathers, brothers or sons) suffering from prostate cancer are have the most significant risks – their chances of developing breast cancer are estimated at 14%. Women with family histories including cases of prostate and breast cancer face an overall probability of developing mammary malignancies 78% larger than women without family antecedents. What the study discovered is not a causal relation, but a statistical correlation. The explanation for the link between family breast cancer and a patient’s developing the disease is that mutations in the BRCA1 or BRCA 2 genes (the most common causes of hereditary breast cancer) can be transmitted from mother or father to child. As for the prostate cancer-breast cancer connection, Dr. Beebe-Dimmer claims that very little is known so far about its underlying causes.
The importance of this discovery, the doctor added, is that it sets clinicians on a quest for understanding the clustering of tumors in families, which might yield results that are relevant for tracing genetic mutations. In order to gather more data, Jennifer Beebe-Dimmer advised doctors to collect a complete family history of all cancers (most importantly among first degree relatives). The study is an important milestone in cancer-related research because it was conducted on a large population of women, which makes the estimations more precise. Its only weakness is having relied on self-reported family histories of cancer occurrences, but given that first-degree relative cancers are the most important factor, the chances of significant omissions are low.
image source: The Nature’s Farmacy