Outcomes of breast cancer may be inherited
NEW YORK (Reuters Health) - A woman's likelihood of surviving breast cancer is related to the survival rates among her first degree relatives with breast cancer, according to a new report.
"If the association turns out to be true ... it will open a new field for prognostication," Dr. Mikael Hartman from the Karolinska Institute, Stockholm, told Reuters Health.
Hartman and colleagues analyzed breast cancer prognosis among 2787 mother-daughter pairs and 831 sister pairs who had breast cancer diagnosed between 1961 and 2001.
The survival rate at 5 years for daughters whose mothers died within 5 years of diagnosis was 87 percent, compared with 91 percent for daughters whose mothers were alive 5 years after diagnosis, the team reports in the journal Breast Cancer Research.
The difference was greater for daughters whose mothers were younger than 70 years at diagnosis (83 percent versus 90 percent), the report indicates, and the difference for sisters was even more marked (70 percent versus 88 percent).
"So far, we can say ... that the simple question 'Did your mother die of breast cancer within 5 years?' can differentiate women into low and high risk groups," Hartman said.
"The difficult part is now to identify what is actually inherited," Hartman commented. It could be that women inherit some tumor characteristic or a particular aspect of the immune system. "It may simply turn out that some individuals are better or worse at fighting off tumors."
SOURCE: Breast Cancer Research, June 28, 2007.
What breastcancer.org says about this article…
Outcomes of breast cancer may be inherited
The study reviewed here showed that the length of time a woman survives after a breast cancer diagnosis is related to how long any of her first-degree relatives survived after breast cancer. For example, if her mother or sister lived for more than 5 years after diagnosis, then a woman also tended to live more than 5 years after her own diagnosis. This link appears stronger between sisters than between mothers and daughters. But the mother-daughter link was stronger when the mother was diagnosed before she was 70.
Research has shown that genetic differences are probably why breast cancer risk, response to treatment, and prognosis are different for all women and different among ethnic groups. In this study, genetic differences are probably why first-degree relatives have similar survival times. Unfortunately, there's still much more research to be done to understand exactly which genes are involved and how these genes affect prognosis. In the meantime, if you've been diagnosed with breast cancer and have a first-degree relative with breast cancer, discuss this information with your doctor. This family history might be important when you and your doctor decide on the best treatment plan for YOU.
