FRIDAY, Oct. 16, 2009 (HealthDay News) -- Women with a high genetic risk of developing breast cancer are being diagnosed sooner than similar women in the past, which may suggest that tumors are developing earlier in the younger generation, researchers say.
The finding, presented at the 2009 Breast Cancer Symposium, held last week in San Francisco, could potentially affect how women are screened for breast cancer.
About 5 percent to 10 percent of breast cancer cases are thought to be connected to a genetic mutation that's also linked to ovarian cancer. Women with the mutations, known as BRCA1 or BRCA2, have an increased risk of developing breast tumors. Over a lifetime, 60 percent of them will develop the disease, according to the American Cancer Society. By comparison, 12 percent of women in the general population will develop breast cancer.
Women who have the genetic mutation -- or whose mothers or aunts have it -- are advised to be screened for breast cancer starting when they are 25. Mammography and MRI are now recommended for these women.
In the new study, the researchers examined the medical records of 132 women with the genetic mutation who took part in the University of Texas M.D. Anderson Cancer Center's clinical cancer genetics program between 2003 and 2009. Of those, 107 had a mother or aunt with breast or ovarian cancer.
The median age of diagnosis in the newer generation was 42, but 47 in the older women. The study authors report that this is worrisome because it could mean that the cancer is developing earlier.
"These findings are certainly concerning and could have implications on the screening and genetic counseling of these women," said study co-author Dr. Jennifer Litton, an assistant professor at M.D. Anderson Cancer Center, in a news release from the center. "In BRCA-positive women with breast cancer, we actually might be seeing true anticipation -- the phenotype or cancer coming out earlier per generation. This suggests more than the mutation could be involved, perhaps lifestyle and environmental factors are also coming into play."
Learn more about the BRCA genetic mutation from the U.S. National Cancer Institute.