Family Tree May Affect Diagnosis Age in Some Breast Cancers
THURSDAY, Dec. 8 -- Some women who inherit the BRCA1 or BRCA2 breast and ovarian cancer genes from their father may be diagnosed with breast cancer nearly a decade earlier than those who inherit the genes from their mother, a new study indicates.
Researchers examined the family trees of 128 breast or ovarian cancer patients with the BRCA1 or BRCA2 mutations to determine the origins of the patients' cancer genes.
"No one had ever conducted a study to look at the parent-of-origin effects," lead researcher Dr. Iuliana Shapira said in a news release from the Monter Cancer Center in Lake Success, N.Y.
Of the breast cancer patients, 28 had paternal (from the father) and 29 had maternal (from the mother) BRCA1 mutations, while 24 had paternal and 21 had maternal BRCA2 mutations.
Of the ovarian cancer patients, six had paternal and 10 had maternal BRCA1 mutations, while seven had paternal and three had maternal BRCA2 mutations, according to the researchers.
The mean age at diagnosis was 51 (ranging from 21 to 70) for ovarian cancer and 43 (ranging from 24 to 78) for breast cancer. However, the average age of diagnosis for breast cancer patients with a maternal BRCA1 mutation was 45, compared with about 38 for those with a paternal BRCA1 mutation.
Women with a maternal BRCA2 mutation were diagnosed with breast cancer at an average age of 50, compared to 41 for those with a paternal BRCA2 mutation.
There were no significant differences in the ages that women with paternal or maternal BRCA1 or BRCA2 mutations were diagnosed with ovarian cancer.
"If this observation is duplicated in larger cohorts, the results will have important implications for recommendation of surgical risk reduction in BRCA mutation carriers," Shapira, director of cancer genetics at Monter, said in a center news release.
"That would mean that doctors might think about watching and waiting in young woman with BRCA mutations inherited from her mother's family and being more aggressive in young women who inherited the mutation from their father's side," she explained.
The study was to be presented Thursday at the San Antonio Breast Cancer Symposium. The data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
The U.S. National Cancer Institute has more about BRCA1 and BRCA2.
Posted: December 2011