Gene inheritance patterns influence age of diagnosis in BRCA families

December 09, 2011

LAKE SUCCESS, NY -- Women who inherit the cancer genes BRCA1 or BRCA2 from their paternal lineage may get a diagnosis a decade earlier than those women who carry the cancer genes from their mother and her ancestors, according to a new study by researchers at the North Shore-LIJ Health System's Monter Cancer Center in Lake Success, NY. The findings were reported on Thursday, Dec. 8, at the San Antonio Breast Cancer Symposium.

Iuliana Shapira, MD, North director of cancer genetics, and her colleagues conducted a retrospective review of 130 breast or ovarian cancer patients with the BRCA1 or BRCA2 mutations. They chose only those patients who knew the parent of origin. In other words, they could follow along their family tree to see where the breast cancer gene originated from. Some of their families had their own genetic tests done. For others, it was a matter of following the family pedigree.

As expected, a person had a 50-50 chance of getting a mutant BRCA gene from their mother or their father's branch that carried the mutation. It is an autosomal dominant mutation. Looking at the family maps revealed some surprising findings. Contrary to the notion that the BRCA mutations are associated more commonly with Ashkenazi Jews, the scientists found that the BRCA mutations were also in families of Irish and Jamaican descent. "No one had ever conducted a study to look at the parent-of-origin effects," said Dr. Shapira. "Genetic diseases may display parent-of-origin effects. In such cases, the risk depends on the specific parent or origin allele. Cancer penetrance in mutations carriers may be determined by the parent origin of BRCA mutation."

They analyzed 1,889 consecutive (136 ovarian + 1753 breast) breast (BrCa) or ovarian cancer (OvCa) patients presenting for treatment at the Monter Cancer Center between 2007 and 2010. In 130 patients with BRCA 1 or 2 mutations the parent of origin for the mutation was known. Of the 130 patients, two had both BRCA1 and BRCA2 mutated paternally inherited disease and were excluded from this analysis. Of the breast cancer patients: 28 patients had paternal and 29 had maternal BRCA1 mutations, 24 had paternal and 21 had maternal BRCA 2 mutations. Of the ovarian cancer patients, six had paternal and 10 had maternal BRCA1 mutations; seven had paternal and three had maternal BRCA2 mutations.

In carriers of BRCA mutations, the mean age at diagnosis for ovarian cancer was 51 (range 21-70) and for breast cancer was 43 (range 24-78). But when they compared the mean age at diagnosis in the maternal versus paternal inheritance, they were surprised to find that breast cancer patients with a BRCA1 maternal inheritance, the age of diagnosis was on average around 45. By comparison, women with BRCA1 paternal inheritance were diagnosed around 38. For breast cancer BRCA2 maternal inheritance, the average age of diagnosis was 50 compared to 41 years old for those with a BRCA2 paternal inheritance.

There was no significant difference between paternal and maternal age of ovarian cancer diagnosis of BRCA1 or BRCA2 mutations.

"If this observation is duplicated in larger cohorts the results will have important implications for recommendation of surgical risk reduction in BRCA mutation carriers," said Dr. Shapira. "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."
-end-


Northwell Health

Related Breast Cancer Articles from Brightsurf:

Oncotarget: IGF2 expression in breast cancer tumors and in breast cancer cells
The Oncotarget authors propose that methylation of DVDMR represents a novel epigenetic biomarker that determines the levels of IGF2 protein expression in breast cancer.

Breast cancer: AI predicts which pre-malignant breast lesions will progress to advanced cancer
New research at Case Western Reserve University in Cleveland, Ohio, could help better determine which patients diagnosed with the pre-malignant breast cancer commonly as stage 0 are likely to progress to invasive breast cancer and therefore might benefit from additional therapy over and above surgery alone.

Partial breast irradiation effective treatment option for low-risk breast cancer
Partial breast irradiation produces similar long-term survival rates and risk for recurrence compared with whole breast irradiation for many women with low-risk, early stage breast cancer, according to new clinical data from a national clinical trial involving researchers from The Ohio State University Comprehensive Cancer Center - Arthur G.

Breast screening linked to 60 per cent lower risk of breast cancer death in first 10 years
Women who take part in breast screening have a significantly greater benefit from treatments than those who are not screened, according to a study of more than 50,000 women.

More clues revealed in link between normal breast changes and invasive breast cancer
A research team, led by investigators from Georgetown Lombardi Comprehensive Cancer Center, details how a natural and dramatic process -- changes in mammary glands to accommodate breastfeeding -- uses a molecular process believed to contribute to survival of pre-malignant breast cells.

Breast tissue tumor suppressor PTEN: A potential Achilles heel for breast cancer cells
A highly collaborative team of researchers at the Medical University of South Carolina and Ohio State University report in Nature Communications that they have identified a novel pathway for connective tissue PTEN in breast cancer cell response to radiotherapy.

Computers equal radiologists in assessing breast density and associated breast cancer risk
Automated breast-density evaluation was just as accurate in predicting women's risk of breast cancer, found and not found by mammography, as subjective evaluation done by radiologists, in a study led by researchers at UC San Francisco and Mayo Clinic.

Blood test can effectively rule out breast cancer, regardless of breast density
A new study published in PLOS ONE demonstrates that Videssa® Breast, a multi-protein biomarker blood test for breast cancer, is unaffected by breast density and can reliably rule out breast cancer in women with both dense and non-dense breast tissue.

Study shows influence of surgeons on likelihood of removal of healthy breast after breast cancer dia
Attending surgeons can have a strong influence on whether a patient undergoes contralateral prophylactic mastectomy after a diagnosis of breast cancer, according to a study published by JAMA Surgery.

Young breast cancer patients undergoing breast conserving surgery see improved prognosis
A new analysis indicates that breast cancer prognoses have improved over time in young women treated with breast conserving surgery.

Read More: Breast Cancer News and Breast Cancer Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.