Hereditary Breast and Ovarian Cancer (HBOC) is most often caused by mutations in BRCA1 or BRCA2. BRCA1 & BRCA2 mutations are associated with high risks for female breast cancer, ovarian cancer, male breast cancer, prostate cancer, pancreatic cancer, and melanoma.
In honor of Breast Cancer Awareness Month, I’d like to discuss 5 common misconceptions I often hear from people when discussing HBOC.
Misconception #1: You can’t inherit a risk factor for breast or ovarian cancer from your father.
You actually can inherit a risk factor for breast or ovarian cancer from your father. You inherit half of your genes from your mother and half of your genes from your father. Most genes linked to hereditary breast and ovarian cancer are not tied to sex chromosomes, and are present in both men and women equally. This is why both sides of the family are of equal importance when we ask family history questions.
Misconception #2: Women are the only people who can get breast cancer.
According to the American Cancer Society, 1 in 1,000 (0.1%) men will develop breast cancer. The general population risk for men to develop breast cancer may be fairly low, but individuals who do develop male breast cancer should consider genetic counseling and genetic testing for HBOC. Men who have a BRCA1 mutation have a 1-2% risk to develop breast cancer and men who have a BRCA2 mutation have about a 5-10% risk to develop male breast cancer.
Misconception #3: If I test positive for a gene mutation related to hereditary breast cancer, I will develop breast cancer.
Most risks tied to hereditary breast cancer gene mutations are not 100%. For example, a woman with a BRCA1 mutation has between a 46-87% lifetime risk to develop breast cancer. The general population risk for breast cancer is 12-13%. The risks for a woman with a BRCA1 mutation to develop breast cancer are high, but they are not 100%, which means there are women who carry these types of mutations who do not automatically develop breast cancer.
Misconception #4: I look just like my mother. She has a BRCA1 mutation, so that means I’m BRCA1 mutation positive too.
Although you may look more like your mother, it does not mean you carry the same risk factors that she does. Your mother passes on half of her genes to you, and it is a “flip of a coin” or 50/50 as to which set of genes you inherit.
Misconception #5: I’ve already had breast cancer, so genetic testing won’t be helpful to me or my family. It would be better for my unaffected daughter to get tested first.
In the world of Genetics, the information we can get from a genetic test can be more informative if we first test someone who has had the condition we are concerned about (i.e. breast cancer). If the unaffected daughter gets tested first, and her genetic testing is negative, it still does not tell us whether her mother who had breast cancer is carrying a hereditary risk factor for breast cancer. If we know that the mother is carrying a hereditary risk for breast cancer, genetic testing is more targeted and straight forward to interpret for her family members.
If you have questions regarding genetic testing for hereditary cancer syndromes or genetic counseling, please call the ProMedica Cancer Institute’s Cancer Genetics Program at 419-824-5073.
Sarah Adelsperger, MS, LCGC, is a board-certified genetic counselor specializing in cancer. Sarah joined Kelly Morse, MS, LCGC, in the Cancer Genetics Program in May 2015 at ProMedica Cancer Institute–the only program in Northwest Ohio and Southeast Michigan with two licensed and board-certified genetics counselors specializing in cancer genetics.