February 2025 Newsletter

How common are BRCA1 and BRCA2 mutations

IMPORTANT FACT 2: Inherited mutations in BRCA1 and BRCA2 are not common. About 1 in 500 to 1 in 800 individuals in the general population have a mutation.

However, individuals of Ashkenazi Jewish descent have a 1 in 40 chance of carrying a BRCA1/2 mutation. This is an at least ten times greater probability than that of the general population.

Women: How much does an inherited harmful variant in BRCA1 or BRCA2 increase a woman’s risk of breast cancer

General population risk of breast cancer in women: ~13% (13 out of 100) of women in the general population will develop breast cancer sometime during their lives.

In women who have a harmful BRCA variant the risk is higher:

Harmful BRCA1 variant: 55%–72% (55-72 out of 100) women who inherit the harmful variant of BRCA 1 will develop breast cancer by 70–80 years of age.

Harmful BRCA2 variant: 45%–69% (45 -69 out of 100) women who inherit the harmful variant of BRCA 2 will develop breast cancer by 70–80 years of age.

IMPORTANT FACT 3: In essence, having the harmful variant of either BRCA 1 or 2 increases a woman’s chances of developing cancer.

Women with harmful BRCA 1 or 2 variations are also at increased risk of ovarian, and other types of cancer. People who have inherited a harmful variant in BRCA1 and BRCA2 also tend to develop cancer at younger ages than people who do not have such a variant.

It’s important to remember, a harmful variant in BRCA1 or BRCA2 can be inherited from either parent.

Men: How much does an inherited harmful variant in BRCA1 or BRCA2 increase a man’s risk of cancer

While breast cancer is rare in men, it can happen. The average male has a 0.1% (1 in a 1000) lifetime risk of developing breast cancer, but in men with BRCA mutations, the risk is higher: 1 to 5% (1-5/100) lifetime risk for men with BRCA1 mutations and 5 to 10% (5-10/100) lifetime risk for men with BRCA2 mutations.

IMPORTANT FACT 4: Men with BRCA2 variants, and to a lesser extent BRCA1 variants, are also at increased risk of breast cancer and prostate cancer.

Who should consider genetic counseling and testing for BRCA1 and BRCA2 variants

Anyone who is concerned about the possibility that they may have a harmful variant in the BRCA1 or BRCA2 gene should discuss their concerns with their health care provider or a genetic counselor, especially if you have a strong family history of BRCA related cancers.

• Men in a family with a known BRCA mutation
• Men with a personal history of male breast cancer
• Men with a personal history of prostate or pancreatic cancer with at least one close relative (male or female) with the following:
  • Breast cancer under age 50
  • Ovarian, pancreatic or prostate cancer at any age
• Men with a personal history of pancreatic cancer and are of Ashkenazi Jewish ancestry
• Men with a family history of breast cancer under age 50 or cancer in both breasts or ovarian cancer or any of the above criteria may also be recommended for genetic counseling

IMPORTANT FACT 5: Your family medical history is important. This includes your first degree (parents, siblings, children), second degree (half-siblings, grandparents, aunts, uncles) and third degree (cousins, great grandparents, great-aunts, great-uncles) relatives.

Medical management of men with a BRCA 1/2 mutation

Age 35 onward: male BRCA mutation carriers should begin yearly clinical breast exams with a physician.

Age 40 onward: prostate cancer screenings are recommended for BRCA2 carriers and considered for BRCA1 carriers.

Men with a BRCA mutation and a family history of pancreatic cancer or melanoma should speak to a physician to develop a personalized screening plan for those cancers.

IMPORTANT FACT 6: Speak to your healthcare providers about a personalized screening plan for these cancers

IMPORTANT FACT 7: Take a deep breath and remember the flip side of the coin, you know, that half glass full vs half glass empty thing that is life in general:

• 1 in 500 - 800 individuals in the general population have a BRCA 1/2 mutation. This means 499-799 of those 500-800 individuals DO NOT have the BRCA 1/2 mutation.
• Even if you are a man with a known BRCA mutation, your lifetime risk of developing breast cancer, though higher, is 1-5/100 for men with BRCA1 mutations and 5-10/100 for men with BRCA2 mutations. This means your possibility of NOT developing breast cancer is >90/100.
• As with breast cancer in women, early detection and management has a significantly positive effect on survival and outcomes. At any age, men should seek medical advice if they develop:
  • Enlarged breast
  • Pain or a lump around the nipple
  • Reddening of the skin on the breast
  • Inversion of the nipple
  • A nipple discharge
  • Skin dimpling around the nipple.

Where can I get more information about BRCA1/2 and help finding a genetics specialist

Visit basser.org or call the Basser Center for BRCA at 215.662.2748. The National Society of Genetic Counselors (nsgc.org) is also a helpful resource for finding genetics professionals in your area.

Thank you for reading, and stay healthy, continue screening for you and your loved ones!!

And to our Maina Foundation newsletter readers, thank you for reading and your valuable support! Please consider forwarding this newsletter to anyone who may benefit from this information.