This mutation increases a woman’s breast-cancer risk nearly as much as BRCA. What to know

Have you heard of PALB2?

Everyone has two PALB2 genes, one from their mother and one from their father. When the genes work properly, they make a protein that works with another gene to repair damaged DNA and stop tumor growth.

But sometimes people inherit a mutated gene. When PALB2 is mutated, it can’t suppress tumor growth, increasing a person’s risk for getting cancer in certain parts, including breasts, ovaries, pancreas and prostate, said Sara Rhode, a genetic counselor at the Cleveland Clinic Maroone Cancer Center in Weston.

Research has shown that women with mutated PALB2 genes are at risk for breast cancer nearly as much as those who have the more well-known

BRCA genetic mutations, said Dr. Cassann Blake, a breast-oncology surgeon at Cleveland Clinic’s Weston location.

This makes PALB2 the “third most important breast cancer gene after BRCA1 and BRCA2,” according to the American College of Medical Genetics and Genomics.

Genetic testing is how mutated genes are identified, and while it can be helpful in determining a woman’s risk for breast cancer, not every woman needs to be tested, according to the American Cancer Society.

Doctors usually have patients undergo a health assessment, which looks at many factors, including the woman’s personal and family history of cancer, to determine if testing is needed.

However, clinical testing of PALB2 hasn’t been available for as long as genetic testing of BRCA1 and

BRCA2, so it’s likely that patients who were tested prior to 2013 didn’t have their PALB2 analyzed, according to Yale’s School of Medicine.

“So now, what we’re doing is, those patients that met criteria for genetic testing in the past, we’re bringing them back to retest with what we call expanded genetic testing,” said Dr. Alejandra Perez, a breast medical oncologist with Sylvester Comprehensive Cancer Center at the University of Miami.

The PALB2 mutation is associated with an increased risk of breast cancer. Men can get breast cancer too, but it’s rare. A PALB2 mutation can also increase the risk for ovarian and pancreatic cancer.

For women in the general population, the risk of developing breast cancer is 12.9% or 1 in 8, according to the National Cancer Institute.

For women with a mutated PALB2, the risk of developing breast cancer by age 70 is higher, about 40%-60%, said Blake, the Cleveland Clinic doctor.

Women with BRCA mutations can have up to an 80% chance of developing breast cancer, said Perez, the Sylvester doctor who is the medical director of the Braman Family Breast Cancer Institute in Plantation.

Women with a family history of breast cancer are at higher risk of developing breast cancer. However, it’s worth noting that most women with a family history of breast cancer “do not have an inherited gene change that greatly affects their risk,” according to the American Cancer Society. Likewise, a woman can have a mutated gene even if she doesn’t have a family history of cancer, Perez said.

People with PALB2 are slightly more prone to develop an “estrogen receptor negative breast cancer, which increases the likelihood that their cancer may need to be treated with chemotherapy,” Blake said.

Perez said PALB2 patients also share some characteristics: The women developing cancer are usually younger (they’re pre-menopausal), they might have lymph-node involvement, and their diagnosis is usually triplenegative breast cancer or bilateral breast cancer. The tumors are usually bigger, too, due to the late diagnosis.

And while standard treatments do exist, such as mastectomy and chemotherapy, some patients will undergo new treatments that are being tested in clinical trials.

In terms of testing, women with the mutation should alternate every six months between breast MRIs and mammograms, according to Perez and Blake. This way, if cancer does start to develop, it can be detected early.

Women with the PALB2 mutation who have a family history of breast cancer can also undergo a preventative double mastectomy to lower their risk, the doctors said.

Women should consider lifestyle changes, too, to reduce their risk of breast cancer., including not smoking, not drinking too much alcohol. They should also eat healthy and exercise to avoid being overweight. Obesity can increase a woman’s risk for breast cancer.