BRCA Genetic Mutations and Cancer – Personalized Medicine in Action
BRCA Gene Mutations in Women
According to the US National Cancer Institute, women with a faulty BRCA mutation are about 5 times more likely to develop breast cancer and 15-40% will develop ovarian cancer, compared to 1.4% of the general population.
In May, actress Angela Jolie wrote an op-ed for the New York Times entitled “My Medical Choice.” In her article, Jolie revealed that she had a double-mastectomy because she carries a faulty BRCA1 gene.
Jolie’s doctors estimated that she had an 87% chance of having breast cancer and a 50% chance of having ovarian cancer. “Once I knew that this was my reality, I decided to be proactive and to minimize the risk as much I could,” Jolie wrote. Jolie also has a family history of breast and ovarian cancer; her mother died from breast cancer at age 56.
The actress hopes that her action will spur other women to seek genetic testing if they have a strong family history of breast or ovarian cancer. “Cancer is still a word that strikes fear into people’s hearts, producing a deep sense of powerlessness. But today it is possible to find out through a blood test whether you are highly susceptible to breast and ovarian cancer, and then take action,” Jolie wrote.
BRCA Gene Mutations in Men
In London, a 53-year-old man made medical history by having his prostate preventatively removed because of his increased genetic risk for prostate cancer. The man carries a mutated BRCA2 gene, which a recent study linked to an increased risk of aggressive prostate cancer. He is the first person in the world to have a prophylactic radical prostatectomy.
The UK newspaper The Sunday Times published the story on May 19. The name of this businessman, who is married with children, has not been released. He has several family members who had breast or prostate cancer and did not want to risk having cancer in the future. The man learned he had a mutated BRCA2 gene because he participated in a genetic trial at the Institute of Cancer Research (ICR).
Initially, doctors did not want to perform a radical prostatectomy. His PSA blood test and MRI scan results were normal. However, a tissue sample taken from his prostate revealed microscopic malignant changes. The evidence of these changes combined with the BRCA2 mutation convinced doctors to move forward with the surgery.
His surgeon told The Sunday Times, “The relatively low level of cancerous cells we found in this man’s prostate before the operation would these days not normally prompt immediate surgery to remove the gland, but given what we now know about the nature of BRCA2, it was definitely the right thing to do for this patient.”
As more information on genetic susceptibility to cancer becomes available, medical care for patients with prostate cancer can be increasingly personalized.
BRCA Gene Mutations and Prostate Cancer Risk
Earlier studies at the ICR indicate that men with BRCA mutations are more likely to develop prostate cancer. A BRCA2 mutation especially increases the risk of prostate cancer. A BRCA2 mutation leads to a 8.6-fold increased risk of prostate cancer, while a BRCA1 mutation leads to a 3.4-fold increased risk.
Researchers published results of a new study in the Journal of Clinical Oncology involving more than 2,000 men and focusing on the effect of BRCA mutations on men with prostate cancer. The results suggested that men with BRCA2 mutations were more likely to have aggressive and lethal prostate cancer.
Among the men whose cancer had not spread out of the prostate at the time of diagnosis, more men with the genetic mutations had metastatic prostate cancer within 5 years when compared to men without mutations (23% vs. 7%). Men with BRCA2 mutations also had a lower survival rate. The study authors concluded that a BRCA2 test combined with other factors could be used as a prognostic test for prostate cancer risk for men with a family history that suggests possible BRCA mutations.
BRCA Gene Mutations and Prostate Cancer Treatment
When a patient is diagnosed with prostate cancer, it can be difficult to know how aggressive the cancer will be. Men with prostate cancer can choose to have treatment, such as a prostatectomy or radiation therapy, or they can choose active surveillance and wait to see how the disease progresses. Genetic research may help doctors and patients understand which approach is best for each person.