BRCA status impacts early breast cancer outcome
NEW YORK (Reuters Health) - The outcome of women with breast cancer and a BRCA1 gene mutation is likely to be "unsatisfactory," even when tumors are caught at an apparently early stage through a surveillance program, research indicates.
On the other hand, women with surveillance-detected breast cancer and a BRCA2 gene mutation, or no detectable mutation, are apt to have a good outcome, the study shows.
These findings demonstrate clear differences in outcome of genetically different breast cancers detected through a surveillance program, Dr. Pat Moller from Rikshospitalet-Radiumhospitalet Clinic Center, Oslo, Norway and colleagues write in the latest issue of the International Journal of Cancer.
In addition to family history of breast cancer, having a BRCA1 or BRCA2 gene mutation raises a woman's risk of developing breast cancer. Moller's team analyzed the outcome by mutation status of 442 women with familial breast cancer enrolled in a program for early diagnosis and treatment.
Eighty-nine of the women (20 percent) had BRCA1 mutations, 35 (8 percent) had BRCA2 mutations and 318 (72 percent) had no detectable mutation.
According to the team, the 5-year survival rate was much lower in BRCA1 carriers (73 percent) compared with BRCA2 carriers (96 percent) and the non-mutation carriers (92 percent).
"The present findings should be taken into account when women with significant family histories of breast cancer make informed choices about their management," the researchers conclude.
SOURCE: International Journal of Cancer, September 1, 2007.
What breastcancer.org says about this article…
BRCA status impacts early breast cancer outcome
Most inherited cases of breast cancer have been associated with two genes: BRCA1, which stands for BReast CAncer gene 1, and BRCA2, or BReast CAncer gene 2. Women with an abnormal BRCA1 or BRCA2 gene have up to an 85% risk of developing breast cancer by age 70. Abnormal BRCA1 and BRCA2 genes are found in 5% to 10% of all breast cancer cases in the United States.
The study reviewed here found that women with an abnormal BRCA1 gene had a worse prognosis than women with an abnormal BRCA2 gene 5 years after diagnosis. Women with an abnormal BRCA2 gene had a prognosis that was basically the same as women with no abnormal breast cancer genes 5 years after diagnosis. Five years after diagnosis:
- 73% of women with an abnormal BRCA1 gene were alive
- 96% of women with an abnormal BRCA2 gene were alive
- 92% of women with no abnormal breast cancer genes were alive
The researchers suggest that this difference in prognosis should be considered when deciding on treatment for women with an abnormal BRCA1 gene.
Another study found that women with an abnormal BRCA1 or BRCA2 gene have the same prognosis as women who don't have abnormal breast cancer genes 10 years after diagnosis (5 more years after diagnosis than the study reviewed here). There are several possible reasons why these two studies seem to have different results:
- It might be that women with an abnormal BRCA1 gene have a worse prognosis in the first 5 years after diagnosis, but do better in the next 5 years so their overall prognosis at 10 years is the same as women with an abnormal BRCA2 gene or no abnormal genes.
- The study reviewed here is small. There were only 89 women with an abnormal BRCA1 gene and only 35 women with an abnormal BRCA2 gene. The results of this study may have been different if more women with abnormal breast cancer genes were followed.
- There may have been other differences between the women that influenced the results.
If you have an abnormal BRCA1 or BRCA2 gene, your risk of developing breast cancer is higher than the average woman's. You can't change your genetics. But you can make sure that if breast cancer develops it is diagnosed as early as possible. You and your doctor should develop a special screening plan that includes more frequent screenings starting at an early age, and possibly MRI scans or other screening techniques. Abnormal breast cancer genes also increase the risk of ovarian cancer, so it's important to discuss this with your doctor, too. To learn more, visit the breastcancer.org Genetics and Breast Cancer Risk section.
