According to a recent article published in The Lancet, young women with BRCA1 or BRCA2 mutations who have been diagnosed with breast cancer have an increased risk of developing a second breast cancer following conservative therapy.
Patients with a mutation within genes referred to as BRCA1 or BRCA2 are at an increased risk of developing breast cancer in both breasts and at an earlier age than the general population. In addition, clinical data has indicated that young women diagnosed with breast cancer tend to have worse long-term outcomes than older women. Due to the fact that patients carrying one or both of these mutations are at an increased risk for breast cancer, researchers are evaluating screening and prevention measures for these women, in order to diagnose and treat the cancer in its earliest stages when it is most curable, or prevent its occurrence altogether. Some women with BRCA1 or BRCA2 mutations undergo a bilateral mastectomy prior to the diagnosis of any cancer, or following the diagnosis of cancer in one breast. However, in the past, the standard treatment of early-stage breast cancer involving BRCA1 or BRCA2 mutations was the surgical removal of the cancer (lumpectomy) followed by radiation.
Researchers from Yale University recently evaluated data of treatment and outcomes of 127 women with early-stage breast cancer who were treated at their institution. Of these patients, 15 had mutations within their BRCA1 gene and seven had mutations within their BRCA2 gene. Patients were 42 years of age or younger and all had undergone a lumpectomy plus local radiation. No patient was receiving any preventive measures, such as chemotherapy or anti-estrogen therapy, and no patient had undergone the removal of their ovaries.
Twelve years following the initial diagnosis of breast cancer, 49% of patients with BRCA1 or BRCA2 mutations had a second cancer in the same breast as the initial cancer (ipsilateral), compared to only 21% of women without these gene mutations. A second breast cancer occurred in the other breast (contralateral) in 42% of patients with BRCA1 or BRCA2 mutations, compared to only 9% of women without these mutations. The average time to develop a second cancer was six to eight years following initial diagnosis.
These results indicate that young women with BRCA1 or BRCA2 mutations who have been diagnosed with early-stage breast cancer and treated with a lumpectomy and radiation are at an increased risk for the development of a second cancer in either breast. The researchers conducting this trial concluded that careful and frequent monitoring of both breasts is recommended for young breast cancer patients with BRCA1 or BRCA2 mutations in order to detect and treat cancer early. The researchers also suggest that treatment, such as chemotherapy or anti-estrogen therapy for hormone-positive cancers following a lumpectomy plus radiation may be considered, in order to further reduce the risk of a second cancer. Furthermore, women with BRCA1 or BRCA2 mutations who have severe anxiety about developing a second cancer may wish to consider more extreme preventive measures, such as a bilateral mastectomy. It is important that patients with BRCA1 or BRCA2 mutations discuss the risks and benefits of all options with their physician and a genetic counselor.
Reference: Haffty B, Harrold E, Khan A, et al. Outcome of conservatively managed early-onset breast cancer by BRCA1/2 status.
The Lancet. 2002;359:1471-1477.