According to the results of a study published in the Journal of Clinical Oncology, women with early-stage breast cancer that is estrogen receptor-negative, progesterone receptor-negative, and HER2-negative (triple negative breast cancer) are more likely than other women to develop distant metastases. Women with triple negative breast cancer did not, however, have an increased risk of local recurrence.
Breast cancer is the most commonly diagnosed cancer in women in the United States. Although cure rates have improved dramatically over the past few decades, a significant portion of women with breast cancer still experience a recurrence and die from their disease. Researchers have therefore focused on identifying characteristics of breast tumors that influence prognosis or response to particular therapies.
“Triple negative” breast cancer refers to breast cancer that is estrogen receptor-negative, progesterone receptor-negative, and HER2-negative. These tumors appear to have a relatively poor prognosis. They are more common in African American women and in women with a BRCA1 gene mutation.
To describe patient outcomes among women with and without triple negative breast cancer, researchers conducted a study among 482 women with early-stage breast cancer. Of the 482 women in the study, 177 had triple negative breast cancer. All women were treated with lumpectomy and radiation therapy. Some women also received chemotherapy.
- After five years 67% of the women with triple negative breast cancer were free of distant metastases, compared to 82% of the other women.
- After accounting for several other factors that may influence the risk of distant metastases, women with triple negative breast cancer were roughly twice as likely as other women to develop distant metastases.
- Risk of local recurrence (recurrence in the treated breast) did not differ between women with and without triple negative.
- Eight out of ten women with a BRCA1 gene mutation were triple negative. One out of seven women with a BRCA2 gene mutation was triple negative.
The researchers conclude that among women with early-stage breast cancer treated with lumpectomy and radiation therapy (with or without chemotherapy), those with triple negative breast cancer have a worse prognosis. Additional research is needed to identify the optimal treatment strategy for these women.
The researchers note, however, that the women with triple negative breast cancer did not have an increased risk of local cancer recurrence, suggesting that these women are suitable candidates for breast conserving surgery.
Reference: Haffty BG, Yang Q, Reiss M et al. Locoregional Relapse and Distant Metastasis in Conservatively Managed Triple Negative Early-stage Breast Cancer. Journal of Clinical Oncology. Early online publication November 20, 2006.