Most, but not all, triple-negative breast cancers are basal-like.
Triple-negative breast tumors have been correlated with onset at a younger age, higher mean tumor size, higher-grade tumors, and, in some cases, a higher rate of node positivity.
Basal-like breast tumors were more likely among women who were younger at the onset of menstruation; have borne several children; were at a younger age at full-term pregnancy; had a shorter duration of breast-feeding; and higher body mass index (BMI) and waist-to-hip ratio (WHR), especially among premenopausal patients.
Women with triple-negative breast cancer were much more likely to develop a recurrence during the first 3 years following therapy with rapid declines thereafter. Translation: We can relax a bit after three years.
Patients with a “pathologic complete response”—meaning all traces of the cancer were eliminated— had excellent outcomes regardless of whether they were hormone positive or negative.
Source: C. Anders and L. A. Carey, “Understanding and Treating Triple-Negative Breast Cancer,” Oncology, Vol. 22, No. 11, October 1, 2008.