HealthDay News — For women with breast cancer treated with primary systemic chemotherapy (PST), achieving axillary pathologic complete response (pCR) is associated with improved survival, according to a study published online December 30 in JAMA Oncology.
Sarah S. Mougalian, MD, from the University of Texas MD Anderson Cancer Center in Houston, and colleagues examined the long-term effect of axillary pCR on relapse-free survival (RFS) and overall survival (OS) among women who received a diagnosis of breast cancer stages II to III. Participants had cytologically confirmed axillary metastases and were treated with PST. Data were included for 1600 women, of whom 28.4% achieved axillary pCR.
The researchers found that patients who achieved axillary pCR were more likely to have human epidermal growth factor receptor 2 (HER2)-positive and triple-negative disease, pCR in the breast, and high-grade tumors (all P < 0.001), and to have lower clinical and pathological T stage (P = 0.002). For patients with axillary pCR and residual axillary disease, the 10-year OS rates were 84 and 57 percent, respectively, while the corresponding 10-year RFS rates were 79 and 50%. Axillary pCR was achieved by 67.1% of patients receiving HER2-targeted therapy for HER2-positive disease; the 10-year OS rates were 92 and 57% for those with axillary pCR and residual axillary disease, respectively; the corresponding 10-year RFS rates were 89 and 44%.
“Axillary pCR was associated with improved 10-year OS and RFS,” the authors write.