Patients with breast cancer can sometimes experience a change in biomarkers due to the irregular nature of the disease. And a recent review of patients with breast cancer show that about 40% of women had a change in at least one of these biomarkers between preliminary and principal treatment, an occurrence that might indicate a better chance of recurrence-free survival.
The 398-patient study conducted by researchers from the University of Texas MD Anderson Cancer Center noted changes in receptor status after neoadjuvant chemotherapy and whether this shift had an effect on the outcomes. They followed the patients for a median of 40 months after neoadjuvant chemotherapy that included either an anthracycline-, taxane- or anthracycline/taxane-based regimen, according to a report from CancerNetwork.
During those 40 months, 32% of the patients died, 41.8% recurred and 40.7% had a change in at least one biomarker status, the most substantial numbers of whom shifted from HER2-positive to HER2-negative or PR-positive to PR-negative. And in a 35-person subgroup treated with the HER2/neu receptor antibody trastuzumab, 45.7% had a biomarker change from HER2 positive to HER2 negative. The researchers presented these data at the American Society of Clinical Oncology Breast Cancer Symposium 2013.
Importantly, the researchers found that a change in biomarker status significantly improved recurrence-free survival rates compared to those without a change. In the study, 63% of women with a status change showed a 5-year recurrence-free survival, as opposed to 48% of patients without a change.
"It is still uncertain if mechanisms for tumor discordance such as tumor heterogeneity, clonal selection, genetic switch and differential treatment response would be main explanations for the lack of stability in tumor biomarkers," Dr. Napa Parinyanitikul of the University of Texas MD Anderson Cancer Center said, as reported by CancerNetwork. "Further large prospective studies may help to confirm our findings and to determine the impact of biomarker changes in long-term survival outcomes."
- here's the CancerNetwork report