ASCO20: MINDACT Update Supports Longer-Term Use of MammaPrint in Clinical Decision-Making
Posted: Tuesday, June 9, 2020
An updated analysis of the phase III MINDACT study showed that patients with low genomic–risk breast cancer who underwent MammaPrint genetic testing, and were subsequently not given chemotherapy, maintained high rates of distant metastasis–free survival in the longer term, past the primary endpoint of 5 years. Fatima Cardoso, MD, of the Champalimaud Cancer Center in Lisbon, and colleagues presented these MINDACT study updates during the ASCO20 Virtual Scientific Program (Abstract 506).
In this analysis, the researchers assessed whether the primary distant metastasis–free survival endpoints of 644 patients with high clinical and low genomic risk who received no chemotherapy continued to be met over 8 years of follow-up. They also compared the overall and distant metastasis–free survival rates between 749 and 748 patients with high clinical and low genomic risk who did or did not receive chemotherapy, respectively.
After a median follow-up of 8.7 years, the 5-year and 8-year distant metastasis–free survival rates of patients who did not receive chemotherapy were 94.8% and 89.4%, respectively. For patients who did receive chemotherapy, distant metastasis–free survival rates were 95.7% and 92.0%, respectively. Overall survival rates were 94.3% and 95.7%, in the no-chemotherapy and chemotherapy groups, respectively.
Although increased instances of distant relapse did occur in patients who did not receive chemotherapy, the authors concluded this difference was “small in light of [chemotherapy’s] harmful effects. The level 1A evidence for the clinical utility of the 70-gene signature for adjuvant [chemotherapy] decision-making is maintained.”
Disclosure: For full disclosures of the study authors, visit coi.asco.org.
