The MINDACT trial sought to create a systematic comparison of therapeutic outcomes for different populations stratified according to clinical and genomic risk categories. Of the 6693 patients involved, all were categorized as a combination of clinical-high, clinical-low, genomic-high and genomic-low risk. The intended outcome of the trial was to determine if clinical-low, genomic-high patients, and clinical-high, genomic-low patients, had positive outcomes without receiving adjuvant therapy. Overall, the percentage of patients with 5-year distant metastasis-free survival was very high, at 91%.
This study presents a long-term follow-up analysis of patients that were classed as clinical-low, with stratification between genomic-high and genomic-low patients. Specifically, distant metastasis-free survival is compared between C-low patients who are G-high and G-low, depending on whether or not they received adjuvant therapy. Survival estimates are calculated using Kaplan-Meier estimates, and hazard ratios with 95% confidence intervals from Cox-regression models are used, adjusted for stratification.
It was found that all C-low, G-low patients have excellent 5 and 8 year survival rates. Of the patients that are C-low, G-high, and were given adjuvant chemotherapy, a 1.5% higher distant metastasis-free survival can be seen in the data. The potential benefit of adjuvant chemotherapy on this group is especially notable in those under 50 years of age. The study concludes that stratifying the MINDACT trial data in the way indicated does make clear some disparities, especially age-related. The potential benefit of adjuvant chemotherapy on C-low, G-high patients remains to be more firmly established. However, according to the analysis provided here, it seems especially relevant to younger patients.