A novel study has found that obesity is associated with a distinct molecular program driving the transition from early-stage, premalignant breast lesions to invasive breast cancer. Rather than simply showing increased activation of classical invasive pathways, tumors from obese patients exhibited a distinct stress-adaptive phenotype. The findings from the study in The American Journal of Pathology, published by Elsevier, suggest that metabolic health could be an important factor in future risk stratification and treatment decision-making.