A new study has found that obesity may contribute to the progression of early-stage breast lesions into invasive breast cancer through a distinct biological process, offering fresh insights into how excess body weight influences cancer development.
Researchers from the University of Oklahoma Health Sciences Center found that tumours in obese patients followed a different pathway from those in non-obese patients. Instead of showing the usual mechanisms linked to cancer spread, the tumours displayed a stress-adaptive phenotype, driven by metabolic stress, inflammation and changes in the tumour’s surrounding environment.
The study focused on ductal carcinoma in situ (DCIS), also known as stage 0 breast cancer, which accounts for nearly 25% of newly detected breast lesions. While DCIS increases the lifetime risk of invasive breast cancer, not all cases progress to invasive ductal carcinoma (IDC).
Researchers found that the transition from DCIS to invasive cancer is influenced not only by tumour cells but also by interactions between epithelial, immune and stromal cells. Obesity appears to affect all of these components, altering how they communicate and potentially increasing the risk of cancer invasion.
The study also identified increased activity of an enzyme called SULF2, which is associated with cancer progression and may serve as a future therapeutic target.
Lead researchers said the findings suggest that current methods used to predict which early breast cancers will become invasive may not be sufficient for obese patients. They believe future diagnostic models should also consider metabolic health, immune responses and obesity-related molecular changes to better assess individual risk and guide treatment decisions.
The findings could help improve personalised care and reduce both overtreatment and undertreatment of patients diagnosed with early-stage breast cancer.
