Do Obese Patients Present With More Advanced Breast Cancer?

Obesity is a known risk factor for breast cancer development; however, it is unclear whether obesity is associated with more aggressive disease. We sought to determine the relationship between obesity and tumor characteristics in breast cancer patients.

Medical records of invasive breast cancer patients undergoing mastectomy at our institution between January 2010 and April 2018 were reviewed. Patients who had received neoadjuvant therapy were excluded. Patients were separated into obese (body mass index [BMI] ≥ 30 kg/m²) and nonobese (BMI < 30 kg/m²) categories and compared using nonparametric statistical analyses.

Of the 415 patients in this cohort, 124 (29.9%) were obese. Obese patients were more likely to present with larger tumors (tumor size ≥ 2 cm: 53.2% vs 41.0%, P = .024) and more node-positive disease (46.8% vs 28.9%, P = .001). Controlling for confounders, obesity was independently associated with node-positive disease (odds ratio [OR] = 2.00; 95% CI 1.24-3.21, P = .004), but not with tumor size ≥ 2 cm (OR = 1.38; 95% CI 0.87-2.21, P = .174).

Obesity is associated with node-positive disease at presentation independent of other factors.