Metabolic syndrome may affect survival outcomes in early breast cancer
Women with metabolic syndrome who are diagnosed with early breast cancer may have poorer survival outcomes, according to a study from Italy presented as a poster at SABCS 2018.
Researchers of this prospective, observational study identified 955 women diagnosed with early breast cancer between January 2009 and December 2013 at two hospitals in Naples, Italy (University Hospital Federico II and National Cancer Institute G. Pascale). Of the 494 women included in the analyses, 128 had metabolic syndrome (three to five of the following components: waist circumference >88 cm, blood pressure ≥130/≥85 mmHg, serum triglyceride ≥150 mg/dL, high-density lipoprotein (HDL) cholesterol <50 mg/dL, fasting glucose ≥110 mg/dL), while 366 did not have metabolic syndrome (zero, one, or two components of metabolic syndrome).
Women with metabolic syndrome tended to be older than their counterparts without metabolic syndrome (75.8 percent vs 41.0 percent older than 55 years; p<0.0001) and were more likely postmenopausal (87.5 percent vs 54.4 percent; p<0.0001).
After adjusting for age, menopausal status, cancer stage, immunohistochemistry subtypes, and adjuvant therapy, disease-free survival (DFS) was numerically greater among women without metabolic syndrome compared with women with metabolic syndrome (79.3 percent vs 68.8 percent; p=0.005), with a higher risk of DFS events among women with metabolic syndrome than those without (hazard ratio [HR], 1.64, 95 percent confidence interval [CI], 0.94–2.86; p=0.07). [SABCS 2018, abstract P2-08-15]
Overall survival (OS) rate was significantly greater among women without metabolic syndrome compared with women with metabolic syndrome (89.3 percent vs 71.2 percent; p<0.0001) with a higher event rate among women with metabolic syndrome than those without (HR, 3.83, 95 percent CI, 1.70–6.77; p=0.001).
Among the women categorized as not having metabolic syndrome, 122 and 244 had 0 and 1–2 components of metabolic syndrome, respectively. Women with no metabolic syndrome components had numerically but not significantly better DFS than those with 1–2 components (80.2 percent vs 78.9 percent; p=0.02, HR, 1.21, 95 percent CI, 0.68–2.17; p=0.5). However, OS was greater among those with 0 compared with 1–2 metabolic syndrome components (95.9 percent vs 86.0 percent; p<0.0001, HR, 4.39, 95 percent CI, 1.26–15.36; p=0.02).
Previous research has hinted that metabolic syndrome components may have an effect on breast cancer prognosis, said the researchers, though the link has not been sufficiently assessed in prospective studies.
“[This study demonstrated that] metabolic syndrome is correlated with poor outcomes in early breast cancer patients. [Furthermore], among patients without full criteria for metabolic syndrome diagnosis, the presence of one or two components of [metabolic] syndrome may predict for worse survival,” they said.
As such, they recommended that patients diagnosed with early breast cancer be examined for the presence of components of metabolic syndrome, and steps taken to reduce these risk factors including lifestyle modifications such as diet and exercise.