 Metabolic syndrome MS is a cluster of disorders including hypertension, type II diabetes, dyslipidemia and obesity, and certain aspects of the MS are well described in relation to breast cancer. It has been shown that obesity is associated with an increased risk of developing breast cancer among postmenopausal women, obese patients present with more advanced cancers, and women who are overweight or obese at the time of breast cancer diagnosis or gain weight after diagnosis are at increased risk of cancer recurrence and death compared with leaner women. One study have shown that the effects of adjuvant therapy is less in obese breast cancer patients. An association between diabetes and breast cancer has also been observed. Other components of the MS, including low HDL-cholesterol, high triglycerides, hypertension, and serum testosterone are, however, less well described, but may be associated with an increased breast cancer risk and a worse breast cancer prognosis. A recent study showed that patients with MS present with more aggressive tumors. In patients with metastatic disease, response to chemotherapy appears to be inferior when the patient is diagnosed with MS, as well. Emerging evidence suggest that the MS may be quite prevalent among patients with breast cancer. 