Ian Barron

MPharm PhD

Johns Hopkins

Research Fellow

PLCO (Learn more about this study)

PLCO-99

Sep 9, 2014

Pre-diagnostic obesity, smoking and lymph node involvement at breast cancer diagnosis.

Obesity and smoking prior to a breast cancer diagnosis have been associated with early disease recurrence and reduced breast-cancer specific survival in some studies. The mechanism by which these lifestyle factors may increase mortality in women with breast cancer is uncertain. Pre-clinical data suggests that activation of inflammation-related molecular pathways (cyclooxygenase/prostaglandin) in breast cancer can promote peritumoral lymphangiogenesis, lymphatic dysregulation and the development of lymph node and distant metastasis. Observational studies from our group [Cancer Research, In Press] and others [Rothwell et al. Lancet 2012] have also shown that pre-diagnostic use of aspirin, a cyclooxygenase inhibitor, may reduce the risk of developing metastasis.

Obesity and smoking have been associated with activation of these inflammation-related molecular pathways in breast cancer. They have also been associated with peritumoral lymphangiogenesis and functional impairment of the lymphatic vasculature. There is some evidence from prior clinical studies that obesity and smoking may be associated with an increased risk of presenting with lymphatic metastasis at the time of diagnosis. This may explain, in part, the increased breast cancer mortality in women with breast cancer. In this study we aim to examine associations between pre-diagnostic obesity, smoking and the presence of lymph node metastasis at breast cancer diagnosis among women in the US PLCO population.