Pre-existing inflammation in the lungs may increase the risk that cancers beginning elsewhere will spread to that organ, according to new research from Weill Cornell Medicine.

Physicians have long noted an association between lung inflammation – seen in smokers or in people with lung diseases such as asthma, COPD and emphysema, and pneumonia – and the development of lung tumors. But it’s been unclear whether inflammation also increases the risk of pulmonary metastasis from other tumors.

In their study, published this week in the Proceedings of the National Academy of Sciences, the investigators reveal a mechanism by which this occurs, shedding light on how pre-existing lung inflammation creates an environment ripe for cancer spread to the organ. The findings may provide doctors new insights into how to treat and possibly prevent metastases.