Lymph nodes are small glands that filter lymph, the clear fluid that circulates through the lymphatic system. During an infection, they accumulate bacteria or dead or diseased cells and may swell.
All that commotion in response to a threat is what shows up as swelling. That can look different depending on the person, but generally, a lymph node bigger than one centimetre across is considered ...
Usually, swollen chest lymph nodes are too deep in the chest for a person to feel them. Any swollen lymph nodes in the chest appear on imaging scans. Swelling can indicate an underlying condition.