Which is the largest lymph node region in the human body?

The neck is one of the largest and most important lymph node regions in the human body, with many nodes clustered along the cervical chains. These lymph nodes filter lymph fluid and trap pathogens or abnormal cells. They are often among the first to swell during infections of the throat, ears, or upper respiratory tract. Similar clusters also exist in the armpits and groin. Because the neck is close to the head and upper airways, it is an especially active immune checkpoint.