Swollen lymph nodes are among the common causes of a lump behind the ear. Known specifically as cervical lymphadenopathy, the condition is caused when lymph nodes behind the ear—called cervical ...

a swelling of the lymph nodes in the armpits (axillary nodes), groin (inguinal nodes), neck (cervical nodes), chest (mediastinal nodes), and abdomen (abdominal nodes). While the swelling may ...