Germ cell tumors are more common in young men, they are very rare in women, they are often malignant and symptomatic, and like other mediastinal tumors they are usually detected by chest x-ray which where there is a widening of the mediastinum.
Otra teoría se refiere a que se trata de células metastásicas de tumores originados en las gónadas, sin embargo, es raro encontrar la asociación de tumores germinales del mediastino y en las gónadas.