A germ cell tumor is a type of cancer that originates from germ cells, which are the cells responsible for producing sperm and eggs. These tumors can develop in various parts of the body, including the testes, ovaries, and mediastinum. Germ cell tumors can be classified into two main categories: seminomas and non-seminomas, each with different characteristics and treatment approaches. These tumors can occur in both children and adults, and their symptoms may vary depending on the tumor's location. Common signs include swelling or a mass in the affected area, pain, or hormonal changes. Early diagnosis and treatment are crucial for improving outcomes, often involving surgery, chemotherapy, or radiation therapy.