A Yolk Sac Tumor is a rare type of germ cell tumor that primarily affects children, particularly infants and young boys. It originates from the yolk sac, which is an early structure in embryonic development that provides nutrients to the growing fetus. These tumors can occur in the ovaries, testes, or other areas of the body and are known for their aggressive nature. Diagnosis typically involves imaging tests and blood tests to check for specific tumor markers, such as alpha-fetoprotein. Treatment usually includes a combination of surgery and chemotherapy, which can be effective in managing the disease. Early detection is crucial for improving outcomes.