Introduction
The incidence of testicular germ cell tumors has increased from 5.7 to 6.8 cases per 100,000 individuals between 1992 and 2009 [1]. Testicular yolk sac tumors are rare in nature. They are a type of non-seminomatous germ cell tumors. In adults, yolk sac tissue in germ cell tumors is usually seen in combination with other types of germ cell tumors. They usually present during the second and third decades of life. Distant disease is also more frequent in post pubertal patients than the pediatric patients [2]. These yolk sac tumors are dangerous and without treatment, lead to rapid deterioration of clinical status.
Wang et al. [3] reported in 2015 that during their literature search, they only found < 20 cases of pure yolk sac tumors in adults. On further literature search, we found 2 more case reports published after 2015 reporting a case of pure yolk sac tumor [4] [5]. We report here a case of gonadal primary adult yolk sac tumor in a 40-year-old male.