Fig. 2

a Photograph of surgery with midline incision. The blue arrow indicates the tumor and uterus-like structure in the right pelvis. b Specimens resected by surgery. Uterus-like structure (red arrow) and ruptured tumor (blue arrow) Pathology of the tumor: c Yolk-sac tumors: Loose network of anastomosing channels that focally expand to form variably sized cysts (H&E, X100). d The high-power magnification image from c (red rectangular box) shows that the cysts of yolk sac tumors are lining with transparent or flat atypical epithelium (H&E, X400). e Seminoma: low-power magnification showing nests of primitive germ cells involved by sex cord cells and hyaline basal membrane material. f The high-power magnification image from e (red rectangular box) shows that the tumor cells are round or polygon shaped. The tumor cells had clear cytoplasm and large nuclei. The nuclear membrane and chromatin are bulky, and mitotic phenomena are rare on imaging (H&E, X400)