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Tumors of the ovary have been described in many species and are considered to originate from 3 ovarian cell types with distinct embryologic origins: epithelial tumors of Mullerian origin (adenoma or carcinoma), sex cord stromal tumors (e.g., granulosa cell tumor and thecoma-fibroma), and germ cell tumors (dysgerminoma, teratoma, yolk sac tumors).2 Germ cell tumors are a heterogeneous group of neoplasms and can occur in pure form or mixed, including more than 1 germ cell component.16 Mixed germ cell tumors of the gonad are rare entities and, to the authors ’ knowledge, in the veteri-nary literature have only been described in the ovary of 1 female cynomolgus macaque.14 Extragonadal germ cell tumors are also rare and have been described almost exclu-sively in the suprasellar region of the brain of the dog13 and in the eye of a dog.