Tumors may show one type of differentiation or combinations of different types. Similar tumors arise in the mediastinum from aberrant totipotential cells. When combinations exist, each component should be listed and quantified. Risk factors include cryptorchism. Hematogenous metastases usually go to lungs, liver, brain, or bones.
Therapy consists of orchiectomy and high ligation of the spermatic cord.
Treatment for seminomas includes additional radiation to the retroperitoneum. I disease include extension of tumor through the testicular capsule, Leydig cell hyperplasia away from tumor, and vascular invasion. Patterns consist of sheets, papillae, or glands. They show varied types of differentiation along 2 or more germ lines. Nerve, cartilage, and epithelium are the most frequent tissues seen.