Mixed Germ Cell Tumor of the Testis

Mixed germ cell tumors are malignant neoplasms that make up 30% of all testicular germ cell tumors and 70% of all nonseminomatous germ cell tumors. As their name implies, they have more than one germ cell component (excluding seminoma with syncytiotrophoblastic cells), with embryonal carcinoma being the most common component, often combined with teratoma, seminoma, or yolk sac tumor.

The tumors contain areas of calcification, necrosis, hemorrhage, and cystic degeneration, findings that are reflected on imaging. The case above shows a heterogeneous testicular mass with solid and cystic components and fluid-fluid levels.

Patients may present with testicular enlargement with or without pain. Prognosis depends on the element with the worst prognosis.

References

• Adham WK, Raval BK, Uzquiano MC, Lemos LB. Best cases from the AFIP: bilateral testicular tumors: seminoma and mixed germ cell tumor. Radiographics. 2005 May-Jun;25(3):835-9.
• Ueno T, Tanaka YO, Nagata M, Tsunoda H, Anno I, Ishikawa S, Kawai K, Itai Y. Spectrum of germ cell tumors: from head to toe. Radiographics. 2004 Mar-Apr;24(2):387-404. Review.