Mediastinal germ cell tumors: a radiologic–pathologic review

Abstract

Germ cell tumors of the mediastinum are histologically identical to those found in the testes and ovaries. Early diagnosis and treatment improve the survival rate. Imaging studies of teratoma demonstrate a rounded, often lobulated heterogeneous mass containing soft tissue elements with fluid and fat attenuation. Calcification is present in 20-43% of cases. Seminomas are large masses of homogeneous soft tissue attenuation. Malignant nonseminomatous germ cell tumors are heterogeneous tumors with irregular borders due to invasion of adjacent structures. CT shows the location and extent of the tumors as well as intrinsic elements including soft tissue, fat, fluid, and calcification. CT is the modality of choice for the diagnostic evaluation of these tumors. MRI reveals masses of heterogeneous signal intensity, is more sensitive in depicting infiltration of the adjacent structures by fat plane obliteration, and is performed as an ancillary study.

Computed tomography and magnetic resonance imaging of mediastinal tumors

“…Areas of degeneration due to hemorrhage and coagulation necrosis may present but are usually limited (49,50) (Fig. 11).…”

“…On CT, the tumors show inhomogeneous soft-tissue density with areas of low attenuation representing cystic necrosis and hemorrhage (50) (Fig. 12).…”

“…On CT and MRI, the tumors typically have homogenous internal attenuation and signal intensity and show minimal enhancement after administration of contrast material. Areas of degeneration due to hemorrhage and coagulation necrosis may present but are usually limited (49,50) (Fig. 11).…”

Primary Small Cell Neuroendocrine Carcinoma of the Mediastinum

“…These tumors may secrete human chorionic gonadotropin and α-fetoprotein. 23 (4) Mediastinal lymphoma most commonly occur in the anterior or middle mediastinum. This usually involves multiple lymph nodes, which are fused together, resulting in mediastinal and paratracheal lymphadenopathy.…”

The Retroconversion of Immature Mediastinal Teratoma with Chemothearpy: A Case Report

“…CT of chest is the first choice for the diagnostic evaluation of immature and mature mediastinal teratoma. It shows tumor location and extention as well as intrinsic elements including soft tissue, fat, fluid and calcification [16]. The mediastinal immature teratoma menifests as a heterogenous mediastinal mass containing soft tissue fluid, fat or calcification or any combination of four.…”