Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Mature cystic teratoma
- Radiologic Findings
- Chest radiograph shows a mediastinal mass manifesting as bulging of right cardiac border with right pleural effusion. MR images show a multiloculated cystic mass with heterogeneous high-signal-intensity areas on T1- and T2-weighted images. Diffusion weighted MR images show no diffusion restriction. Contrast-enhanced T1-weighted images with fat saturation show peripheral and septal enhancement. Chemical shift images show an area of signal drop on opposed phase images. The patient underwent mediastinal mass excision. Photomicrograph of the surgical specimen shows a mature cystic teratoma containing skin, cartilage, fat tissue, and salivary gland. Preoperative CT images show a heterogeneous anterior mediastinal mass with areas of fat, fluid attenuation, and thin soft-tissue septae.
Opposed phase
- Brief Review
- Mature cystic teratoma is the most common benign mediastinal germ cell neoplasm (60-70%). It is composed of well-differentiated benign tissue from at least two of the three germ cell layers, which are ectoderm (skin and hair), mesoderm, and endoderm. Cyst formation is typical, and cysts are usually lined by tall, mucus-secreting epithelial cells. Patients with mediastinal mature cystic teratoma are ususally asymptomatic, but large size and malignant component can cause symptoms, such as cough, dyspnea, chest pain, upper respiratory complaints, and fever.
On radiography, mature cystic teratomas usually appear as sharply marginated, round or lobulated anterior mediastinal mass that may extend to one side of the midline. Calcification, ossification, or even teeth may be visible. At CT, these tumors appear as heterogeneous and well-defined masses with walls of variable thickness that may enhance. In 15% of cases, teratomas consist of only cystic portion that contains neither fat nor calcification. A fat-fluid level within the tumors is seen less frequently, but it is a highly specific finding. On MR, mature cystic teratomas appear as heterogeneous mediastinal mass containing a variable proportion of fat, fluid, soft tissue, and calcification. A fat-saturation MR imaging technique (phase-shift gradient-echo imaging or proton-selective fat-saturation imaging) can be used to detect fat.
- References
- 1. Jeung MY, et al. Imaging of cystic masses of the mediastinum. Radiographics. 2002;22:S79-S93.
2. Choi SJ, Lee JS, Song KS et al. Mediastinal teratoma: CT differentiation of ruptured and unruptured tumors. AJR Am J Roentgenol. 1998;171 (3): 591-4.
- Keywords
- Mature Cystic Teratoma , anterior mediastinum,