대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Ruptured Mediastinal Teratoma

Radiologic Findings

Brief Review

Most common primary germ-cell tumors in the mediastinum are cystic teratomas containing ectodermal, mesodermal, and endodermal derivatives. The presence of thick-walled cysts and fat or calcific densities is highly suggestive of mediastinal teratomas on CT. These tumors rarely rupture into the adjacent structures, such as the pleural space, pericardium, lung parenchyma, or tracheobronchial tree. Proteolytic or digestive enzymes derived from the tumor have been proposed as the cause of tumoral rupture. When the tumor is ruptured, these enzymes can cause inflammation and necrosis of adjacent organs. Prompt treatment of ruptured tumors is necessary because acute respiratory distress can develop. In addition, surgical management of ruptured tumors often is more complicated than that of unruptured tumors because internal components of the teratoma leak into the thoracic cavity, causing inflammation and adhesion. Therefore, preoperative diagnosis of ruptured teratoma is important for deciding the appropriate time for surgery and the plan of surgical approach.
Patients with mediastinal teratomas are usually asymptomatic (up to 53%). Severe symptoms (chest pain, dyspnea, or hemoptysis) were more commonly found in ruptured than in unruptured tumors. All ruptured mediastinal teratomas had a tendency to display inhomogeneity of the internal component, whereas 90% of unruptured masses showed homogenous densities of internal components in each compartment of the mass. Ancillary CT findings (such as a fat-containing mass, consolidation, or atelectasis in the adjacent lung) are important for detecting rupture in the mediastinal teratomas, although associated compressive atelectasis and pneumonitis in the adjacent lung also could be caused by large mass size. Pleural effusion was one of the most common ancillary CT findings (57%) in ruptured mediastinal teratomas. Pericardial effusion, especially in-patients with a teratoma adhering to the pericardium, also appeared to suggest rupture of the tumor into the pericardium.

References

Choi SJ, Lee JS, Song KS, Lim TH. Mediastinal teratoma: CT differentiation of ruptured and unruptured tumors. AJR 1998;171:591-597

Keywords

Mediastinum, Benign tumor,