Immature teratoma mimicking pulmonary stenosis: a case report

Immature teratoma in a mediastinal location is a rare disease that might present as a valve pathology. Germ cell tumors with mediastinal locations account for up to 6% of immature teratoma cases. We present a case of an immature teratoma located primarily in the anterior mediastinum that manifested solely through symptoms of pulmonary stenosis. We report a case of a 20-year-old white man with an immature teratoma who presented with progressive exertional dyspnea. During a cardiac examination, an ejection systolic murmur was observed, and echocardiography findings at an Emergency Centre revealed high velocity flow at the level of the pulmonary artery, indicating pulmonary stenosis. He was hospitalized in our Cardiology Department for further investigation. A chest X-ray revealed a mediastinal mass, and repeated echocardiography indicated the presence of a large mediastinal mass compressing his main pulmonary artery. Magnetic resonance imaging confirmed the tumor in the mediastinum, and a histopathological diagnosis of immature teratoma was established following biopsy. Immature teratoma causing cardiac-related complaints might shift the diagnosis toward cardiovascular diseases, thus requiring prompt examination by standard and sophisticated methods to clarify the diagnosis.