Teratomas, which is derived from the Greek word "teraton" meaning monster, are tumors comprising more than a single cell type derived from more than one germ layer. Although intrathoracic teratomas are frequent, benign intrapulmonary teratomas seldom occur.
A case of giant intrapulmonary mature teratoma is reported in a 59 year-old female. The lesion was incidentally seen on the chest radiograph as an elevated right hemi-diaphragm during her routine pre-employment medical examination. The patient remained asymptomatic. Chest CT scan showed a giant cystic mass on the right hemithorax. The patient underwent right posterolateral thoracotomy, with excision of the tumor. Adherence to the right main bronchus was present with compression of the right lower lobe, but no fistulation noted. Histopathologic exam revealed mature cystic teratoma.
Teratomas may present with a great variety of clinical and radiological features. However, in some cases, they are clinically silent and represent incidental findings from routine diagnostic examinations.