Introduction: Mediastinal mature teratoma is a benign, slow-growing tumor typically affecting 20- to 40-year-old adults. Fluid examination from the cystic masses rarely shows enzymatic activity as we describe in this report.
Case presentation: We report a case of a giant mediastinal germ cell tumor (measuring 15 cm × 14 cm × 8 cm) detected in a 35-year-old Caucasian woman. Microscopic examination showed that the lesion resembled a mature cystic teratoma with areas of pancreatic tissue with mature ductal and acinar structures intermixed with islets of Langerhans. Fluid from the cysts in the mass was examined after removal showed amylase activity of 599 U/l despite normal serum levels. The post-operative period was free of complications, and the patient was discharged on post-operative day 10.
Conclusion: Complete surgical removal is the treatment of choice for mature cystic teratomas, with optimal results and acceptable surgical risk. Exocrine pancreatic function may be an aid to pre-operative or intra-operative diagnosis; however, these findings have no impact on survival or the therapeutic pathway.