Retroperitoneal Teratoma with Malignant Transformation of Primitive Neuroectodermal Tumor
摘要
A 7-month-old girl suffered from abdominal distention with poor appetite for one week. A palpable mass, around 10(superscript *)15 cm was found over left abdomen. The ultrasonography revealed a huge anechoic cyst with septum occupying whole left abdomen. Serum tumor marker studies revealed α-fetoprotein level of 17.92 ng/ml and normal level of β-hCG. Abdominal computed tomography showed a lobulated cyst, 11(superscript *)11(superscript *)14 cm, over left abdomen with calcified and fatty component. Retroperitoneal teratoma was highly suspected and total excision of retroperitoneal tumor was performed. Pathology report revealed a picture of grade Ⅰ immature teratoma. Retroperitoneal tumor was relapsed 6 months later. Open biopsy was performed and pathology report revealed recurrent teratoma with malignant transformation of primitive neuroectodermal tumor (PNET). The patient was then having chemotherapy with JEB proctocol. Although the tumor shrank after the chemotherapy, multiple metastasis was noted 3 months later after chemotherapy. Although the combination chemotherapy and radiotherapy was given, the patient expired two years later. Conclusion: the immature teratoma may transform into PNET and close follow-up after surgical excision is necessary.