Retroperitoneal cystic immature teratoma: A case report.

Retroperitoneal cystic immature teratoma (RCIT) is a rare disease. RCITs manifest as solid and cystic masses. In pathological sections, cysts of various sizes, with internal hemorrhage and necrosis, are observed. Components of all germ layer tissue are also observed, the majority of which is located within the endoderm. As the tumor contains undifferentiated immature tissue components, RCITs are also termed malignant teratomas. Immature teratomas grow rapidly, often invading adjacent tissue to cause serious symptoms, and transfer through the blood and lymph vessels, often resulting in glandular cancer. The present study reports the case of an infant with RCIT. The female patient, aged six months and six days, was hospitalized due to an abdominal mass. Physical examination revealed a large mass (10×8 cm) below the xiphoid in the epigastrium. The mass, which ranged from the xiphoid to the umbilical region, was friable, and possessed a smooth surface, clear boundaries and poor activity, without tenderness. Upper abdominal computed tomography (CT) revealed a large, solid, cystic mass in the left, middle and lower retroperitoneum. The patient was admitted to the Yantai Yuhuangding Hospital for surgery. The pre-operative examination was improved following admission by documenting parameters that included the results from routine blood tests, bleeding and clotting times and cardiography. Retroperitoneal tumor resection was then performed. During resection, the tumor was found to originate from the retroperitoneum. As the tumor involved the gastric wall, a section of the gastric wall was resected, in addition to the tumor. The resection surface was yellow and friable. Pathological examination of tumor tissue sections revealed the involvement of immature nerves and mesenchymal components, confirming the diagnosis of a grade II immature teratoma. Subsequent to six months of outpatient follow-up, the patient had recovered well, without recurrence. RCIT is a clinically rare disease, and the present study adds to the current understanding of this rare condition in infants.