[The growing teratoma syndrome: report of a case].

A 32-year-old man presented with a swelling of the left testis, for which he underwent high inguinal orchiectomy. Histopathological examination of the specimen revealed teratocarcinoma. Further evaluation revealed no metastasis (stage I), and he was followed-up by monthly examination without prophylactic chemotherapy (surveillance). Thirteen months after orchiectomy, AFP and hCG-beta were elevated at 133.8 ng/ml and 0.8 ng/ml respectively. Abdominal CT scan revealed para-aortic masses of recurrent tumor. Although the AFP and hCG-beta levels markedly declined after five courses of COMPE (CDDP, VCR, MTX, PEP, Etoposide) chemotherapy, the retroperitoneal masses had further enlarged and had undergone cystic change. Excision of the residual tumors was performed, and microscopic examination of specimens revealed mature teratoma without malignant components. The diagnosis of the growing teratoma syndrome was therefore made. The growing teratoma syndrome occurs in nonseminomatous testicular germ cell tumors following chemotherapy and is characterized by enlargement of metastatic lesions with normal tumor marker levels. Total surgical resection of the mass yields good results, and tumor is unresponsive to chemotherapy. Early recognition of this syndrome is important for successful treatment.