[A CASE OF PRIMITIVE NEUROECTODERMAL TUMOR OF THE TESTIS].

A 44-year-old man discovered a swollen right testis more than 4 years earlier. He was brought to our hospital because of abdominal pain and vomiting. Enhanced computed tomography (CT) showed a swollen right testis, lung nodules, and swollen retroperitoneal and mediastinal lymph nodes. The swollen lymph nodes compressed the duodenum, causing ileus. HCG, HCG-β, and AFP levels were normal, but the LDH level was high (2,933 IU/L). A diagnosis of testicular cancer with lung and lymph node metastases was made, and a right orchidectomy was performed. However, the pathological diagnosis was unclear, and it was necessary to consult another pathologist, but this took .6 weeks. While awaiting the pathological diagnosis, the patient was given chemotherapy with two 3-week courses of BEP. On pathological examination, the tumor consisted of small round cells with a rosette-like arrangement. Cartilage and keratinized tissues were also present. Immunohistochemical staining was positive for CD56, synaptophysin, vimentin, GFAP, and CD99 (MIC2), but negative for AE1/AE3, OCT-4, chromogranin, INI-1, and desmin. The patient was then diagnosed as having a primitive neuroectodermal tumor and teratoma. The metastatic lymph nodes decreased in size after chemotherapy; therefore, two further courses of BEP were added. However, CT showed disease progression. The patient refused further therapy and returned home. Eight months later, he was hospitalized because of swollen retroperitoneal and mediastinal lymph nodes and ileus. Despite treatment with radiation therapy, which resulted in decreased lymph nodes, the patient died. This was a very rare case, the first such case in Japan.