[A case of primitive neuroectodermal tumor in the chest wall ("Askin's tumor")]

We report a case of Askin's tumor, primitive neuroectodermal tumor (PNET) in the chest wall, with review of reported cases of PNET. Our case was the ninth of Askin's tumor and the 36th of PNET in Japan. A 12-year-old girl was hospitalized because of a large right intrathoracic mass. The serum neuron-specific enolase (NSE) was 11.4 ng/ml, slightly increased, and the urinary excretion of catecholamine metabolites was normal. The needle biopsy specimens were diagnosed as small round cell sarcoma. At surgery we found an encapsulated multilobular mass in the region. The chest wall was resected partially to extirpate it completely. Its macroscopic and microscopic features were almost similar to the description of Askin et al. The immunohistochemical staining of the cells was positive for NSE, strongly suggesting the neurogenic origin. After surgery, intensive chemotherapy with autologous bone marrow transplant was performed, and she has been living without sign of recurrence for two years.