ALIGNANT PERIPHERAL NERVE SHEATH TUMOR (A CASE REPORT)

Malignant peripheral nerve sheath tumor (MPNST) is an aggressive neoplasm of neural origin. It is a rare neoplasm of childhood, accounting for less than 5% of all cases.
In 1994 a 29 months old boy was admitted to the Mofid Hospital with complaints of fever, dyspnea and respiratory distress.
After performing all the necessary clinical and labratory tests a large mass in the upper posterior mediastinum was detected. The tumor was resected.
Pathological examination of the tumor showed a malignant neoplastic tissue composed of round atypical cells with hyperchromatic and vesicular nuclei and eosinophilic cytoplasm similar to rhabdomyoblasts pseudorossettes and areas of necrosis and hemorrhage were evident.
On immunohistochemical study, the tumor cells were positive for S100 protein, NSE, vim entin, keratin and EMA.
Diagnosis of MPNST was confirmed by clinical manifestation, pathologic findings and immunohistochemical studies.