Schwannoma maligno con diferenciación rabdomioblástica mestastásico a cerebro.

Malignant schwannoma is an uncommon neoplasm, accounting for only 5-10% of all sarcomas. Metastasis from malignant schwannoma are quite rare, usually occurs to the lung, that is the most common site of metastasis, followed by bone and pleura, metastasis to the brain are extremely rare and only 12 cases have been reported in the literature since 1963. Case report:. we report a 47 year old male which 3 years after a diagnosis of schwannoma malignant of humerus, presented metastasis to lung and right pleura and 6 months later presented metastases to the parenchyma of the brain in the right fronto parietal region. The histological sections showed areas with rhabdomyoblastic differentiation. The immunostaining showed immnunoreactive for desmin and myogenin. The final diagnosis was a malignant schwannoma with rhabdomyoblastic differentiation (malignant «triton» tumor). Discussion: few cases of metastasis of malignant schwannoma to the brain have been reported, which were associated with neurofibromatosis type 1. The malignant schwannoma is a highly aggressive tumor with a high rate of local recurrence and poor prognostic. [ABSTRACT FROM AUTHOR]