DIAGNOSIS AND MANAGEMENT OF MALIGNANT PERIRENAL SCHWANNOMA

Malignant retroperitoneal schwannoma is an extremely rare tumor, with only six cases previously reported occurring in the perirenal space. W e herein report the seventh case. A 50-year-old woman presented with a n abdominal. mass suggestive of renal cell carcinoma by standard preop erative evaluation. The tumor required surgical exploration and pathol ogic evaluation for diagnosis. The final histologic diagnosis was made with the aid of electron microscopy and immunohistochemical staining with antibodies for S-100 protein.