Adrenal schwannoma with apparent uptake of immunoglobulins.

Schwannoma, a rare tumor of the adrenal gland, was an incidental finding in a 63-year-old woman who had no endocrine symptoms. In addition to the usual light and electron microscopic and immunohistochemical features of a schwannoma, the tumor contained large granular cells and a stroma rich in lymphocytes and plasma cells. The tumor cells appeared on ultrastructural examination to incorporate proteinaceous material by endocytosis into large lysosomal bodies and on immunocytologic studies; the presence of immunoglobulins was noted within the cytoplasm. The apparent massive uptake of immunoglobulins by tumor cells suggests a direct interaction between host and the tumor.