Categorization of pediatric neoplasms by immunostaining with antiprekeratin and antivimentin antisera.

Forty-six tumors in children were examined using light microscopy and subsequently frozen sections were stained with antiprekeratin and antivimentin antisera, so that the tumors could be classified by tissue of origin. Except for two adrenal cortical carcinomas and four liver tumors, most epithelial neoplasms continued to produce prekeratin filaments, a characteristic of normal epithelial cells. Tumors and cells of epithelial origin did not produce vimentin filaments, whereas normal and neoplastic mesenchymal cells did. Tumors with both epithelial and mesenchymal components produced vimentin filaments in mesenchymal areas and prekeratin in epithelial areas. Tumors of lymphoid origin showed variable production of vimentin filaments, depending on the amount of cell cytoplasm, but did not contain prekeratin filaments. Of the neuroectodermal tumors, only the ganglioneuroma contained vimentin filaments and none contained prekeratin filaments. Thus, antibodies to both prekeratin and vimentin filaments are useful in diagnosing childhood neoplasms and studying their histogenesis.