Grimelius stain for cytodiagnosis of carcinoid tumor

The Grimelius stain is a valuable histochemical method for detecting the specific intracytoplasmic secretory granules of carcinoid tumors. The usefulness of this argyrophilic technique for aspiration biopsy cytology (ABC) specimens was studied by the histologic staining procedure. Aspirates from a metastatic intra-abdominal neoplasm, morphologically suggestive of carcinoid tumor and from a control specimen were restained according to the Grimelius method. Diffuse cytoplasmic argyrophilia was observed in both. The application of Grimelius silver stain to cytology specimens enhances diagnostic accuracy in the evaluation of a suspected carcinoid tumor.