Malignant retroperitoneal paraganglioma with intranuclear vacuoles in a fine needle aspirate. A case report.

The cytologic findings in fine needle aspiration smears and cell blocks from a malignant retroperitoneal paraganglioma with subsequent histologic confirmation are described. The aspirate contained clusters of cells with ill-defined borders, often varied in size, round or oval nuclei and marked anisokaryosis. An unusual feature was the presence of prominent intranuclear vacuoles in some cells. The histologic and ultrastructural findings, as well as the results of histochemical and immunodiagnostic staining, are also presented.