Hyalinizing trabecular adenoma of the thyroid. Report of two cases, with cytologic, immunohistochemical and ultrastructural studies.

The cytologic, histologic, immunocytochemical and ultrastructural features of 2 cases of hyalinizing trabecular adenoma (HTA) of the thyroid are described. The difficulty of a cytologic diagnosis and the need for an immunohistochemical profile of the lesions for a final histologic diagnosis are emphasized.

Fine needle aspiration cytology in a case of diffuse sclerosing carcinoma of the thyroid.

The fine needle aspiration (FNA) cytologic findings in a rare case of bilateral diffuse sclerosing carcinoma of the thyroid are described. Along with a generally papillary architecture, the FNA biopsy smears showed a number of features not usually seen in thyroid carcinomas: psammoma bodies, an abundance of squamous metaplasia and a dense inflammatory component. The FNA diagnosis was multifocal papillary carcinoma with squamous metaplasia; histopathologic examination made the final diagnosis.

[Cell-block immunocytochemical characterization of effusions. Use of antibody panel: calretinin, Ber-EP4, keratin and CD68]. / Caratterizzazione immunocitochimica dei versamenti su citoincluso. Applicazione del pannello anticorpale: calretinina, Ber-EP4, cheratina e CD68.

An anticorpal panel formed by Calretinin, Ber-EP4, Keratin and CD 68 has been applied to differentiate mesothelial hyperplasia/mesothelioma from metastastic carcinoma in cavity effusions. The study was performed in 86 cases in which paraffinated cell-blocks were obtained. All cases positive for malignancy had histological confirmation. The series included 2 malignant mesothelioma, 54 reactive mesothelial hyperplasia, and 30 metastatic carcinoma. All cases of reactive mesothelial showed strong cytoplasmatic positivity for Calretinin, and hyperplasia negativity for Ber-EP4. The 2 cases of mesothelioma were positive for Calretinin and negative for Ber-EP4. In contrast, all cases of metastatic carcinoma had membrane or cytoplasmatic positivity for Ber-EP4. The sensitivity (100%) and specificity (100%) of reactivity for Calretinin and Ber-EP4 showed that the immunocytochemical results on paraffin embedded material from cavity effusions are very reliable, so that the tested immunocytochemical panel can be useful in cytological differential diagnosis between reactive mesothelial hyperplasia/mesothelioma and metastatic carcinoma.