[Cytologic diagnosis and ultrastructure of follicular carcinoma of the thyroid].

A comparative study of aspiration cytology, histology and ultrastructure was made in 8 cases of follicular carcinoma of thyroid and 41 cases of benign thyroid disease. The three main ultrastructural features of nuclei observed in papillary carcinoma of thyroid were also demonstrated in follicular carcinoma. The corresponding appearances of these features (i.e. irregular nuclear grooves and rock-like nuclei the ground-glass appearance of nucleus and the intranuclear eosinophilic globular bodies) were also seen in aspiration cytology. The rock-like nuclei and intranuclear eosinophilic globular bodies are of great value for cytologic diagnosis of thyroid carcinoma and early malignant change of thyroid diseases.