Signs of acute phase of hyperthyroidism are missing. Follicular cells occur dissociated and not in monolayered sheets, vacuolization is minimal. On the other hand thyrocytes exhibit not only anisonucleosis but pleomorphism is present, as well.

This patient was treated for hyperthyoidism for 15 months and was euthyroid at the time of present investigation. Her cytological pattern does not differ from acute phase of hyperthyroidism.