Cytology features: very cellular smears, with absent colloid, but some amorphous blueish material (probable amyloid), not to be confused with "chewing gum" colloid. The tumoral cells occur mostly as dispersed single cells, with ovoid or triangular shape. Their cytoplasm have a finely pink granular material. Histology revealed a typical medullary carcinoma of the thyroid. (H&E staining)Click here to see the histology pictures