Nuclear and cytoplasmic characteristics of CECs. 2A: Malignant-appearing cell with nucleomegaly (>3× pore size), increased N/C ratio (>0.75), marked nuclear irregularity, and hyperchromasia. 2B: Cells demonstrating nucleomegaly, irregular nuclear borders, and marked anisonucleosis (>2× difference in nuclear size), but no visible nucleoli. 2C: Cluster of cells with increased N/C ratio and visible, but non-prominent nucleoli. 2D: groups of cells with increased N/C ratio and prominent nucleoli.