Table 2. Esophageal EC classification.

Classification	Structure	Nuclei
EC1 (non-neoplastic)
a (normal)	Regularly arranged large rhomboid-shaped cells	Uniform pattern of small, round nuclei with homogenous size located in the center
b (esophagitis)	Edges of the cells are slightly blunted, making the cells look rounded rather than rhomboid
EC2 (intraepithelial neoplasia)	Increase in cellular density compared to EC1; cellular structure can still be identified	Centrally located round nuclei which may remain small or mildly enlarged
EC3 (squamous cell carcinoma)	Significant increase in cellular density with loss of cellular structure	Significant swelling of the nuclei with heterogeneity in size and shape

EC, endocytoscopy.