Table 1.

Endoscopic Features and Definitions of Sessile Serrated Adenomas

Feature	Definition	Image examples from Fig. 1	Reference
Indistinctive borders	Vague demarcation of a border of a lesion	B, C, D	Hazewinkel et al. (2013) [15]
Irregular shape	An asymmetric shape in contrast to the oval, circular shape of small hyperplastic polyps and conventional adenomas	B, C, E, F	Hazewinkel et al. (2013) [15]
Rim of debris	A conspicuous ring of debris/bubbles encircling ≥25% of the lesion	A, C	Tadepalli et al. (2011) [14]
Cloud-like surface	A bumpy, soft-looking nodular surface resembling a cumulus cloud	B, F	Hazewinkel et al. (2013) [15]
Mucous cap	Focal collection of mucus (clear, bile stained, or debris stained) on the mucosal surface that can be washed off with irrigation	A, E	Tadepalli et al. (2011) [14]
Nodular surface	Focal, subtle irregularity or bumpiness of the mucosal surface	E	Tadepalli et al. (2011) [14]
Absence of surface vessels	Small superficial vessels or telangiectasias occasionally seen on the surface of particular distal hyperplastic polyps	A, B, D, G	Hazewinkel et al. (2013) [15]
Dark spots	Small red dots inside the open crypts on high-resolution white-light endoscopy	F, G	Hazewinkel et al. (2013) [15]