Table 1.

Pit pattern, microvessel pattern and surface pattern classifications

Classification	Hyperplastic	SSP	Dysplasia	Early invasion (SM1)	Deep invasion (SM2/3)
Kudo	Asteroid or star shaped-pit (type II)	Asteroid or star shaped-pit (type II) or type II-O (open shape)	Tubular or round pit either smaller (IIIs) or larger (IIIL) than regular pits. Gyrus/branched type pits (IV)	Irregular aggregation of type IIIs, IIIL and IV pits (Vi)	Loss of pit pattern, amorphous (Vn) non-structural
Sano	Meshed capillary vessels invisible with NBI (type I)	–	Broader meshed capillary vessels surround mucosal glands (type II)	Broad irregular vessels, unevenly sized and branching (type IIIa)	Avascular appearance due to desmoplastic change in stroma (type IIIb)
NICE NBI	Type I		Type II		Type III
Colour (vs background)	Same or lighter	–	Brown	–	Brown to dark brown
Vessels	None or isolated lacy	–	Brown vessels surround (white) pits	–	Disrupted vessels
Surface	Dark or white uniform spots	–	Tubular or branched	–	Amorphous or absent pattern
WASP ▸ Clouded surface ▸ Indistinct border ▸ Irregular shape ▸ Dark spots inside pits	<2 features present	≥2 features present	<2 features present	–	–
JNET	Type I	Type II	Type IIa	Type IIb	Type III
Vessel pattern	Invisible	Invisible	Regular calibre Meshed pattern	Variable calibre Irregular distribution	Loose vessel areas Interruption of thick vessels
Surface pattern	Regular white or dark spots, similar to surrounding mucosa	Regular white or dark spots, similar to surrounding mucosa	Tubular, branched or papillary	Irregular or obscure	Amorphous areas

JNET, Japan NBI Expert Team; NBI, narrow band imaging; NICE, narrow band imaging international colorectal endoscopic; SM, submucosal invasive cancer; SSP, sessile serrated polyp; WASP, workgroup serrated polyps and polyposis.