The endoscopic diagnosis of Barrett’s esophagus and associated neoplasia requires a standardized endoscopic approach [7, 9]:

Barrett’s esophagus:

The Prague or CE classification describes the amount of metaplastic epithelium within the lower esophagus (Fig. 7.1).

The key steps are:

Barrett’s associated neoplasia:

Surveillance endoscopy for BE should be performed after a 4-week course of proton pump inhibitor therapy for better detection of Barrett’s extent and neoplastic lesions, in particular when using chromoendoscopy for detection of SIM (sensitivity 98 %, specificity only 61 % without PPI pretreatment) [14].

Several enhanced imaging techniques can be used to differentiate between SIM and gastric-type epithelium within columnar-lined lower esophagus (Table 7.2; Fig. 7.2a–d). Chromoendoscopy with acetic acid, indigo carmine (or methylene blue), can be used to unmask villous- or gyrous-type mucosal pattern.

Acetic acid shows accuracy between 52 and 92 %. Methylene blue seems not to be efficient identifying SIM based on a meta-analysis from 2009 [15]. Few studies indicate usefulness of indigo carmine for the detection of SIM (accuracy 71–97 %) [9, 16].

NBI can also be used to identify SIM. Non-dysplastic SIM is characterized by two subtypes: villous/ridge pits with regular microsurface pattern (RMSP) (Fig. 7.2b–d) or absent surface pattern (AMSP) with arborized submucosal veins (Fig. 7.2e; Table 7.2) [12, 17, 18].

The majority (85 %) of early malignant Barrett’s neoplasias are diminutive and flat lesions (0-IIa,b,c) and are difficult to detect [19, 20].

Methylene blue staining seems not to be effective diagnosing Barrett’s associated neoplasia [13, 15]. However, acetic acid-enhanced magnification endoscopy can be used to unmask irregular microsurface pattern (MSP) of subtle neoplastic areas (Table 7.2; Fig. 7.2f, g). The surface pattern is best visualized after spraying of 1.5 % acetic acid. The MSP of neoplasias is irregular villous/gyrous, often micrified (Fig. 4.​12b, d) or nonstructured with irregular MVP, often mixed with remnants of type I pattern or squamous epithelium [21]. NBI in combination with magnification also visualizes the microvascular pattern (MVP) of the mucosa [16]. Characteristic NBI features of Barrett’s associated neoplasias are distorted microsurface with irregular microvasculature [12, 17] (Table 7.2; Fig. 7.2f, g and 7.3).

Overall, enhanced magnification endoscopy including inspection with NBI achieves about 80 % sensitivity for detection of HGIN and early adenocarcinoma in BE in experienced hands [22].

Nonstructured, irregular MSP combined with irregular MVP probably predicts deeply invasive cancer in BE [21], but the diagnostic accuracy has not yet been proven for deep submucosal invasion in early Barrett’s cancer (Table 7.2).

Regular MSP of Barrett epithelium has well been characterized by the group in Nottingham using the Japanese RBG-rotating wheel imaging system (comp. Chap. 4) with superior image resolution as compared to standard Western imaging systems (Fig. 7.2, RMSP and AMSP images reduced in size, from Nottingham classification [12], permission granted by Blackwell Publishing Ltd.). So far, the diagnostic accuracy of the classifications for Barrett’s mucosa and neoplasias has not been prospectively evaluated.

However, the association has been convincing between deep submucosal invasion and macroscopic types of lesions [19] (Table 7.3). In a large prospective series of 380 Barrett’s neoplastic lesions, most of the HGIN lesions were type 0-IIb (70 %) and 0-IIa (17 %). The likelihood for submucosal invasive early cancer was lowest for lesions type 0-IIb (3 %) and progressively increased for lesions type 0-I (10 %), 0-IIa (14 %), IIa + c (18 %), and 0-IIc (24 %) [19]. Due to difficult recording at this location, high-frequency EUS (20–30 MHz) was not reliable enough to detect submucosal invasion in neoplastic Barrett’s lesions (sensitivity only 27 %) [23].