**6.1 Endoscopic features**

On endoscopy, HGMP/CIP appears as salmon or velvety colored patch that is clearly distinct to the slatey white esophageal squamous cell mucosa (Figure 7). A majority of HGMP/CIP is round or ovoid. Some can be elongated with the maximal dimension in the longitudinal direction. Rarely, HGMP/CIP can be so big that they cover almost or the entire circumference of the esophagus. Smaller patches tend to be round or oval, are usually elevated or flat with smooth texture and white edges. Larger patches tend to be depressed on maximal insufflations during endoscopic examination and are ovoid or elongated with jagged edges and nodular surface textures. Occasionally, inflammatory changes similar to those observed in reflux esophagitis can be seen at the edges. Most are single patch and


Table 2. Prevalence of symptoms reported to be associated with HGMP/CIP

Heterotopic Gastric Mucosal Patch of the Proximal Esophagus 135

a) b)

c) d)

e)

Fig. 7. Endoscopic images showing different HGMPs; a) a large depressed patch with coarse surface texture with another patch located on the opposite wall, b) two small patch with smooth surface texture, one elevated and the other flat, c) a large slightly depressed patch with coarse surface texture on the right lateral wall, d) two round elevated patch with white edges and smooth surface and associated venous bled, and e) a small flat round patch with smooth surface texture located above the gastroesophageal junction. All the patches shown

stained positive for CK7 and CK20 with characteristics pattern

in patients with multiple patches, they tend to be found in close proximity, above or below forming columns or on the opposite side (kissing patches). It is uncertain whether the size of HGMP/CIP may change with time. One study reported that the size of a HGMP/CIP decreased during subsequent endoscopy whilst on acid suppression treatment (Chong & Jalihal, 2006). Healing of surrounding inflammation may account for this observation. Associated findings include elevated whitish nodules that do not have the characteristic salmon colored mucosa. In elderly patients, venous bled or hematoma can also be found. To date, the profiles of HGMP/CIP have not been properly studied. Interestingly, HGM can also be found in other parts of the esophagus, mid esophagus and above the gastroesophageal junction (Borhan-Manesh & Franum, 1991; Katsanos et al., 2010) (Figure 7e). It is likely that the overall acid production from the HGMP/CIP is less than that seen in gastroesophageal reflux disease affecting the gastroesophageal junction. Acid related

injuries can be seen in the patch and the surrounding esophageal squamous mucosa. Inflammatory macroscopic changes visible during endoscopy or microscopic changes only visible on histological examinations resembling those seen in reflux esophagitis have been described.
