We established a diagnostic algorithm for RSGLs based on the following endoscopic features (
Figure 6). If RSGL is detected, the first step is to identify the presence of a submucosal tumor shape in WLI. If a submucosal tumor shape is present, the next step is to evaluate the redness of the lesion using WLI. If the redness of the lesion is homogenous, GA-FGM may be diagnosed; if the redness of the lesion is heterogeneous, GA-FG may be diagnosed. If the submucosal tumor shape is absent, the second step is to evaluate the mixed linear or dotted shape of the MCE using WLI. If there is a mixed linear or dotted shape of the MCE, RSBGL may be diagnosed; if there is no mixed linear or dotted shape of MCE, GA-FV/GA-FGM may be diagnosed. According to ME-NBI, if the MV is irregular, a diagnosis of GA-FV/GA-FGM may be made; if the MV is regular/absent, RSBGL may be diagnosed.
Figure 1.
Endoscopic and pathological findings of GA-FV. (a) WLI reveals a reddish superficial elevated lesion, with an approximate size of 5 mm, on the greater curvature of the upper third of the stomach. The MCE shape is only polygonal or curved; (b) ME-NBI shows an irregular MV pattern plus a regular MS pattern with a demarcation line and an irregular inner edge shape of MCE (red arrow); (c, d) Hematoxylin and eosin (H&E) stain. Histological findings of endoscopic mucosal resection specimen indicate well-differentiated adenocarcinoma that mimicked foveolar epithelium in the superficial layer; (e-i) Immunostaining; (e) MUC5AC (gastric foveolar epithelial cell). Diffusely positive; (f) MUC6 (gastric mucous neck cell). Negative; (g) pepsinogen-I (chief cell). Negative; (h) H+/K+-ATPase (parietal cell). Negative; (i) Ki-67 is overexpressed (Labeling index 80%); (j) The structural schema of GA-FV is presented. Original magnification: (c, e-h) ×40, (d, i) x100. [M, Less, 0-I, 5×4 mm, pap, pT1a/M, pUL0, Ly0, V0, pHM0, pVM0].
Figure 1.
Endoscopic and pathological findings of GA-FV. (a) WLI reveals a reddish superficial elevated lesion, with an approximate size of 5 mm, on the greater curvature of the upper third of the stomach. The MCE shape is only polygonal or curved; (b) ME-NBI shows an irregular MV pattern plus a regular MS pattern with a demarcation line and an irregular inner edge shape of MCE (red arrow); (c, d) Hematoxylin and eosin (H&E) stain. Histological findings of endoscopic mucosal resection specimen indicate well-differentiated adenocarcinoma that mimicked foveolar epithelium in the superficial layer; (e-i) Immunostaining; (e) MUC5AC (gastric foveolar epithelial cell). Diffusely positive; (f) MUC6 (gastric mucous neck cell). Negative; (g) pepsinogen-I (chief cell). Negative; (h) H+/K+-ATPase (parietal cell). Negative; (i) Ki-67 is overexpressed (Labeling index 80%); (j) The structural schema of GA-FV is presented. Original magnification: (c, e-h) ×40, (d, i) x100. [M, Less, 0-I, 5×4 mm, pap, pT1a/M, pUL0, Ly0, V0, pHM0, pVM0].
Figure 2.
Endoscopic and pathological findings of GA-FG. (a) WLI reveals a heterogenous reddish protruded lesion with a submucosal tumor shape, with an approximate size of 5 mm, on the greater curvature of the upper third of the stomach; (b) ME-NBI shows an irregular MV pattern plus a regular MS pattern with a demarcation line; (c, d) H&E stain. Histological findings of the endoscopic submucosal dissection specimen indicate well-differentiated adenocarcinoma that mimicked gastric fundic glands structured as irregular branches in the deep layer of the lamina propria mucosa, infiltrating the submucosal layer (300 μm). The superficial layer of the tumor margin is covered with a non-neoplastic epithelium; (e-i) Immunostaining; (e) MUC5AC (gastric foveolar epithelial cell). Negative; (f) MUC6 (gastric mucous neck cell). Positive; (g) pepsinogen-I (chief cell). Diffusely positive; (h) H+/K+-ATPase (parietal cell). Positive; (i) Ki-67 is overexpressed (Labeling index 10%); (j) The structural schema of GA-FG is presented. Original magnification: (c, e-h) ×40, (d, i) x100. [U, Gre, 0-I, 5×4mm, adenocarcinoma of fundic gland type, pT1b1/SM1 (300 μm), pUL0, Ly0, V0, pHM0, pVM0].
Figure 2.
Endoscopic and pathological findings of GA-FG. (a) WLI reveals a heterogenous reddish protruded lesion with a submucosal tumor shape, with an approximate size of 5 mm, on the greater curvature of the upper third of the stomach; (b) ME-NBI shows an irregular MV pattern plus a regular MS pattern with a demarcation line; (c, d) H&E stain. Histological findings of the endoscopic submucosal dissection specimen indicate well-differentiated adenocarcinoma that mimicked gastric fundic glands structured as irregular branches in the deep layer of the lamina propria mucosa, infiltrating the submucosal layer (300 μm). The superficial layer of the tumor margin is covered with a non-neoplastic epithelium; (e-i) Immunostaining; (e) MUC5AC (gastric foveolar epithelial cell). Negative; (f) MUC6 (gastric mucous neck cell). Positive; (g) pepsinogen-I (chief cell). Diffusely positive; (h) H+/K+-ATPase (parietal cell). Positive; (i) Ki-67 is overexpressed (Labeling index 10%); (j) The structural schema of GA-FG is presented. Original magnification: (c, e-h) ×40, (d, i) x100. [U, Gre, 0-I, 5×4mm, adenocarcinoma of fundic gland type, pT1b1/SM1 (300 μm), pUL0, Ly0, V0, pHM0, pVM0].
Figure 3.
Endoscopic and pathological findings of GA-FGM. (a) WLI reveals a homogenous reddish protruded lesion with a submucosal tumor shape, with an approximate size of 8 mm, on the anterior wall of the upper third of the stomach. The MCE shape is both polygonal/curved and linear/dotted; (b) ME-NBI shows a regular MV pattern plus an irregular MS pattern with a demarcation line; (c, d) H&E stain. Histological findings of the endoscopic submucosal dissection specimen indicate well-differentiated adenocarcinoma that mimicked foveolar epithelium in the superficial layer, and mimicked gastric fundic glands structured as irregular branches in the deep layer of the lamina propria mucosa, which infiltrated the submucosal layer (300 μm); (e-i) Immunostaining; (e) MUC5AC (gastric foveolar epithelial cell). Positive; (f) MUC6 (gastric mucous neck cell). Positive; (g) pepsinogen-I (chief cell). Diffusely positive; (h) H+/K+-ATPase (parietal cell). Positive; (i) Ki-67 is overexpressed (Labeling index 20%); (j) The structural schema of GA-FGM is presented. Original magnification: (c, e-h) ×40, (d, i) x100. [U, Gre, 0-I, 8×7mm, tub1, pT1b1/SM1 (300 μm), INFa, pUL0, Ly0, V0, pHM0, pVM0].
Figure 3.
Endoscopic and pathological findings of GA-FGM. (a) WLI reveals a homogenous reddish protruded lesion with a submucosal tumor shape, with an approximate size of 8 mm, on the anterior wall of the upper third of the stomach. The MCE shape is both polygonal/curved and linear/dotted; (b) ME-NBI shows a regular MV pattern plus an irregular MS pattern with a demarcation line; (c, d) H&E stain. Histological findings of the endoscopic submucosal dissection specimen indicate well-differentiated adenocarcinoma that mimicked foveolar epithelium in the superficial layer, and mimicked gastric fundic glands structured as irregular branches in the deep layer of the lamina propria mucosa, which infiltrated the submucosal layer (300 μm); (e-i) Immunostaining; (e) MUC5AC (gastric foveolar epithelial cell). Positive; (f) MUC6 (gastric mucous neck cell). Positive; (g) pepsinogen-I (chief cell). Diffusely positive; (h) H+/K+-ATPase (parietal cell). Positive; (i) Ki-67 is overexpressed (Labeling index 20%); (j) The structural schema of GA-FGM is presented. Original magnification: (c, e-h) ×40, (d, i) x100. [U, Gre, 0-I, 8×7mm, tub1, pT1b1/SM1 (300 μm), INFa, pUL0, Ly0, V0, pHM0, pVM0].
Figure 4.
Endoscopic and pathological findings of HP. (a) WLI reveals a homogenous reddish protruded lesion, with an approximate size of 6 mm, on the greater curvature of the upper third of the stomach. The MCE shape is both polygonal/curved and linear/dotted; (b) ME-NBI shows absent MV pattern plus a regular MS pattern with a demarcation line; (c) H&E stain. Histological findings of the biopsy specimen indicate foveolar epithelial hyperplasia with cystic dilatations and edema and inflammation of lamina propria; (d-h) Immunostaining; (d) MUC5AC (gastric foveolar epithelial cell). Positive; (e) MUC6 (gastric mucous neck cell). Negative; (f) pepsinogen-I (chief cell). Negative; (g) H+/K+-ATPase (parietal cell). Negative; (h) Ki-67 is not overexpressed. Original magnification: (c-h) x100.
Figure 4.
Endoscopic and pathological findings of HP. (a) WLI reveals a homogenous reddish protruded lesion, with an approximate size of 6 mm, on the greater curvature of the upper third of the stomach. The MCE shape is both polygonal/curved and linear/dotted; (b) ME-NBI shows absent MV pattern plus a regular MS pattern with a demarcation line; (c) H&E stain. Histological findings of the biopsy specimen indicate foveolar epithelial hyperplasia with cystic dilatations and edema and inflammation of lamina propria; (d-h) Immunostaining; (d) MUC5AC (gastric foveolar epithelial cell). Positive; (e) MUC6 (gastric mucous neck cell). Negative; (f) pepsinogen-I (chief cell). Negative; (g) H+/K+-ATPase (parietal cell). Negative; (h) Ki-67 is not overexpressed. Original magnification: (c-h) x100.
Figure 5.
Endoscopic and pathological findings of PPI-L with low-grade dysplasia. (a) WLI reveals a homogenous reddish protruded lesion, with an approximate size of 6 mm, on the greater curvature of the upper third of the stomach. The MCE shape is both polygonal/curved and linear/dotted; (b) ME-NBI shows a regular MV pattern plus a regular MS pattern with a demarcation line; (c-d) H&E stain. Histological findings of the CFP specimen indicate parietal cell hyperplasia and protrusion, dilation and elongation of the foveolar epithelium, and vascularity of stroma. The surface of the PPI-L shows low-grade dysplasia; (e-i) Immunostaining; (e) MUC5AC (gastric foveolar epithelial cell). Positive; (f) MUC6 (gastric mucous neck cell). Negative; (g) pepsinogen-I (chief cell). Negative; (h) H+/K+-ATPase (parietal cell). Negative; (i) Ki-67 is overexpressed (Labeling index 80%). Original magnification: (c-i) x100.
Figure 5.
Endoscopic and pathological findings of PPI-L with low-grade dysplasia. (a) WLI reveals a homogenous reddish protruded lesion, with an approximate size of 6 mm, on the greater curvature of the upper third of the stomach. The MCE shape is both polygonal/curved and linear/dotted; (b) ME-NBI shows a regular MV pattern plus a regular MS pattern with a demarcation line; (c-d) H&E stain. Histological findings of the CFP specimen indicate parietal cell hyperplasia and protrusion, dilation and elongation of the foveolar epithelium, and vascularity of stroma. The surface of the PPI-L shows low-grade dysplasia; (e-i) Immunostaining; (e) MUC5AC (gastric foveolar epithelial cell). Positive; (f) MUC6 (gastric mucous neck cell). Negative; (g) pepsinogen-I (chief cell). Negative; (h) H+/K+-ATPase (parietal cell). Negative; (i) Ki-67 is overexpressed (Labeling index 80%). Original magnification: (c-i) x100.
Figure 6.
Diagnostic algorithm of RSGL.
Figure 6.
Diagnostic algorithm of RSGL.