Gastric adenocarcinoma coexisting with a reddish semipedunculated polyp arising from Helicobacter pylori-negative normal gastric mucosa: a report of two cases

Abstract

We experienced two cases of adenocarcinoma coexisting with a hyperplastic polyp arising from Helicobacter pylori-negative normal gastric mucosa. The first case was of a 59-year-old man. Esophagogastroduodenoscopy revealed a protruding lesion measuring 4 mm in diameter on the greater curvature of the middle gastric body. The second case was of a 47-year-old man. Esophagogastroduodenoscopy showed a protruding lesion measuring 5 mm located at the greater curvature of the upper gastric body. The absence of atrophic changes in the entire gastric mucosa was confirmed endoscopically in both cases. Multiple H. pylori tests were all negative. Endoscopically, these protruding lesions appeared as reddish, semipedunculated polyps. Hyperplastic polyps were suspected based on white light endoscopic findings. Magnified endoscopy with narrow band imaging could not predict the coexistence of cancer. However, histopathological examination of the resected specimen revealed focal cancer at the surface of the gastric hyperplastic polyps. Considering the possibility that cancer may be coexisting in polyps, when reddish polyps are detected in H. pylori-negative normal gastric mucosa, it is important to perform a biopsy, or a careful follow-up endoscopy.

Linked Color Imaging Demonstrates Characteristic Findings in Semi-Pedunculated Gastric Adenocarcinoma in Helicobacter pylori-Negative Normal Mucosa

“…8 A recent series reported red and semi-pedunculated gastric adenocarcinomas arising in normal mucosa. 9,10 In this patient, the color and shape of the malignancy seen with white light imaging were similar to those seen in hyperplastic polyps in H. pylori-positive mucosa. However, LCI showed endoscopic findings consistent with a malignant lesion and a background different from hyperplastic polyps.…”

“…These findings of surface pattern have been observed in several patients with similar malignant lesions and play an essential role in distin-guishing this type of cancer from a benign polyp. 9,10 We reported that early gastric cancers show orange-red, orange-white, and purple colors using LCI. 3 It is noted that red cancers imaged with white light imaging change to purple with LCI.…”

Clinicopathological and Endoscopic Features of Raspberry-Shaped Gastric Cancer in Helicobacter pylori-Uninfected Patients

“…Previous studies have classified Hp -uninfected GCs into 4 major histopathological types: signet ring cell carcinomas [6, 7], gastric adenocarcinoma of fundic gland (GA-FG) type [8, 9], gastric adenocarcinoma of fundic gland mucosa (GA-FGM) type [10, 11], and differentiated type GC with low-glade atypia [12]. Recently, gastric adenocarcinoma of foveolar-type (GA-FV), which is diagnosed as a differentiated type GC with low-glade atypia in Hp -uninfected GCs, has newly been categorized as a subtype of raspberry-shaped gastric cancer (RSGC) [13, 14]. We recognize GA-FV as a well-differentiated adenocarcinoma based on the Japanese Classification of Gastric Carcinoma (JCGC), although it has been described as a foveolar-type adenoma by WHO classification [14, 15].…”

Risk factors and clinical correlates of neoplastic transformation in gastric hyperplastic polyps in Chinese patients

“…Whether the presence of AMAG may constitute an additional risk factor for neoplastic change within GHPs remains uncertain. Some case reports have described the probable relationship between GHPs and dysplasia or carcinoma [21][22][23] . Neuroendocrine differentiation occurs in 39.6% of gastric cancer cases and occurs more frequently in poorly differentiated cancers than in well differentiated tumors 24 .…”