Squamous Metaplasia of the Stomach Associated with Lymphoma Infiltration

Abstract

We herein report a patient who presented with follicular lymphoma. Although the stomach was initially intact, mucosal redness and multiple erosions appeared in the gastric body owing to infiltration of the follicular lymphoma cells. Subsequently, a slightly depressed, white area lacking gastric mucosal structure was detected in the lesser curvature of the gastric cardia and body, where lymphoma cell infiltration was also pathologically observed beneath the stratified squamous epithelium. This case indicated that, although infrequent, prolonged mucosal injury owing to lymphoma infiltration can cause squamous metaplasia in the stomach.

Gastric squamous metaplasia observed by image‐enhanced endoscopy

“…According to previous studies, gastric squamous metaplasia appears as white or pale mucosal areas mainly located in the gastric cardia and antrum, with lesions that are slightly depressed when sprayed with indigo carmine (Table 1). 1–4 In addition to these findings, the present case's metaplasia was not pathologically continuous with the squamous epithelium of the esophagus. Instead, gastric mucosa was observed between the metaplasia and the esophageal squamous epithelium of the esophagus.…”

“…Although gastric squamous metaplasia has previously been reported in patients with peptic ulcer, tuberculosis, syphilis, corrosive gastritis, pernicious anemia, and aberrant pancreas, the detailed mechanism of how gastric squamous metaplasia develops is unclear. Squamous metaplasia located in other organs such as the lower respiratory tract, bladder, and uterus has also been observed in patients with chronic inflammation and mechanical irritation 1 . Therefore, the development of gastric squamous metaplasia may be related to long‐term gastric mucosal inflammation induced by H. pylori infection, medication, and radiation.…”

“…Squamous metaplasia located in other organs such as the lower respiratory tract, bladder, and uterus has also been observed in patients with chronic inflammation and mechanical irritation. 1 Therefore, the development of gastric squamous meta-plasia may be related to long-term gastric mucosal inflammation induced by H. pylori infection, medication, and radiation. In fact, an animal model showed that gastric squamous metaplasia can develop following inflammation induced by injection of pyrogallic acid and methylcholanthrene.…”

“…Gastric squamous metaplasia is a relatively rare type of metaplasia observed in the stomach (Table 1). 1–4 The endoscopic appearance of gastric squamous metaplasia is whitish depressed lesions mainly located in the gastric cardia and antrum 1–4 . The etiology of gastric squamous metaplasia remains unclear, and it is important to differentially diagnose it from neoplastic lesions and ulcerative diseases.…”