Cytoarchitecture of the lamina muscularis mucosae and distribution of the lymphatic vessels in the human stomach

Abstract

The aim of the present study was to clarify the anatomical structure of the lamina muscularis mucosae (LMM) in the human stomach and to correlate it with the lymphatic spread of gastric cancer cells. Human stomachs taken at operation or autopsy were used. The specimens derived from these stomachs were examined by light microscopy immunohistochemistry and scanning electron microscopy (SEM). In the cardia and pyloric wall, bundles of smooth muscle cells of the LMM were relatively loose and thin and formed a reticular configuration. Small lymphatic capillaries (approximately 10-30 μm in diameter) were present directly above the LMM, and relatively large lymphatics (approximately 80-100 μm in diameter) were observed in the submucosal layer and within the LMM. In contrast, the LMM in the fundus, body, and antral wall was composed of tight, thick bundles of smooth muscle cells that ran straight. Large lymphatics were found directly beneath the LMM, but they were few in the lamina propria mucosae. In addition, lymphatics adjacent to veins were also found in the submucosa of the fundus. Structural differences in the LMM of the stomach wall might depend on physiological function. In this study, the relationship between the cytoarchitecture of the LMM or the distribution of lymphatic vessels and cancer invasion is discussed.

Preprocedural prediction of non-curative endoscopic submucosal dissection for early gastric cancer

“…Therefore, EGCs located at the upper/mid third of stomach might be more easily missed or diagnosed later than those in the lower third of stomach. The thickness of the submucosa has been reported to be thinner in the body than at the antrum [17], and the lymphatic capillaries are present just above the muscularis mucosa [18]. These anatomical factors may be associated with the submucosal invasive EGC located at the upper/mid third of the stomach as an increased risk for non-curative endoscopic resection.…”

Lymph node metastasis risk according to the depth of invasion in early gastric cancers confined to the mucosal layer

“…In the stomach, lymphatic vessels originate in the deep LP adjacent to the MM [7,8]. The diameter of lymphatic vessels tends to be larger as they enter the deep LP to the submucosal layer [18]. Thus, lymph node metastasis risk in gastric cancer might be different for cancers invading the LP or the MM because lymphovascular invasion is the most important risk factor in gastric cancer.…”

Numerous lymph node metastases in early gastric cancer without preoperatively enlarged lymph nodes: a case report

“…Several studies have reported the presence of large arteries and lymphatics in the submucosal layer [16]. Our patient had a medical history of endoscopic hemostasis for massive hematemesis, indicating carcinoma invasion below the muscularis mucosae at that time.…”