In a recent case study published in the journal Clinical Endoscopy, a research team from the Department of Internal Medicine at Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology in Korea report a rare case of endometriosis that presented as a sub epithelial stomach tumor.
Endometriosis is characterized by the presence of endometrial glands and stroma in an ectopic location outside of the endometrial cavity. Endometriosis usually occurs inside the pelvic cavity; however, endometriosis appears outside of the pelvic cavity in approximately 10% of all cases.
Frequent locations for endometriosis outside of the pelvic cavity include a variety of tissues and organs, such as the intestines, kidneys, lungs, skin, and pleura, with the exception of the spleen. Endometriosis affects the gastrointestinal tract in 5% of cases, with the sigmoid colon being the most commonly affected location, followed by the rectum.
Since gastric endometriosis is rare, in their case report titled “An Extremely Rare Case of Gastric Subepithelial Tumor: Gastric Endometriosis,” Cheol Woong Choi and colleagues present a case of a 44-year-old woman referred with an asymptomatic gastric mass found during a routine check-up. A few days before her visit, the gastric mass was detected in another hospital. Her medical and family histories were unremarkable. At the time of the initial visit, she had a body temperature of 36.5℃, a pulse rate of 82 beats per minute, a respiratory rate of 18 breaths per minute, and her blood pressure was 110/80 mm Hg.
A subepithelial tumor was observed through gastroduodenoscopy on the lesser curvature of the antrum of the stomach. A computed tomography (CT) of the abdomen showed an approximately 2-cm sized, endophytic, homogeneous, and hypo dense submucosal mass in the posterior wall of the stomach antrum.
Endoscopic ultrasonography (EUS) was performed to assess the gastric wall and evaluate the characteristics of the mass, which revealed a homogenous hypoechoic mass with an irregular margin and some hyperechoic foci. The mucosal and submucosal layers were intact. Therefore, an operable gastrointestinal stromal tumor (GIST) was suspected.
Following the EUS, laparoscopic-assisted distal gastrectomy was performed, with the histopathological evaluation shwoying endometriosis containing endometrial glands and hemosiderin-laden macrophages within the muscular layer near the intramural hemorrhagic cyst, compatible with endometriosis.
The team concluded that gastric endometriosis presenting as a subepithelial tumor is exceptionally rare. This specific case was initially suspected as a subepithelial tumor in order to add to the small but existing body of evidence of such occurrences.