Pyloric-gland adenoma of the stomach: case report of a rare tumor successfully treated with endoscopic submucosal dissection

A 79-year-old woman underwent gastroduodenoscopy because of anemia. A gastric polyp was diagnosed as an incidental finding. The polyp was located in the gastric antrum and measured about 2 cm ([Fig. 1]). It was of a hard consistency, with bridging folds and a positive lifting sign. The overlying mucosa was intact. Using the narrow-band imaging technique the tumor was seen to have asteroid-shaped mucosal pits and no vascular abnormalities suggestive of malignancy ([Fig. 2]). Biopsies were taken and showed chronic, Helicobacter-pylori-negative gastritis. Endoscopic ultrasonography was performed and showed an echogenic nodule within the submucosa ([Fig. 3]). For diagnostic and therapeutic purposes we decided to remove the tumor and performed an endoscopic submucosal dissection ([Fig. 4]). The histological examination revealed an adenoma of the pyloric-gland type. There was no evidence of malignant transformation and the resection was complete ([Fig. 5]).

Fig. 1 Endoscopic view of the tumor.

Fig. 2 Tumor as visualized using the narrow-band imaging technique.

Fig. 3 Endoscopic ultrasonography shows an echogenic tumor within the submucosa.

Fig. 4 Endoscopic submucosal dissection of the tumor. After lifting of the tumor by submucosal injection, circumferential incision with submucosal dissection of the tumor is performed.

Fig. 5 a, b Histological sections of the tumor show closely packed pyloric-type glands.

Pyloric-gland-type adenoma of the stomach is a recently described and rare gastric tumor [1] [2]. Apart from case reports, few clinical data and so far only one larger-scale analysis [3] have been published. The name of the tumor reflects its histological resemblance to deep mucoid glands of the gastric mucosa found near the pylorus (‘pyloric-type glands’), and immunohistochemically it is strongly positive for mucin 6. Pyloric-gland adenomas are mainly located in the stomach [3], but they can be found anywhere in the entire gastrointestinal tract and have been described in heterotopic gastric mucosa of duodenum and rectum, in the pancreas, gallbladder, and bile duct, the esophagus and even the uterine cervix. They occur more frequently in women and in old age. Their clinical significance is shown by their 30 % rate of malignant transformation. They are considered to be precancerous lesions and endoscopic removal is indicated [4] [5]. As described in our report, endoscopic submucosal dissection seems to be a highly effective and safe technique.

Endoscopy_UCTN_Code_CCL_1AB_2AD_3AB

References

• 1 Borchard F, Ghanei A, Koldovsky U. et al . Gastrale Differenzierung in Adenomen der Magenschleimhaut; immunhistochemische und elektronenmikroskopische Untersuchungen.  Verh Dtsch Ges Path. 1990;  74 528
• 2 Watanabe H, Jass J R, Sobin L H. Histological typing of oesophageal and gastric tumours. Berlin Heidelberg New York; Springer 1990
• 3 Vieth M, Kushima R, Borchard F. et al . Pyloric gland adenoma: a clinico-pathological analysis of 90 cases.  Virchows Arch. 2003;  442 317-321
• 4 Oberhuber G, Stolte M. Gastric polyps: an update of their pathology and biological significance.  Virchows Arch. 2000;  437 581-590
• 5 Schmitz J M, Stolte M. Gastric polyps as precancerous lesions.  Gastrointest Endosc Clin North Am. 1997;  7 29-46