A Case of Duodenal Traditional Serrated Adenoma Manifested as Gastrointestinal Bleeding

Abstract

Traditional serrated adenoma(TSA) is one of subtypes of serrated polyp. Although serrated polyps are usually found in colorectum, they are also detected in upper gastrointestinal tracts. Serrated adenomas of duodenum are very rare and asymptomatic in previously reported cases. However, we experienced a case of duodenal serrated adenoma with bleeding which was diagnosed and treated endoscopically. An 80-years-old-female visited the emergency department due to hematochezia. The laboratory result showed that hemoglobin was 4.2g/dl and iron deficiency anemia. For evaluation of gastrointestinal bleeding, the patient underwent esophagogastroduodenoscopy(EGD) and colonoscopy. The result of EGD was atrophic change and intestinal metaplasia. The colonoscopy showed hyperplastic polyps at ascending colon. Abdominal computer tomography(CT) showed a 1.8cm lobular enhancing nodule at duodenojejunal junction. After she underwent capsule endoscopy, we found a pedunculated polyp at distal duodenum. For further evaluation, we used a colonoscopy to approach the duodenojejunal junction because upper endoscopy could not reach the polyp. A 2.5cm sized lobulating pedunculated polyp was found at 4th portion of duodenum and there was fresh blood near the polyp.(Fig. 1) We considered the polyp as the cause of anemia and bleeding, we recommended her to resect the polyp. We planned to use a detachable snare during polypetomy for the prevention of bleeding and successfully removed the polyp without any adverse event.(Fig. 2) The final pathology result was a traditional serrated adenoma.(Fig. 3) After polypectomy, the patient did not show any bleeding sign. The serrated adenomas are precursors of colorectal cancer and serrated pathway is related with 15% of all colorectal cancer. The prevalence of serrated adenomas of small intestine is very rare and their clinical features are insufficiently known. Based on previous report, traditional serrated adenoma of upper digestive tract showed aggressive behavior with high malignant potential and should be resected for the prevention of cancer progression. Serrated lesions of duodenum are usually found in the bulb and 2nd portion. Our case showed a relatively large size and location in the distal part of duodenum that could not be reached by upper endoscopy. A Delay in detection might cause size increasing and bleeding. To our knowledge, this is the first case of duodenal traditional serrated adenoma which caused overt bleeding.2035_A Figure 1. Endoscopic findings. (a): A lobulating pedunculated polyp was noted in capsule endoscopy; (b, c): A 2.5cm sized polyp with long stalk and bleeding was found at duodenojejunal junction; (d): A 1.8cm sizxed lobular enhancing nodule at duodenojejunal junction.2035_B Figure 2. Images of the polypectomy. (a): A detachable snare was used for the prevention of bleeding during polypectomy (B) The polyp was removed without complication (c) The resected specimen of duodenal polyp2035_C Figure 3. Microscopic findings. Traditional serrated adenoma; (a): exophytic, tubulovillous or villous polypoid lesion; (b): deep clefts, indentations and slit-like spaces, leading to broad luminal fronds that protrude into the gland lumen or from surface of a papillary frond often in a broad flat-topped, mushroom-like or jigsaw puzzle-like appearance; (c): striking granular eosinophilic cytoplasm, luminal serrations, presence of elongated, penicillate nuclei with evenly dispersed coarse chromatin and small inconspicuous nucleoli