Acute Bleeding In Duodenal Gastrointestinal Stromal Tumor
A 24-year-old male had no history of previous medical problem , but complained of acute upper gastrointestinal bleeding (hematemesis). A submucosal tumor located about 3 cm distal to the papilla of Vater was found by endoscopy. The lesion bulged beneath the mucosa with a central depressed ulceration, which was the origin of the massive bleeding. Following blood transfusion the bleeding spontaneously stopped ().\nMagnetic resonance imaging (MRI) was remarkable for a homogenous tumor of the duodenum (). MRI and CT scans showed no metastases. The patient experienced another episode of bleeding for which a blood transfusion was performed due to a decreased hemoglobin level to 4g/dl. Fortunately the bleeding stopped again. Endoscopic ultrasonography showed a 12 x 10mm hypoechoic lesion that originated from the muscularis layer without any regional lymphadenopathy. The patient was diagnosed to have a duodenal GIST ( ).Surgery was recommended and a laparotomy was done. The submucosal tumor was located in the distal third portion of the duodenum, about 3 cm distal to the ampulla of Vater. No penetration of the pancreas or other adjacent organs was detected and there were no suspicious lymph nodes. The tumor was managed by a partial resection of the distal third and fourth portion of the duodenum with a 1cm safe margin on each side and an end-to-end anastomosis. His postoperative course passed without any problem and the patient was discharged on the fifth day after the operation. The diameter of the operated tumor was 3 cm (). Histopathology showed a GIST with a typical spindle tumor cell structure (). The overlying duodenal mucosa was ulcerated. The tumor had a thin fibrous capsule that reached the muscularis mucosae, but did not penetrate it. The tumor had a moderately malignant potential according to tumor grading and the excised margin was tumor-free. Immunohistochemistry was strongly positive for C- KIT and CD34 and DOG-1 and KI67(the pathologic tumor mitotic labeling index which expression has positive correlation to tumor size) =8% , while desmin, smooth muscle, HH8, EMA and beta-catenin were negative. Mitotic activity was less than 5 mitoses/10 high power fields (). No formal lymph node dissection was done, and as it was expected no lymph nodes were noticed in the resected specimen. The tumor diameter and low proliferative activity revealed a low risk for malignancy.