A Case Report of an Unusual Presentation of a Pedunculated Gastrointestinal Stromal Tumor: Acute Upper Gastrointestinal Bleeding in a 57-Year-Old Female.

Gastrointestinal stromal tumors (GISTs) are rare tumors accounting for 0.1-3% of gastrointestinal (GI) neoplasms. ‏In the past, GIST was classified as leiomyomas, leiomyosarcomas, and leiomyoblastomas. However, now it is evident that GIST is a separate tumor entity, and it is the most frequent sarcoma of the GI tract. We report a case of a 57-year-old female with a five-day history of black tarry stools, two episodes of vomiting of dark-colored blood, dizziness, abdominal pain, night sweats, and palpitation, provoked by a change of position. After a computerized tomography (CT) of the abdomen and pelvis, a GIST was suspected, which was confirmed with histopathology. Acute upper GI bleeding is a rare presentation of GIST. Clear guidelines should be developed for GIST. An early diagnosis is crucial for a better prognosis.