1. Introduction
Gastrointestinal stromal tumors (GIST) are specific mesenchymal tumors of the digestive tract. They were described first by Mazor and Clark (1983) [1] . They originate from the interstitial cells of Cajal [2] . Its most common site is the stomach (50% - 60%) [3] and small intestine (25% - 30%), and extremely rare in the esophagus, colon, rectum and appendix [4] . There are additional locations at digestive gallbladder, pancreas, liver and bladder. It is usually an incidental finding on imaging for the study of other diseases.
2. Case Report
A 77-year-old male came to the emergency with epigastric pain radiating to the left upper quadrant of abdomen accompanied with fever and chills without nausea or vomiting.
His medical history includes Sd Bechet, Herpes Zoster, pneumonia, prostate adenoma and vena cava thrombosis.
Abdominal examination revealed the presence of abdominal pain and distension without evidence of peritonitis. In blood test was observed the presence of leukocytosis.
Abdominal ultrasound and CT showed retrogastric collection of 15 cm (Figure 1). Emergency atypical gastric

Figure 1. Perforated GIST with retrogastric collection.
resection was performed because of a perforated gastric tumor with peritoneal implants and splenic hilum extension. Histopathology revealed a gastric GIST. In subsequent tests no disease recurrence was observed. The treatment was completed with adjuvant therapy with Imatimib.
3. Discussion
Gastrointestinal stromal tumors are extremely rare. The perforation is an exceptional presentation.
The clinical features are variable and depend on the size and location of the tumor. The most common signs and symptoms are mass effect and bleeding accompanied by abdominal discomfort and rarely with complications [5] [6] . Perforation is extremely rare. There are 16 cases in medical literature of GIST tumors with this debut, all in jejunum [7] , including a jejunal diverticulum [8] . No documented cases of gastric perforation until today, but there is an esophageal perforation [9] .
Surgery is the only potentially curative treatment. It should be made a R0 resection with clear margins of 1 - 2 cm preventing rupture of the tumor [10] [11] . Lymphadenectomy is not required.
Treatment with inhibitors of tyrosine kinase receptor (imatinib) marked a big change in the prognosis of GIST tumors has led to increased survival rates. The age of presentation, anatomic location, size and histology are the most important prognostic factors [5] [11] .
4. Conclusion
The diagnosis of perforated gastric GIST tumor should be considered in emergency surgery as a differential diagnosis even when it is a rare entity in clinical practice.