Extra-Gastrointestinal Stromal Tumor Presenting as an Anterior Chest Wall Mass

A 71-year-old man was referred for an anterior chest wall mass. Chest computed tomography (CT) and positron emission tomography-CT suggested a malignant tumor. Surgical biopsy through a vertical subxiphoid incision revealed an extra-gastrointestinal stromal tumor (EGIST). En bloc resection of the tumor, including partial resection of the sternum, costal cartilage, pericardium, diaphragm, and peritoneum, was performed. Pathologic evaluation revealed a negative resection margin and confirmed the tumor as an EGIST. On postoperative day 17, the patient was discharged without any complications. At the 2-week follow-up, the patient was doing well and was asymptomatic.

Primary Retroperitoneal Malignant Gastrointestinal Stromal Tumor Mimicking Adrenal Mass

Gastrointestinal stromal tumor (GIST) is the most common non-epithelial tumor in the gastrointestinal tract. Although GIST occurs mainly in the gastrointestinal tract, it also occurs, rarely, in non-gastrointestinal tract and in this case, it is often named as extra-gastrointestinal stromal tumor (EGIST). We experienced a 68-year-old male patient who had been diagnosed preoperatively with accidentaloma of the left adrenal gland by computed tomography, and finally diagnosed as primary retroperitoneal malignant GIST, postoperatively. The operation was performed via anterior abdominal approach, and complete surgical resection was done for a 7 cm sized retroperitoneal tumor near the left adrenal gland. Primary retroperitoneal malignant GIST was the final pathologic diagnosis and the size of the tumor was 6.5 cm and the mitotic count was 7 per high-power field. Diffuse strong positive staining for c-kit protein, CD34 and negative staining for desmin were observed in a immunohistochemistry test. We report here the unusual case of primary retroperitoneal malignant GIST mimicking adrenal mass.

Extra-Gastrointestinal stromal tumor of the pancreas with c-KIT gene mutation: Report of a case

Mesenchymal tumors of the pancreas are quite rare, accounting for less than 1% of all pancreatic tumors. Mesenchymal tumors in the gastrointestinal tract are mainly gastrointestinal stromal tumors (GISTs). GISTs are defined as KIT-positive mesenchymal spindle cells or epithelioid neoplasms originating from the interstitial cell of Cajal. GISTs occur mainly in the stomach, small intestine, colorectum and esophagus. However, extra-gastrointestinal stromal tumors in the bladder, gallbladder, omentum, and mesentery are rare. We report a case of GIST in the pancreas head. A 55-year-old female patient was referred to our hospital for a pancreas head mass detected by a CT scan checked for a fever with an unknown origin. She underwent Whipple's operation for the 5.5x4.4cm-sized mass located in the pancreas head. A microscopic examination revealed GIST showing positive c-KIT protein expression with <5/50 HPF mitosis. C-KIT gene analysis revealed a mutation in exon 9. To the best of our knowledge, this is the first case of extra-gastrointestinal stromal tumor of the pancreas demonstrated by histology, immunohistochemistry and genetic analysis in Korea.