Bleeding Gastrointestinal Stromal Tumor of the Jejunum Detected by a Tc-99m Red Blood Cell Gastrointestinal Bleeding Scan

A predominant pelvic gastrointestinal stromal tumor (GIST) mass observed on Tc-99m red blood cell gastrointestinal bleeding scintigraphy

A 51-year-old woman presented with recurrent bleeding per rectum. Her earlier endoscopies were negative. Tc-99m RBC GI bleeding scintigraphy was performed. It demonstrated an apparent hypervascular pelvic mass, and active small bowel bleeding. Based on scintigraphic finding of a predominant pelvic mass indicating tumor, CT of the abdomen and pelvis was performed for further gastrointestinal bleeding localization work up instead of an invasive angiography or endoscopy, which detected a small bowel tumor in the pelvis. A small bowel gastrointestinal stromal tumor was resected subsequently.

Diffuse peritoneal metastases from primary colon cancer demonstrated by Tc-99m-labeled red blood cell scintigraphy

An 80-year-old man, who underwent complex abdominal surgery for left colon cancer 2 years earlier, was hospitalized because of severe anemia and recurrent episodes of melena. Esophagogastroduodenoscopy and colonoscopy did not reveal abnormal findings. Abdominal ultrasonographic examination and computed tomographic scan failed to detect tumor recurrence or metastatic lesions but moderate ascites was found. Tumoral marker serum levels were abnormal. Tc-99m red blood cell scintigraphy was performed and disclosed a potential site of intestinal hemorrhage: both dynamic and static images showed a slight but diffuse and persistent uptake of Tc-99m erythrocytes in the entire abdomen with no clear evidence of a site of active bleeding. These findings suggested diffuse peritoneal micrometastases, which were confirmed at autopsy.

F-18 FDG PET imaging in gastrointestinal stromal tumor

Gastrointestinal stromal tumor (GIST) is the most frequent mesenchymal malignancy of the gastrointestinal tract. Liver and peritoneum are the most frequent metastatic sites. Surgery is the mainstay of treatment in patients with localized disease. Imatinib mesylate (Gleevec; Novartis Pharmaceuticals, East Hanover, NJ), an inhibitor of tyrosine kinase activity of KIT receptor, has been shown to be an effective treatment in metastatic or unresectable disease. Follow-up of patients treated with Gleevec is controversial. The authors present a case of GIST that showed near-total response with Gleevec on fluorodeoxyglucose positron emission tomography. They suggest positron emission tomography as a useful imaging modality for the monitoring of therapy response in GIST tumors treated with Gleevec.

Abdominal wall hematomata and colonic tumor detected on labeled red blood cell scintigraphy: case report

Gastrointestinal (GI) bleeding is not uncommon and responsible for considerable morbidity and mortality. Radionuclide red blood cell scintigraphy (RBCS) is a well established imaging modality for identifying patients with ongoing active GI bleeding. However, false positive RBCS are known to occur. The authors report the findings of a RBCS in an elderly female, who developed GI bleeding following the commencement of anticoagulant therapy. Although active GI bleeding was not identified, two abdominal wall hematomata and a cecal adenocarcinoma were detected. Distinguishing features of these lesions are described.