Woman With Weight Loss and Abdominal Pain and Fullness

A 35-year-old woman has been losing weight and has hadworsening abdominal pain and fullness for the past 2 months.She denies nausea, vomiting, and fever. Medical history issignificant only for asthma.

This thin woman is in no distress. Temperature is37.1^oC (98.8^oF); heart rate, 82 beats per minute; respirationrate, 14 breaths per minute; and blood pressure,126/80 mm Hg. Heart and lungs are normal. Bowelsounds are normal, and liver and spleen are both normalsize. Palpation of the abdomen suggests the presence of alesion in the midline: the area is mildly tender, althoughthere is no guarding.

Because of this finding and the patient's weight loss,you order a CT scan of the abdomen. The axial image fromthis scan reveals a soft tissue density just anterior to the commoniliac artery on the right, at the level of the iliac crest(Figure 1). It is located within the mesentery and displacesadjacent bowel.

To obtain more detailed information, you order anMRI scan. On T1-weighted images, the lesion is isointensewith muscle (Figure 2); on T2-weighted images, it demonstratesincreased signal (Figure 3). The lesion displacessmall bowel, as was shown on CT. The MRI findings arenonspecific but are consistent with a mass.

A fine-needle biopsy of the lesion is performed, and carcinoidis diagnosed.

Which nuclear medicine test will you order to confirmthe diagnosis and determine the extent of the disease?

WHICH TEST-AND WHY:Octreotide scintigraphy is themost sensitive examination for carcinoid tumors; its sensitivityis more than 90%-greater even than that of CT.Octreotide scintigraphy is also useful as an adjunct toanatomic imaging in the identification of pancreatic endocrinetumors, especially insulinomas, gastrinomas, glucagonomas,and somatostatinomas.

In addition, because an octreotide scintigram is atotal body scan, it makes a cost-effective total body analysispossible. The extent of the disease dramaticallyalters management of carcinoid tumors and pancreaticendocrine neoplasms. If these tumors present with clinicalsymptoms, they often have already metastasized.

What the octreotide scintigram shows. In thispatient, the octreotide scintigram revealed a very intensefocal area of increased activity in the midline (Figure4). This correlated with the abnormality identifiedon CT and MRI and was consistent with a diagnosis ofprimary carcinoid tumor. Single-photon emission CT(not shown) confirmed that the lesion was in the anterioraspect of the mesentery. No other focal lesions wereidentified.

Outcome of this case. The tumor was surgically resected.Three months later, the patient had no symptoms.