Octreotide Scintigraphy for the Detection of Paragangliomas

Abstract

Paragangliomas are neuroendocrine tumors located primarily in the head and neck region, but they can also occur at other sites. Confirming the preoperative diagnosis and detecting synchronous tumors may be difficult in some patients. Octreotide is a somatostatin analog that, when coupled to a radioisotope, produces a scintigraphic image of tumors expressing somatostatin type 2 receptors. Paragangliomas, like many neuroendocrine tumors, have been found to have a high density of somatostatin type 2 receptors on the cell surface. This study compared the results of preoperative octreotide scintigraphy with the histopathology in 21 patients who underwent surgery for presumed head and neck paragangliomas. Octreotide scan findings were positive in 16 patients with paragangliomas and negative in 3 patients with other pathology. One false-positive and 1 false-negative result were obtained. Thus, this test had an accuracy of 90%, a sensitivity of 94%, and a specificity of 75%. Previously unidentified synchronous tumors were identified in 5 patients. On the basis of this series of patients, octreotide scintigraphy appears to be a reliable test to detect paragangliomas and may be quite helpful in preoperative planning.