Albert Shu-Sen Chang MD, Presenter: Nothing to Disclose

Ari Plosker, Abstract Co-Author: Nothing to Disclose

Guiyun Wu, Abstract Co-Author: Nothing to Disclose

Narendra Nathoo MD, Abstract Co-Author: Nothing to Disclose

Michael Vogelbaum MD, Abstract Co-Author: Nothing to Disclose

Jeffrey S. Ross MD, Abstract Co-Author: Nothing to Disclose

Gene Barnett MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Precise diagnosis of dural based lesions is often problematic. The purpose of this study is to retrospectively review the utility of In-111 Octreotide SPECT versus MRI/CT imaging in the diagnosis of intracranial lesions suspected to be meningiomas.

Brain In-111 Octreotide SPECT studies performed between January 1998 and December 2002 were retrospectively reviewed. SPECT findings were correlated with available PET, MRI, CT, histopathologic information and clinical follow-ups.

Sixty-five patients underwent In-111 Octreotide SPECT studies for 80 intracranial lesions, which all have MRI/CT correlation. Forty-eight additionally have FDG-PET correlation. Seventeen intracranial lesions had available histopathologic information, of which 6 were meningioma, and the others comprised lymphoma (4), prolactinoma, hematoma, fibrous dysplasia, metastases (2), sarcoma and abscess. Among the 6 histopathologically identified meningiomas (of which one was a collision tumor of renal cell carcinoma metastasis into a meningioma), 5 out of 6 presented with concordant octreotide findings, 4 out of 5 concordant PET findings as well as 6 out of 6 concordant MR/CT findings. Among the 11 non-meningioma lesions, 8 presented with concordant octreotide findings, 3 out of 7 concordant PET findings as well as 4 out of 11 concordant MR/CT findings. In identifying meningioma, octreotide SPECT study had 83% sensitivity (Sens), 27% specificity (Spec), 39% positive predictive value (PPV) and 75% negative predictive value (NPV). PET imaging had 80% Sens, 57% Spec, 57% PPV, 80% NPV. MRI/CT had 100% SENS, 64% SPEC, 60% PPV, 100% NPV. Subset of remaining lesions without histopathologic information were diagnosed as meningiomas largely by concordant octreotide/MRI/CT findings as well as clinical and imaging stability during serial follow-ups.

In-111 Octreotide SPECT is a highly sensitive but nonspecific diagnostic indicator of meningioma, with high negative predictive value among the patient population at our institution. Available histopathologic information indicated positive octreotide findings can misrepresent intracranial lesions of diverse etiologies (e.g. metastases, lymphoma) as meningioma.

Chang, A, Plosker, A, Wu, G, Nathoo, N, Vogelbaum, M, Ross, J, Barnett, G, et al, , Indium-111 Octreotide SPECT versus MRI for Diagnosis of Intracranial Lesions.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4405250.html