111 Indium Pentetreotide Imaging in the Evaluation of Head and Neck Tumors

Objectives/Hypothesis: Peptide receptor imaging with 111 Indium pentetreotide is useful in the diagnosis of diffuse neuroendocrine system tumors (DNEST) of the head and neck. Uses of 111 Indium pentetreotide scintigraphy include tumor and metastases detection, familial tumor screening, and surveillance for recurrence. Using target to background ratios (TBR) could generate a comparative scale for these tumors. Study Design: A retrospective study evaluated the size, TBR, conventional imaging, and outcomes of patients imaged with 111 Indium pentetreotide scintigraphy for suspected head and neck DNEST. Methods: Patients with head and neck tumors imaged by 111 Indium pentetreotide scintigraphy during a nine‐year period were reviewed. Data analyzed were age, sex, scintigraphy, pathology, and conventional radiology. Tumor data included dimension, multiplicity, metastases, and tumor and brain counts. Results: Fifty‐three patients underwent 58 scans. The sensitivity and specificity were 93% and 92%. Several different DNEST were successfully evaluated, including familial paragangliomas and multiple paragangliomas. TBRs were variable depending on type of DNEST. Conclusions: 111 Indium pentetreotide scintigraphy is accurate in determining the presence of paragangliomas, carcinoid tumors, esthesioneuroblastomas, small cell neuroendocrine tumors, andmetastases. It is an excellent surveillance tool. Screening patients for familial paragangliomas can be accomplished. No reliable comparative scale to distinguish amongst the various DNEST could be developed using TBR.