Somatostatin Receptor-PET/CT/MRI of Head and Neck Neuroendocrine Tumors

• Published in: American journal of neuroradiology : AJNR Vol. 44; no. 8; pp. 959 - 966
• Main Authors: Rini, J N, Keir, G, Caravella, C, Goenka, A, Franceschi, A M
• Format: Journal Article
• Language: English
• Published: United States American Society of Neuroradiology 01.08.2023
• Subjects: Head & Neck; Humans; Magnetic Resonance Imaging - methods; Meningeal Neoplasms; Nasal Cavity - pathology; Neuroendocrine Tumors - diagnostic imaging; Neuroendocrine Tumors - pathology; Nose Neoplasms; Organometallic Compounds; Positron Emission Tomography Computed Tomography - methods; Positron-Emission Tomography - methods; Receptors, Somatostatin
• ISSN: 0195-6108; 1936-959X; 1936-959X
• DOI: 10.3174/ajnr.A7934

Due to its high sensitivity, somatostatin receptor-PET may detect smaller lesions and more extensive disease than contrast-enhanced MR imaging, while the superior spatial resolution of MR imaging enables lesions to be accurately localized. We compared results of somatostatin receptor-PET/MRI with those of MR imaging alone and assessed the added value of vertex-to-thigh imaging for head and neck neuroendocrine tumors. Somatostatin receptor-PET/CT was acquired as limited brain or head and neck imaging, with optional vertex-to-thigh imaging, following administration of CU/ GA DOTATATE. Somatostatin receptor-PET was fused with separately acquired contrast-enhanced MR imaging. DOTATATE activity was classified as comparable, more extensive, and/or showing additional lesions compared with MR imaging. Vertex-to-thigh findings were classified as positive or negative for metastatic disease or incidental. Thirty patients (with 13 meningiomas, 11 paragangliomas, 1 metastatic papillary thyroid carcinoma, 1 middle ear neuroendocrine adenoma, 1 external auditory canal mass, 1 pituitary carcinoma, 1 olfactory neuroblastoma, 1 orbital mass) were imaged. Five had no evidence of somatostatin receptor-positive lesions and were excluded. In 11/25, somatostatin receptor-PET/MRI and MR imaging were comparable. In 7/25, somatostatin receptor-PET/MRI showed more extensive disease, while in 9/25, somatostatin receptor-PET/MRI identified additional lesions. On vertex-to-thigh imaging, 1 of 17 patients was positive for metastatic disease, 8 of 17 were negative, and 8 of 17 demonstrated incidental findings. Somatostatin receptor-PET detected additional lesions and more extensive disease than contrast-enhanced MR imaging alone, while vertex-to-thigh imaging showed a low incidence of metastatic disease. Somatostatin receptor-PET/MRI enabled superior anatomic delineation of tumor burden, while any discrepancies were readily addressed. Somatostatin receptor-PET/MRI has the potential to play an important role in presurgical and radiation therapy planning of head and neck neuroendocrine tumors.