Image Findings of a Rare Case of Neuroendocrine Tumor Metastatic to Orbital Extraocular Muscle in Gallium-68 DOTANOC Positron Emission Tomography/Computed Tomography and Therapy with Lutetium-177 DOTATATE

Metastatic tumor is one of several etiologies of space-occupying masses in the orbit that accounts for 1-13% of all orbital masses. In the adult patient population, breast cancer is the most common tumor to metastasize to the orbit, followed by metastasis from the lung, prostate, and gastrointestinal tract. Carcinoid tumors are rare neuroendocrine neoplasms derived from enterochromaffin cells, which are found primarily in the gastrointestinal tract and bronchial tree. Liver metastases are the classic presentation of distant disease. Although rare, metastatic carcinoid to the extraocular muscles (EOMs) has been relatively well described in both retrospective case reports and clinical series in the ophthalmology literature, but not in nuclear medicine. Positron emission tomography/computed tomography (PET/CT) using Ga-68-labeled somatostatin-analogues have shown superiority over other modalities for imaging of Neuroendocrine tumor We describe a case of bilateral EOM metastasis from carcinoid lung in Ga-68 DOTANOC PET/CT and treatment with Lu -177 DOTATATE.