Patient 1 is a 72-year-old female who was initially diagnosed in 1997 with a well differentiated G3 (Ki-67 20%) metastatic jejunal NET. Her primary tumor was resected after diagnosis and a liver transplant was performed in 1998 for bulky symptomatic liver metastases. She has received a series of therapies including octreotide, lanreotide, and everolimus for her carcinoid syndrome (CS) and disease control. In May 2017, a 68Ga-DOTATATE PET-CT revealed somatostatin receptor (SSTR) avidity in bilateral orbits although she was asymptomatic from a visual symptom standpoint (Fig. a and b). In March 2018, the patient was hospitalized for preseptal cellulitis. During the hospitalization, she underwent a CT scan which revealed focal thickening of the right medial rectus and left lateral rectus muscles. Opthalmology evaluated her and felt the cellulitis was unrelated to her orbital masses. Once her infection resolved she underwent biopsy of a rectus muscles mass which confirmed orbital metastases from her NET primary. Patient did not have any worsening visual symptoms or signs (limited extraocular motility, visual field deficits or proptosis).\n177Lu-DOTATATE PRRT was initially recommended; however, this was not pursued due to the patient’s poor renal function. Radiation therapy was then considered but given the proximity of the lesions to other critical structures and her lack of symptoms, this too was deferred in favor of close surveillance. In July 2018, she started on capecitabine and temozolomide for better systemic control of her NET, which also involved her liver, pancreas, bone and intra-abdominal lymph nodes. On a follow-up orbital MRI in July 2018, her lesions were noted to be stable.
A 62-year-old man had a neuroendocrine tumor of the rectum treated by colon resection and radiation therapy. Three years later, he experienced diplopia and right periorbital swelling and also was found to have metastasis to the liver, lung, and groin. Indium-111 OctreoScan demonstrated a mass in the right orbit. Visual acuity was no light perception in the right eye (OD) and 20/30 in the left eye (OS). There was right eye proptosis of 10 mm on exophthalmometry and decreased ocular motility in all gazes. Magnetic resonance imaging (MRI) of the orbits revealed a 30-mm well-circumscribed intraconal mass adjacent to the medial rectus muscle displacing the optic nerve medially. The lesion was isointense on T1-weighted images with moderate enhancement after contrast. Enucleation and anterior orbitotomy were performed for the painful blind eye and tumor resection, respectively. Histopathology of the resected lesion showed metastatic neuroendocrine tumor with the tumor cells staining positive for chromogranin, synaptophysin, and neuron specific enolase. At 2 years follow-up, there was no orbital recurrence of the tumor; however, there was progression of the liver, lung, and skin metastases. Despite chemotherapy (carboplatin and TP-16) and external beam radiotherapy (EBRT) of extraorbital tumors, the patient died 3 years after orbital surgery.