A 63-year-old man presented with diplopia, redness, and pain of his left eye of 4 weeks duration. He had a history of neuroendocrine tumor of the testicle treated by radical orchiectomy 13 years before presentation followed by metastasis to the ileum, which was treated with bowel resection. Visual acuity was 20/30 OD and 20/25 OS and exophthalmometry revealed 4 mm proptosis of the left eye with mild limitation of ocular motility in lateral gaze. An intraconal, well-circumscribed mass in the left orbit displacing the lateral rectus muscle laterally was noted on MRI []. Histopathologic evaluation following tumor excision revealed a low-grade atypical neuroendocrine tumor with positive staining for chromogranin, synaptophysin, neuron-specific enolase, and AE1/3 compatible with carcinoid metastasis. Between the next 4.5 years, the patient had three recurrences of the orbital carcinoid which were managed with EBRT, surgical excision, and eventually orbital exenteration after the MRI showed early erosion of orbital bones by the tumor and tumor extension into the maxillary bone [Figures and ]. Histopathology of the exenterated orbital lesion showed multinucleated cells with large hyperchromatic nuclei and seven mitotic figures in 10 high-power fields consistent with aggressive metastatic poorly differentiated neuroendocrine tumor. The patient also developed signs of carcinoid syndrome with carcinoid metastasis to the liver, kidney, and parotid gland. He was alive with systemic metastasis 4 years after initial presentation.\nThe clinical and pathological features as well as treatment methods and outcomes for each patient are summarized in .
A 64-year-old woman experiencing diplopia for 6 months was found to have a right orbital tumor on MRI. Three years before onset of eye symptoms, she had a colon carcinoid tumor treated by colectomy. Visual acuity was 20/20 OD and 20/40 OS. Ocular motility of the right eye was slightly limited in up and down gaze. MRI revealed a right orbital mass infiltrating the inferior rectus muscle and the resected lesion showed intermediate to large mononuclear cells with scant cytoplasm, irregular nuclei, and finely granular chromatin on histopathology, with positive staining for chromogranin, synaptophysin, pancytokeratin, and CD10, compatible with diagnosis of neuroendocrine tumor. MRI of the chest and abdomen revealed liver and lung lesions. She died 24 months after initial evaluation due to brain metastasis.