Metastatic small cell neuroendocrine carcinoma to the orbit manifesting as total ophthalmoplegia

Purpose: To report a case of primary ureteral small cell neuroendocrine carcinoma metastasis in the left orbital wall, with a review of the literature. Case summary: A 79-year-old male visited our clinic with a 10 day history of ocular pain, ptosis, and ophthalmoplegia in the left eye. He had been diagnosed with diabetes mellitus and was being treated for prostate adenocarcinoma. The corrected visual acuity was 0.8 in the right eye and 0.5 in the left eye. An extraocular movement test showed total ophthalmoplegia, mild exophthalmos, and ptosis in the left eye. Orbital computed tomography (CT) and magnetic resonance imaging showed an irregular mass-like enhancement in the superolateral orbital wall of the left eye, suggesting infectious and inflammatory orbital disease. After antibiotic treatment, high dose systemic steroids were administered. However, there was no improvement and the orbital CT was again performed, with no changes. A surgical biopsy for differentiating orbital tumors was performed and diagnosed as a metastatic orbital small cell neuroendocrine carcinoma. Using positron emission tomography, he was later diagnosed with a metastatic orbital small cell neuroendocrine carcinoma with multiple metastases. Conclusions: When the patient has a mass-like lesion on imaging with ocular pain, ophthalmoplegia, or ptosis, a surgical biopsy should be performed to make a diagnosis and determine the optimal management.