Choroidal Metastatasis From a Neuroendocrine Tumor Masquerading as Choroidal Melanoma

A mushroom-shaped choroidal mass is classically suggestive of melanoma, due to the ability of these tumors to erupt through Bruch's membrane. In contrast, choroidal metastases rarely adopt this growth pattern. The authors present an unusual case of a patient with a large choroidal metastasis from a pancreatic neuroendocrine tumor that shows a collar-button configuration. The diagnosis was confirmed by histology and immunohistochemistry following enucleation. The authors review the typical appearance of choroidal metastases from neuroendocrine tumors and discuss mechanisms by which uveal tumors may extend through Bruch's membrane.