Rare Orbital Metastasis Originating from Ampullary Adenocarcinoma

Background: Orbital metastasis from ampullary carcinoma is rare, with no previously reported cases. Case presentation: We report the case of a 60-year-old man who complained of a right-sided headache, blurred vision, progressive proptosis, ptosis, and right eye pain for 3 months. His past medical history included an ampullary adenocarcinoma stage IIIA treated via the Whipple procedure and adjuvant chemoradiotherapy 1 year ago. However, he was lost to follow-up. Computed tomography of the orbit showed a soft tissue lesion in the right orbital fossa measuring 3.3 x 2 x 2 cm. An orbital mass biopsy demonstrated an intestinal-type adenocarcinoma that tested positive for cytokeratins 7 and 20 and CDX2 on immunohistochemical staining. The pathologic diagnosis was metastatic adenocarcinoma from the ampulla of Vater. Despite oncological treatment, the patient's illness progressed. He received palliative treatment and died 1 month later. Conclusions: We presented a rare case of orbital metastasis from ampullary adenocarcinoma. This should be considered in the differential diagnosis of patients with a history of ampullary adenocarcinoma who present with symptoms referring to the relevant locations.