title: Radiosensitive orbital metastasis as presentation of occult colonic adenocarcinoma.
abstract: An 82-year-old man presented with progressive right frontal headaches. The patient's history was significant for benign polyps on surveillance colonoscopy 2 years prior, without high-grade dysplasia or carcinoma. MRI revealed an enhancing lesion arising within the superomedial aspect of the right orbit. Lesion biopsy demonstrated histological appearance and immunophenotype suggestive of colonic adenocarcinoma. Staging positron emission tomography/CT showed visceral metastases and diffuse activity in the posterior rectosigmoid, consistent with metastatic colon cancer. Treatment of the orbital lesion with external beam radiotherapy to 30 Gy resulted in significant palliation of the patient's headaches. The patient expired 2 months following treatment completion due to disease progression. Orbital metastasis as the initial presentation of an occult colorectal primary lesion is exceedingly rare, and occurred in this patient despite surveillance colonoscopy. Radiotherapy remains an efficacious modality for treatment of orbital metastases.
authors.affiliation: Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Ethan B
authors.initials: EB
authors.lastname: Ludmir
authors.affiliation: Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Shannon J
authors.initials: SJ
authors.lastname: McCall
authors.affiliation: Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Brian G
authors.initials: BG
authors.lastname: Czito
authors.affiliation: Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Manisha
authors.initials: M
authors.lastname: Palta
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000473:pathology*; D003111:Colonic Polyps; D003113:Colonoscopy; D017809:Fatal Outcome; D006801:Humans; D008297:Male; D009918:Orbital Neoplasms / Q000556:secondary*; D049268:Positron-Emission Tomography