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Plaque Radiotherapy for Medulloepithelioma in 6 Cases From a Single Center
Su Mae Ang1, Lauren A Dalvin1,2, Jacqueline Emrich3
1Ocular Oncology Service, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, PA, United States.
Purpose:
To describe outcomes of 6 patients treated with plaque radiotherapy for medulloepithelioma.
Design:
Retrospective review.
Methods:
Computerized medical records were reviewed for patients with cytopathologically confirmed medulloepithelioma and treated with plaque radiotherapy from January 1970 to December 2017. Clinical and radiotherapy parameters along with outcomes of tumor regression, globe salvage, and metastatic disease were recorded.
Results:
Of 6 patients with medulloepithelioma, plaque radiotherapy was primary (n = 5) or secondary (n = 1) treatment. The median patient age at diagnosis was 41 months (mean, 145; range, 10-624 months). Patient demographics included white race (n = 6) and female sex (n = 5). Patients presented with strabismus (n = 1), decreased vision (n = 1), ocular pain (n = 1), hyphema (n = 1), corectopia (n = 1), and visible iris lesion (n = 1). The mean tumor basal diameter was 11.2 mm (median, 10.0; range, 7.0-16.0 mm), and mean tumor thickness was 6.8 mm (median, 6.4; range, 3.1-11.0 mm). Related findings included cataract (n = 2), iris neovascularization (n = 5), secondary glaucoma (n = 2), and ectropion uveae (n = 2). The mean radiation dose to tumor apex was 44 Gy (median, 38; range, 35-70 Gy). At a mean follow-up of 59 months (range, 12-210 months), tumor control was achieved in 5 eyes (83%) with globe salvage in 4 eyes (67%). No patient had evidence of metastases or death at the last follow-up visit.
Conclusions:
Plaque radiotherapy is a reasonable alternative treatment for localized, small- to medium-size medulloepithelioma. Tumors larger than 11.0 mm, with retrolental cyclitic membrane or extrascelral extension, might still require enucleation.
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