Choroidal melanoma overlying scleral buckle evading detection treated with proton beam radiotherapy

Abstract

Purpose: to present a case of a choroidal melanoma located along a scleral buckle contour and was successfully treated with proton beam radiotherapy, without disturbing the scleral buckle. Observations: A 60-year-old woman presented with photopsias and history of retinal detachment repair with scleral buckle 36 years prior. She had annual dilated exams with her ophthalmologist over the last several years. While initially diagnosis of choroidal detachment, hemorrhage and intraocular buckle intrusion were suspected, the patient was referred to an ophthalmic oncology center and choroidal melanoma was confirmed. The patient underwent tantalum marker placement, trans-retinal biopsy and proton beam radiotherapy. Despite no evidence of metastatic disease on systemic imaging, prognostic genetic testing of the tumor revealed high-risk alterations for future metastasis, and the patient enrolled in an adjuvant clinical trial. Conclusions: The location of this choroidal melanoma along a scleral buckle contour presented a unique therapeutic challenge. We successfuly treated the tumor with proton beam radiotherapy without disturbing the scleral buckle. Importance: chorioretinal elevations adjacent a scleral buckle may be presumed to be due to the buckle element; ultrasound can be helpful in distinguishing an intraocular tumor. Proton beam radiotherapy has the advantage over plaque brachytherapy in this setting as removing the scleral buckle is not needed and placing a plaque over the scleral buckle risks altering the effective radiotherapy dose.

Keywords

• Choroidal melanoma
• Ocular melanoma
• Scleral buckle
• Proton beam radiotherapy
• Next-generation sequencing