A glaucoma drainage implant functioning as a sanctuary site for vitreoretinal lymphoma

Purpose: To report an unusual case of vitreoretinal lymphoma (VRL) in which a glaucoma drainage implant (GDI) likely functioned as a sanctuary site for relapsing disease. Observations: A 54-year-old female with recently diagnosed CNS diffuse large B-cell lymphoma (DLBCL) was referred for evaluation of VRL. Ocular history at an outside center included a 4-year reported history of uveitis complicated by glaucoma and a GDI in the left eye (OS). Initial examination revealed keratic precipitates (KP), vitreous haze with clumps of white cells OS, and vitreous biopsy revealed DLBCL OS. Intravitreal methotrexate injections were initiated for primary VRL alongside systemic chemotherapy for CNS involvement with resolution of disease. One year later, the patient returned with 2+ anterior chamber (AC) and vitreous cells OS, and vitreous biopsy again revealed DLBCL OS. External radiation treatment was administered for recurrent VRL in the left eye, followed also by the right eye due to the high risk of fellow eye involvement. Autologous stem cell transplantation was then performed. Five months later, the patient returned with worsening KPs and new vitreous cells OS, and vitreous biopsy again revealed DLBCL OS. Enucleation was performed, and histopathology revealed DLBCL cells lining the GDI fibrous capsule, consistent with the GDI likely having served as a sanctuary site and source for continued local relapse. Conclusions and Importance: We report a case in which a GDI functioned as a probable sanctuary site for VRL. Sanctuary sites of malignancy should be considered in patients with pre-existing ocular hardware, particularly when recurrent relapses occur despite complete treatment.