Atypical Retinal Pigment Epithelial Hyperplasia and Glial Proliferation Masquerading as Progressive Recurrent Retinoblastoma: A Case Report Review and Clinicopathologic Correlation

Abstract

Background: Recurrences of retinoblastoma tumors, particularly scar recurrences, are a common phenomenon in the management of this cancer. Consolidative treatment with laser and cryotherapy are required for local control of disease. It is known that consolidative therapy can induce retinal pigment epithelium (RPE) hyperplasia and gliosis. Herein we report extensive RPE hyperplasia and gliosis during laser therapy for a focal scar recurrence, which presented as a progressive retinal opacification mimicking active retinoblastoma. Method: This is a retrospective case review. Results: A 2-month-old premature male was diagnosed with sporadic bilateral retinoblastoma (International Intraocular Retinoblastoma Classification [IIRC] group B in the right eye and IIRC group A in the left eye). The patient underwent laser therapy for a focal recurrence which demonstrated a white lesion during therapy and was subsequently enucleated. While there was a focal recurrence and infiltration of the retina (seen both on optical coherence tomography and histopathologic section), the majority of the white, progressive lesion was from extensive RPE hyperplasia and gliosis secondary to laser therapy. Conclusion: Clinicopathologic correlation of the active recurrence and adjacent gliosis is demonstrated.

Retinal pigment epithelium exhibits cell size, gene expression, and phagocytic activity alterations when exposed to retinoblastoma chemotherapeutics

“…RPE alterations and other adverse events, including RPE hyperplasia, gliosis, and mottling, have been previously documented in the eyes of some Rb patients treated with Melphalan and Topotecan [7,9,14]. [14] were the rst to report cytotoxicity of Melphalan, Topotecan, and carboplatin on RPE cells.…”

“…The retinal pigment epithelium (RPE) is a pigmented cell monolayer responsible for transporting metabolic end products from the subretinal space to the blood and recycling photoreceptor outer disks for the maintenance of visual cells [6]. RPE hyperplasia, gliosis, mottling, and other alterations on ultimate visual acuity can manifest following chemotherapy in Rb patients [7][8][9]. As the RPE is vital for the health and function of the neural retina, any failure of any RPE functions can lead to retinal degeneration, loss of visual function, and blindness [10].…”

Progressive Preretinal Fibrosis with Late, Ossifying, Proliferative Retinopathy following Treatment for Retinoblastoma

“…Aziz et al [11] recently reported 2 cases of hemorrhagic retinopathy, though these occurred only 1 week after a second intravitreal melphalan injection. Systemic chemotherapy with laser consolidation has also been reported to result in glial proliferation [12]. In this case, our patient was treated with all of the above therapies: systemic chemotherapy with laser consolidation, salvage IAC, and intravitreal melphalan.…”

“…temic chemotherapy with laser consolidation has also been reported to result in glial proliferation [12]. In this case, our patient was treated with all of the above therapies: systemic chemotherapy with laser consolidation, salvage IAC, and intravitreal melphalan.…”