Optic Nerve Obscuration in Retinoblastoma: a Risk Factor for Optic Nerve Invasion?

Abstract

Purpose : Obscuration of the optic nerve is a common finding in advanced intraocular retinoblastoma, but there are no previous studies examining its risk for optic nerve invasion. The objective of this study is to evaluate the risk of optic nerve invasion associated with optic nerve obscuration either at diagnosis or that persists during treatment. In addition, a case series of 4 patients with advanced retinoblastoma and complete obscuration of the optic nerve by tumor that persisted throughout treatment is presented.

Methods : Retrospective review from 2011-2016 of patients at Children’s Hospital Los Angeles with advanced retinoblastoma (Group D/E) with complete obscuration of the optic nerve at diagnosis and a second group of patients who had persistent obscuration through the course of therapy. RetCam fundus photographs from examination under anesthesia (EUA) at diagnosis, and each subsequent EUA, were evaluated for completed obscuration of the optic nerve by the tumor.

Results : Advanced retinoblastoma was diagnosed in 102 eyes of 86 patients. The optic nerve was obscured in 69 eyes (68%) at diagnosis. Of these, 30 (43%) underwent salvage therapy and 39 (57%) primary enucleation. Histopathologic analysis of primarily enucleated eyes with optic nerve obscuration showed 41% pre-laminar invasion and 15% post-laminar invasion. Four eyes in the salvage group had persistent nerve obscuration throughout treatment; 2 were subsequently enucleated without evidence of optic nerve invasion. Average follow up was 23.5 months (range 1-62 months).

Conclusions : Optic nerve obscuration at diagnosis may be associated with higher-risk pathologic features including post-laminar optic nerve invasion. While persistent post-treatment obscuration of the optic nerve by retinoblastoma is a relatively poor prognostic sign for both globe salvage and vision, it does not appear, in this small cohort, to increase the risk of optic nerve invasion during or after treatment. With appropriate control of the intraocular tumor, these eyes can be safely salvaged.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.

 

Consort Diagram showing Clinical and Pathologic features of Advanced Retinoblastoma Eyes with and without Obscuration of the Optic Nerve at Diagnosis.

 

Fundus Photos of Four patients with Advanced Retinoblastoma with Persistent Obscuration of the Optic Nerve through the course of therapy. Patient 2 and 3 were enucleated; Patient 1 and 4 were salvaged with full control of the intraocular disease.