Retinoblastoma with MYCN Amplification Diagnosed from Cell-Free DNA in the Aqueous Humor

Sarah Joseph; Sarah Pike; Chen-Ching Peng; Brianne Brown; Liya Xu; Jesse L Berry; Patricia Chévez-Barrios; G Baker Hubbard; Hans E Grossniklaus

doi:10.1159/000533311

Retinoblastoma with MYCN Amplification Diagnosed from Cell-Free DNA in the Aqueous Humor

Ocul Oncol Pathol. 2024 Apr;10(1):15-24. doi: 10.1159/000533311. Epub 2023 Aug 25.

Authors

Sarah Joseph¹, Sarah Pike², Chen-Ching Peng^{2

3}, Brianne Brown², Liya Xu^{2

3}, Jesse L Berry^{2

3

4}, Patricia Chévez-Barrios⁵, G Baker Hubbard¹, Hans E Grossniklaus^{1

6}

Affiliations

¹ Department of Ophthalmology, Emory University School of Medicine, Los Angeles, CA, USA.
² Children's Hospital Los Angeles and the USC Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
³ The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA.
⁴ Norris Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
⁵ Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, USA.
⁶ Department of Pathology, Emory University School of Medicine, Los Angeles, CA, USA.

Abstract

Introduction: The objective of this study was to report the clinicopathologic features of three cases of MYCN-amplified retinoblastoma identified genetically by aqueous humor sampling.

Methods: Whole-genome sequencing was performed using isolated cell-free DNA (cfDNA) from aqueous humor of 3 retinoblastoma patients. We analyzed genomic copy number and mutational alterations, histologic and pathologic features, and clinical data.

Results: The most common genetic alteration identified in these three retinoblastoma cases was a focal MYCN amplification on 2p. All tumors showed an early age of diagnosis with a median of 9 months. The tumor histopathologic features included neovascularization and subretinal seeding in case 1, diffuse nature with choroidal and prelaminar optic nerve invasion in case 2, and complete vitreous seeding in case 3. Case 1 expressed RB protein and had no RB1 mutation, case 2 did not express RB protein and had an RB1 mutation, and case 3 did not express RB protein and likely had an epigenetic effect on RB expression.

Conclusions: Our report shows 3 cases of unilateral retinoblastomas diagnosed in patients ranging from 4 months to 18 months old. Genomic analysis from AH cfDNA revealed MYCN amplification with intact RB protein staining in case 1 and lack of RB staining in cases 2 and 3. RB1 mutational analysis in the AH confirmed a pathogenic variant in case 2. Clinical pathology showed features requiring aggressive treatment, specifically enucleation.

Importance: MYCN-amplified retinoblastomas demonstrate unique pathogenesis and aggressive behavior, regardless if MYCN is a primary or secondary driver of disease. Genomic analysis from aqueous humor may be useful when deciding to enucleate as opposed to treating conservatively. Focal MYCN amplification on 2p might be relevant for tumor growth in this subset of the retinoblastoma population in terms of targeted therapeutics.

Keywords: Aqueous humor; Leukocoria; Oncogene; Retinoblastoma; Vitreous.

Publication types

Case Reports

Grants and funding

This study was funded by NIH P30EY06360 (HEG), an unrestricted departmental grant from Research to Prevent Blindness (H.E.G), NIH K08CA232344 (J.L.B.), the Wright Foundation (J.L.B.), Children’s Oncology Group/St. Baldrick’s Foundation (J.L.B.), Danhakl Family Foundation (J.L.B.), the Knights Templar Eye Foundation (J.L.B., L.X.), Hyundai Hope on Wheels (J.L.B.), A. Linn Murphree, Chair in Ocular Oncology (J.L.B.), the Berle & Lucy Adams Chair in Cancer Research (J.L.B.), the Larry and Celia Moh Foundation (J.L.B.), an unrestricted departmental grant from Research to Prevent Blindness (J.L.B., L.X.).