Unusual Clinical Behavior of a Very Late Retinoblastoma Relapse in a Patient with a Germline RB Mutation

Abstract

Retinoblastoma is the most common ocular tumor of childhood with cure rates exceeding 95%. Patients with high-risk features typically relapse within 3 years of diagnosis. We report a patient with low-risk bilateral retinoblastoma who suffered systemic relapse after eight years. His disease at first relapse was chemosensitive without PET avidity or bone marrow disease following therapy. Six months later, he experienced an isolated CNS relapse and succumbed to refractory disease. “Oncoseq” exome sequencing confirmed the presence of germline RB mutation among all tissues as well as somatic changes which may provide insights into the biology of relapse and tumor.