Unusually very late-onset new growth of intraocular retinoblastoma: A case report and review of literature

PURPOSE: To report a patient who presented with a very late-onset new growth of intraocular retinoblastoma, which occurred 11 years after the initial combined treatment. OBSERVATIONS: A 12-year-old monoophthalmic female patient presented with bilateral familial retinoblastoma showing new growth of intraocular tumor after 11 years of complete regression following combined local and systemic treatments. The new tumor growth was treated with diode laser transpupillary thermotherapy, ruthenium-106 plaque radiotherapy and adjuvant intravenous chemotherapy and the tumor regressed. CONCLUSIONS AND IMPORTANCE: Despite initial satisfactory treatment and complete regression of the tumor, very late-onset new growth of intraocular retinoblastoma can occur. Hence, life-long follow-up in all patients with retinoblastoma is warranted, given the risk for new tumor formation even later in life. To our knowledge, this is the first report of new growth of intraocular retinoblastoma after regression for more than a decade.