Bilateral retinoblastoma with one eye manifesting only posterior chamber infiltration and no retinal involvement

We report the case of a 23-month-old girl with bilateral retinoblastoma that demonstrated absence of retinal lesions in one eye but had an isolated white tumor in the posterior chamber. Genetic testing confirmed a novel and de novo RB1 germline mutation in the proband that was not carried by her parents. After intravenous chemotherapy and brachytherapy to the eye with apparently disease-free retina, anatomic and functional preservation of the eye was achieved. The patient has been in remission for 18 months.