Retinoblastoma: Symptoms, Pathology, Genetics, and Treatments

Abstract

<p>Accounting for 3% of childhood malignancies, retinoblastoma incidence varies worldwide with a higher chance of survival in developed countries typically due to earlier detection. The most common symptom of retinoblastoma is leukocoria, abnormal whitening of the retina due to the tumor formation. Childhood survival rates for retinoblastoma have increased over the past couple decades due to modifications and advances in treatments and therapies. Treatment for retinoblastoma depend on tumor size, location, malignancy, and genetics. Tumors caused by amplified MYCN proto-oncogene (also known as N-Myc proto-oncogene protein here after known as MYCN) tend to be more aggressive with diagnosis at a younger age. Bilateral retinoblastoma is typically inherited, presenting earlier than unilateral retinoblastoma but later than amplified MYCN. When not caused by only a MYCN amplification, RB1 genes predispose a patient to retinoblastoma due to disruption in the pRb pathway. Since MYCN amplification is commonly a more aggressive retinoblastoma, removal of the eye (enucleation) is a preferred treatment to prevent additional metastasis. Bilateral treatments combine various approaches such as local treatment, chemotherapy, radiotherapy, or enucleation. Unilateral cases frequently receive the same aggressive approach as bilateral retinoblastoma patients to kill the tumor before it can metastasize in the blood or along the optical nerve to the brain and cerebrospinal fluid. Certain treatments, such as external-beam radiation, can lead to a second primary malignancy in retinoblastoma survivors. A highly skilled team of ophthalmologists, pediatricians, and oncologists aim to salvage vision (if possible) while preventing retinoblastoma metastasis by customizing the treatment towards each patient.</p>