Retinoblastoma arises from the nuclear layer of the retina. The disease definition identifies an association with cytogenetic abnormalities at the 13q14 chromosomal region, which underlies the heritable predisposition in affected families. GeneReviews distinguishes between heritable retinoblastoma, in which a germline chromosomal abnormality predisposes to tumor development, and non-heritable retinoblastoma, which arises sporadically without a germline predisposition. Tumors may be multifocal, bilateral, congenital, inherited, or acquired. Individuals with bilateral or multifocal disease, or with a positive family history, are more likely to carry an underlying heritable predisposition, as noted in GeneReviews. The sporadic form accounts for approximately 60% of cases and is not associated with a heritable chromosomal change.

GeneReviews states that guidelines for the diagnosis and care of children and families affected by retinoblastoma have been published. According to GeneReviews, retinoblastoma is suspected in children presenting with leukocoria, strabismus, a change in eye appearance, or reduced visual acuity. Heritable retinoblastoma is additionally suspected in individuals with a diagnosis of retinoblastoma—including unilateral unifocal and multifocal forms—along with a positive family history. Prior to therapy planning, the extent of tumor within and outside the eye is determined. GeneReviews outlines a standard set of evaluations to establish the extent of disease following initial diagnosis. The differential diagnosis includes hereditary ocular conditions that can clinically simulate retinoblastoma: NDP-related persistent fetal vasculature, NDP-related Coats disease, tuberous sclerosis complex, Norrie disease, incontinentia pigmenti, familial exudative vitreoretinopathy, Von Hippel-Lindau syndrome, and ocular Toxocara infestation, as enumerated in GeneReviews.

Cyclophosphamide holds active FDA approval (NDA, approved July 2020) for use in retinoblastoma, as documented in the approved treatments data for this condition. Additional therapeutic approaches remain under investigation. Several agents hold FDA orphan designation for retinoblastoma—including episcleral topotecan, melphalan (two separate sponsor designations), topotecan, thioureidobutyronitrile, and a genetically modified adenovirus encoding PH20—though none of these designated agents carries current FDA approval for retinoblastoma; designation indicates investigational status, not approval. GeneReviews indicates that comprehensive guidelines for retinoblastoma care have been developed and that management planning is informed by the extent of tumor involvement within and outside the eye. Children who have undergone successful treatment require frequent follow-up examination to detect newly arising intraocular tumors, as outlined in published surveillance guidelines referenced in GeneReviews.

The clinical course of retinoblastoma depends in part on disease extent and subtype. Intraocular retinoblastoma and extraocular retinoblastoma represent distinct stages, with extraocular involvement indicating more advanced disease. GeneReviews notes that surveillance guidelines specify a framework for monitoring individuals who have had or are at risk of developing retinoblastoma, with frequent follow-up required after successful treatment to detect newly arising intraocular tumors. Individuals with the heritable form carry a documented increased risk for secondary non-ocular malignancies over the course of their lifetime, as stated in the disease definition and corroborated by GeneReviews guidance on long-term monitoring. The published surveillance guidelines for retinoblastoma encompass both intraocular tumor surveillance and monitoring for secondary malignancies in the heritable population.

Numerous clinical trials are active in retinoblastoma research, as documented in ClinicalTrials.gov data for this condition. Active studies include a Phase 2 trial evaluating intravitreal treatment strategies (NCT05504291, Children's Oncology Group, enrolling through 2028), a comprehensive omics analysis of pediatric solid tumors through the National Cancer Institute (NCT01109394), and a Phase 2 trial evaluating immunotherapy in pediatric populations with advanced conditions including retinoblastoma (NCT04458922). Multiple agents with orphan designation are the subject of ongoing investigations. Additional research encompasses newborn screening research (NCT03655223) with potential relevance to early identification. The overall volume of active clinical trials reflects broad investigational activity in this pediatric cancer.