Diagnostic delay worsened survival, disease progression in bilateral retinoblastoma
A longer diagnostic delay from initial symptom presentation to diagnosis was significantly associated with more advanced-stage disease and worse survival among pediatric patients with bilateral retinoblastoma, study results showed.
However, among patients with unilateral retinoblastoma, reducing the diagnostic delay had no effect on survival or stage of the disease.
Manuela A. Orjuela
“Retinoblastoma is usually thought of as one disease, but there is good evidence that unilateral and bilateral retinoblastoma are distinct and progress in different ways,” Manuela A. Orjuela, MD, ScM, assistant professor of pediatrics and environmental health sciences at Columbia University Medical Center, said in a press release.
To assess the effect diagnostic delays have on the extent of disease at diagnosis for unilateral and bilateral retinoblastoma, Orjuela and colleagues followed 179 children with retinoblastoma in Mexico City. The researchers interviewed the children’s parents about initial symptoms and sociodemographic factors.
The researchers classified clinical presentation of retinoblastoma using St. Jude’s, International Staging System (ISS) and International Intraocular Retinoblastoma Classification (IIRC) criteria. In addition, diagnostic delay and sociodemographic factors were surveyed as possible predictors for higher disease stage at diagnosis and OS.
According to study results, in bilateral retinoblastoma, diagnostic delay predicted stage at diagnosis using St. Jude’s and ISS criteria (P<.005 in multivariate regression) and OS (P<.05), but not the extent of intraocular disease according to IIRC criteria.
In contrast, diagnostic delay predicted neither extent of disease nor OS among patients with unilateral disease.
“Our study suggests that screening children for retinoblastoma may not improve outcomes for the majority of patients, particularly for the more common form of the disease affecting one eye,” Orjuela said. “By the time the tumor is visible in the child's eye, vision is infrequently salvageable, and removal of the eye is usually necessary to prevent spread of the disease.”
Indicators of prenatal poverty, including the presence of dirt flooring in the home and lower maternal education, predicted more advanced disease by IIRC criteria for bilateral retinoblastoma, and for unilateral by ISS, and St Jude’s (P<.001) as well as OS (P<.05).
The researchers said these results indicate unilateral and bilateral retinoblastoma differ in factors driving progression and extraretinal extension, possibly due to underlying biological heterogeneity. Furthermore, the divergent effect of social factors on the extent of intra- and extraocular disease depending on laterality could have implications for screening strategies.
“We may need to rethink the costs and benefits of screening programs and consider how to improve survival among children with less-educated parents,” Orjuela said.
Disclosure: The researchers report no relevant financial disclosures.