Lag Time Between Onset of First Symptom and Treatment of Retinoblastoma: Outcomes at Three Years from Recruitment.

To evaluate the effect of lag time between diagnosis of retinoblastoma (RB) and treatment in patients from 10 countries. Prospective study of 692 treatment-naïve RB patients from 10 countries followed up for 3 years from recruitment. The mean lag time from the onset of the first symptom to visit to the RB treatment center was 150 days. The mean follow-up duration was 26 months (median, 32 months; range, <1-51 months). A higher socioeconomic status of the country was associated with a lower risk of enucleation: Lower-middle-income countries vs. low-income countries (p<.001), Upper-middle-income vs. low-income countries (p = .009), and high-income countries vs. low-income countries (p = .014). A greater AJCC stage was associated with a greater risk of enucleation: T2 vs. T1 (p<.001) and T3 vs. T1 (p<.001). Increased lag time (p<.001) and AJCC T4 stage (T4 vs. T2; p<.001) were associated with increased risk of death. By Kaplan-Meier analysis, the cumulative incidence of enucleation at 3 months, 1 year, and 3 years was 49%, 55%, and 61%, respectively; and survival at 1, 2, and 3 years was 92%, 88%, and 87%, respectively. Three-year Kaplan-Meier survival estimates were 95% with a lag time of <3 months vs. 83% with a lag time of 3-12 months vs. 62% with a lag time of >12 months. A lower socioeconomic status and greater AJCC stage were associated with an increased risk of enucleation. Increased lag time from the onset of the first symptom to visit the RB treatment center and AJCC T4 stage were associated with an increased risk of death from RB.