Objective To observe the high-risk histopathological feature (HRF) and their correlation with prognosis in children with intraocular retinoblastoma (RB) in the intraocular stage after failed eye-preserving treatment and enucleation surgery. MethodsA single-center retrospective case study. From August 2018 to January 2023, 64 children (64 eyes) with advanced intraocular RB who were diagnosed in the ophthalmology department of Beijing Children's Hospital and underwent enucleation surgery after failed eye-preserving treatment were included in the study. The median follow-up time was 51 months. The gender of the children patients, the age of visit and enucleation, International Intraocular Retinoblastoma Classification (IIRC), the initial chemotherapy regimen (hereinafter referred to as "chemotherapy"), the time of enucleation surgery, pathological results, post-enucleation treatment methods and prognosis were collected. The Mann-Whitney U test was used for comparison between groups. Survival analysis was performed using the Kaplan-Meier method, and the log-rank test was used for comparison between groups. ResultsAmong 64 cases and 64 eyes, 370 were male and 27 were female. The age of seeking medical treatment was 20 (11-31) months. The age at which the surgery was performed was 29 (16-40) months. The number of eyes in IIRC stage D and E was 16 and 48 respectively. The initial chemotherapy regimens simply applied (hereinafter referred to as "alone") intravenous systemic chemotherapy (IVC) and ophthalmic artery infusion chemotherapy (IAC) in 40 cases and 11 cases, 13 cases of IVC+IAC. All patients with positive HRF received systemic adjuvant chemotherapy after surgery. There were 37 eyes (57.8%, 37/64) positive for HRF. There was no statistically significant difference in the positive rate of HRF between children in IIRC stage D and stage E (χ2=0.021, P=0.884). Among the 37 eyes with HRF, the numbers of eyes with extensive choroidal invasion, posterior lamina cribrosa optic nerve invasion, scleral invasion and scleral invasion were 17 (45.9%, 17/37), 16 (43.2%, 16/37), 3 (8.1%, 3/37) and 3 (8.1%, 3/37), respectively. During the follow-up period, there were 5 cases (7.8%, 5/64) of extraocular metastasis of the tumor and death, all of which were stage E and had HRF. Among them, the initial treatment plan was IAC for 4 cases, one case of IVC. The survival rates of children among the IVC, IAC or IVC+IAC regimens were 97.5% (39/40), 63.6% (7/11), and 100.0% (13/13) eyes, respectively. The comparison of survival rates among different chemotherapy regimens showed statistically significant differences (χ2=14.233, P＜0.001). The results of survival analysis showed that the cumulative survival rate of those with extensive choroidal invasion, posterior lamina cribrosa optic nerve infiltration, and those who received IAC was significantly lower than that of those without extensive choroidal invasion, posterior lamina cribrosa optic nerve infiltration, and those who received IVC+IAC and IVC (P＜0.05). ConclusionsEye-preserving treatment for children with advanced intraocular RB may increase the positive rate of HRF and the risk of extraocular metastasis. The IVC+IAC eye-protecting treatment plan can improve the survival rate of children.