[Analysis of high-risk histopathologic features of 482 primarily enucleated retinoblastomas]

Objective: To evaluate the high-risk histopathologic features of retinoblastoma eyes enucleated as primary treatment. Methods: Retrospective case series study. An analysis was carried out on the high-risk histopathologic features of 482 primarily enucleated retinoblastoma eyes in Beijing Tongren Eye Center during December 2011 and December 2016. The high-risk histopathologic features included post lamina cribrosa invasion, massive choroidal invasion, anterior segment invasion and extraocular invasion. According to the neovascularization of iris (NVI) in the tissue specimen, the patients were divided into the NVI positive group and negative group. The rates of high-risk histopathologic features in the NVI positive group and negative group were analyzed using the chi-square test. Results: Among 482 children with retinoblastoma, 280 (58.1%) were males and 202 (41.9%) were females. The median age at enucleation surgery was 24 months (range, 1-84 months). Of the 482 primarily enucleated eyes, 184 (38.2%) were classified as high-risk histopathologic features, including 148 (30.7%) with post lamina cribrosa invasion, 15 (3.1%) with optic nerve transection invasion, 66 (13.7%) with massive choroidal invasion, 35 (7.3%) with anterior segment invasion, and 5 (1.0%) with extraocular invasion. NVI was detected in 257 (53.3%) cases and there was a significant relation between high-risk histopathologic features and NVI. The rate of high-risk histopathologic features was significantly higher in the NVI positive group (123 cases, 47.9%) than the NVI negative group (61 cases, 27.1%) (χ(2)=21.883, P=0.001). The rate of post lamina cribrosa invasion was significantly higher in the NVI positive group (110 cases, 42.8%) than the NVI negative group (38 cases, 16.9%) (χ(2)=37.860, P=0.001). Conclusions: In this large sample of patients, about 1/3 of retinoblastoma eyes has high-risk histopathologic features. The NVI positive retinoblastoma is more likely to have high-risk histopathologic features or post lamina cribrosa invasion than the NVI negative retinoblastoma. (Chin J Ophthalmol, 2018, 54: 782-786).