Abstract B63: Survivorship, vision, and eye salvage following pars plana vitrectomy for residual active or recurrent retinoblastoma
Authors: Zhao Junyang , Feng Zhao Xun , Li Qiyan , Wu Songyi , Jin Liwen , Gallie Brenda L. 
Published: August 2020

Abstract
Introduction: Intraocular surgery has long been taboo in the management of eyes with retinoblastoma due to concern of extraocular spread that carries poor survivorship. Pars plana vitrectomy (PPV) and tumor endoresection has recently emerged in China as an effective surgical treatment to salvage eyes with tumor resistant to chemotherapy, the current standard of care. To investigate the safety and efficacy of this novel treatment, we studied survivorship, visual acuity, and eye salvage rate of retinoblastoma children/eyes treated with PPV.
Methods: Outcomes were reviewed for 227 children (247 eyes) treated with PPV and endoresection for residual active tumor or recurrent tumor following chemotherapy at 29 Chinese centers between 2013 and 2014.
Results: At 5 years following PPV, 14 patients died, 8 related to the eye that had PPV. The 5-year overall survival rate following PPV was 93.7% (95% CI: 90.4% to 97.0%). The 5-year PPV eye-related survival rate (PPVSR) was 96.3% (95% CI: 93.8% to 98.9%). Children with PPV for residual active tumor had better survival than those with PPV for recurrent tumor (5-year PPVSR 98.1% vs. 91.4%, P = .021). Children with 1 to 3 cycles of neoadjuvant chemotherapy (intra-arterial or systemic chemotherapy) prior to PPV had similar survival to children with ≥4 cycles of chemotherapy (98.2% vs. 93.7%, P = .093). Children with adjuvant systemic chemotherapy following PPV had 100% (95% CI: 93.5% to 100%) 5-year PPVSR, not significantly higher than those without adjuvant chemotherapy (100% vs. 94.8%, P = .102). Of 94 eyes with partial or no retinectomy and documented visual acuity, the post-PPV visual acuity was 20/20-20/60 (23, 24%); 20/7-20/160 (6, 6%); 20/17-20/400 (9, 10%); counting fingers, hand motion, or light perception vision (42, 45%); and no light perception (NLP) (14, 15%). Complete retinectomy was performed on 93 of 247 (37.7%) eyes that, as expected, had NLP. The 5-year eye salvage rate following PPV was 80.7% (95% CI: 75.5% to 85.9%). PPV for residual active tumor and recurrent tumor had similar eye salvage rate (82.0% vs. 76.8%, P = .372). Eyes with International Intraocular Retinoblastoma Classification (IIRC) A, B, or C staging had better salvage rate than eyes with IIRC D or E staging (100.0% vs. 78.1%, P = .005). Eyes that received 1 to 3 cycles and ≥4 cycles of neoadjuvant chemotherapy had similar salvage rate (81.4% vs. 79.8%, P = .796).
Conclusion: We observed that PPV salvaged 80.7% of eyes with residual active tumor after primary chemotherapy or recurrent tumor after remission. The 5-year eye-specific survival was 96.3%, comparable to survivorship using other treatment modalities. More cycles of neoadjuvant chemotherapy did not improve survivorship or eye salvage rate. In this cohort, all children with adjuvant chemotherapy following PPV survived at 5 years. PPV may be a game changer to improve health outcomes of patients with retinoblastoma, with the potential to become the new standard of care.
Citation Format: Junyang Zhao, Zhao Xun Feng, Qiyan Li, Songyi Wu, Liwen Jin, Brenda L. Gallie. Survivorship, vision, and eye salvage following pars plana vitrectomy for residual active or recurrent retinoblastoma [abstract]. In: Proceedings of the AACR Special Conference on the Advances in Pediatric Cancer Research; 2019 Sep 17-20; Montreal, QC, Canada. Philadelphia (PA): AACR; Cancer Res 2020;80(14 Suppl):Abstract nr B63.