Ocular survival after intra-arterial chemotherapy for retinoblastoma improves with accrual of experience and programmatic evolution.

BACKGROUND: Intra-arterial chemotherapy (IAC) for the treatment of intraocular retinoblastoma has gained recognition as a method to improve ocular salvage; however, there is a paucity of evidence supporting treatment factors prognosticating ocular survival. METHODS: All patients with retinoblastoma treated with IAC at a single institution between December 2008 and December 2019 were evaluated. Patient demographics, tumor classification, prior treatments, procedural data, other non-IAC therapies, adverse reactions, procedural complications, ocular outcomes, and overall survival were assessed via retrospective chart review. Factors suggestive of increased ocular survival were identified via univariate and multivariate analyses. The impact of accrued treatment experience was evaluated by grouping eyes by the respective year, IAC treatment was initiated. RESULTS: Forty-nine eyes of 43 patients were treated for retinoblastoma with IAC (256 total procedures). At least grade 3 neutropenia was observed following 19% of IAC procedures. The risk of neutropenia was not statistically different between single or multidrug IAC. Comparing those who received balloon-assisted intra-arterial chemotherapy (bIAC) in more than two-thirds of cycles to those who did not, the risk of arterial access site complications was not statistically different. Multivariate analysis revealed a significantly lower risk of enucleation associated with treatment era in years (hazard ratio [HR] = 0.52-1.00, p < .05) and laser therapies (HR = 0.02-0.60, p < .05). CONCLUSIONS: Ocular survival rates in patients treated with IAC for retinoblastoma at our institution have increased over time. Accrued treatment experience and programmatic changes have likely contributed. Larger, prospective series may lead to a better understanding of factors that consistently contribute to better ocular salvage.

One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates.

The goal of the following procedure is to provide a demonstration of the one-pot conversion of a 2-azido-1-nitrate-ester to a trichloroacetimidate glycosyl donor. Following azido-nitration of a glycal, the product 2-azido-1-nitrate ester can be hydrolyzed under microwave-assisted irradiation. This transformation is usually achieved using strongly nucleophilic reagents and extended reaction times. Microwave irradiation induces hydrolysis, in the absence of reagents, with short reaction times. Following denitration, the intermediate anomeric alcohol is converted, in the same pot, to the corresponding 2-azido-1-trichloroacetimidate.