Intra-arterial chemotherapy for retinoblastoma.

Intra-arterial chemotherapy (IAC) for retinoblastoma is a minimally invasive and chemotherapeutic approach resulting in eye salvage and vision restoration or preservation. Moreover, IAC has proven to effectively treat advanced retinoblastoma while not compromising patient survival. Our institutional experience with IAC for retinoblastoma has included over 500 patients and over 2400 intra-arterial infusions. Each infusion is completed with the use of a micropuncture for arterial access and microcatheter for infusion, eliminating the need for guide catheters and related complications (video 1). This treatment modality has resulted in >95% ocular survival and reduces enucleation to <5% for this population. In addition to local therapy, including cryotherapy, intravitreal chemotherapy, or laser treatments, by the ophthalmologist, IAC has become an important component of comprehensive multidisciplinary and multimodal therapy for this disease. For what used to require a possibly vision-sacrificing procedure, retinoblastoma treated with IAC minimizes the need for enucleation while maximizing both patient and ocular survival.DC1SP110.1136/neurintsurg-2022-018957.supp1Supplementary data neurintsurg;15/3/303/V1F1V1Video 1 .

Delayed intracranial aneurysm formation after cardiac myxoma resection: Report of two cases and review of the literature.

Myxomas are slowly growing benign neoplasms and represent the most common tumor of the heart. Embolism from cardiac myxoma occurs in 30-45% of patients and in at least half of the cases cerebral arteries are affected leading mainly to embolic ischemic strokes and rarely to delayed intracranial aneurysm formation. We present two cases with delayed intracranial aneurysmal formation 14 years and 18 years after cardiac myxoma resection. To the best of our knowledge these two cases represent the longest time interval between aneurysm detection after complete cardiac myxoma resection with no recurrence confirmed by transesophageal echocardiogram. Our study also provides the longest clinical and radiological follow-up on this type of lesion.

Orthotopic glioblastoma stem-like cell xenograft model in mice to evaluate intra-arterial delivery of bevacizumab: from bedside to bench.

Bevacizumab (BV), a humanized monocolonal antibody directed against vascular endothelial growth factor (VEGF), is a standard intravenous (IV) treatment for recurrent glioblastoma multiforme (GBM), that has been introduced recently as an intra-arterial (IA) treatment modality in humans. Since preclinical models have not been reported, we sought to develop a tumor stem cell (TSC) xenograft model to investigate IA BV delivery in vivo. Firefly luciferase transduced patient TSC were injected into the cortex of 35 nude mice. Tumor growth was monitored weekly using bioluminescence imaging. Mice were treated with either intraperitoneal (IP) or IA BV, with or without blood-brain barrier disruption (BBBD), or with IP saline injection (controls). Tumor tissue was analyzed using immunohistochemistry and western blot techniques. Tumor formation occurred in 31 of 35 (89%) mice with a significant signal increase over time (p=0.018). Post mortem histology revealed an infiltrative growth of TSC xenografts in a similar pattern compared to the primary human GBM. Tumor tissue analyzed at 24 hours after treatment revealed that IA BV treatment with BBBD led to a significantly higher intratumoral BV concentration compared to IA BV alone, IP BV or controls (p<0.05). Thus, we have developed a TSC-based xenograft mouse model that allows us to study IA chemotherapy. However, further studies are needed to analyze the treatment effects after IA BV to assess tumor progression and overall animal survival.

Persistence of retinal function after selective ophthalmic artery chemotherapy infusion for retinoblastoma.

PURPOSE: To assess potential retinal viability by electroretinography following selective ophthalmic artery chemotherapy infusion for retinoblastoma. METHODS: Uncontrolled prospective case series. Patients with advanced retinoblastoma were offered elective ophthalmic artery chemotherapy infusion treatment under an IRB-approved protocol as an alternative to enucleation. The ophthalmic artery was cannulated under fluoroscopic control, and chemotherapeutic agents (melphalan and occasionally carboplatin) were directly infused at doses resulting in very high local tissue concentrations, but low systemic drug levels. Eyes were examined under anesthesia at 1-month intervals, and re-treated as indicated, up to a maximum of six infusions. Electroretinograms were obtained during examination under anesthesia, using ERG-jet contact lens electrodes and a hand-held mini-ganzfeld stimulator. The ERG protocol was similar to ISCEV standards except for briefer adaptation times as necessary to reduce the total anesthesia duration. RESULTS: We report initial results in the first ten patients attempted. Nine eyes were successfully cannulated and perfused. ERG data for these nine patients are reported. [Clinical results have been published elsewhere.] Follow up ranged from 3 to 14 months. Extensive, often total, retinal detachments were present in many of the treated eyes. While regression of tumor mass and vitreous seeds was observed in nearly all the patients, retinal detachment occasionally persisted. ERG responses were extinguished in these eyes. Eyes with largely attached retinas, notwithstanding the presence of large tumors at baseline, remained free of detachment after treatment. Normal or near-normal ERGs in these eyes were repeatedly obtained. Recovery of ERG amplitudes was observed in three patients following treatment. CONCLUSIONS: Retinal function can persist and even recover following selective ophthalmic artery chemotherapy infusion for retinoblastoma. Further work is indicated to determine optimal dosing regimens, maximal tolerated dosage, and subsequent visual function in these patients.