Outcomes of Systemic Bevacizumab in Radiation-Induced Optic Neuropathy, Case Series

Radiation-induced optic neuropathy (RON) is an uncommon delayed ischemic complication after radiation to the optic nerve, which typically leads to devastating vision loss.1,2 There is no universally accepted treatment modality for RON, but several case reports have shown promising results with systemic bevacizumab.3,4 We report the outcomes of six RON cases treated with systemic bevacizumab.

Poster 3 Outcomes of Systemic Bevacizumab in Radiation-Induced Optic Neuropathy, Case Series Ahmad AlAmeer 1, Amanda Henderson 2, Andrew Carey 3 1 wilmer eye/JOHNS HOPKINS HOSPITAL, 2 Wilmer Eye Institute, Johns Hopkins, 3 Johns Hopkins Wilmer Eye Institute Introduction: Radiation-induced optic neuropathy (RON) is an uncommon delayed ischemic complication after radiation to the optic nerve, which typically leads to devastating vision loss.1,2 There is no universally accepted treatment modality for RON, but several case reports have shown promising results with systemic bevacizumab.3,4 We report the outcomes of six RON cases treated with systemic bevacizumab. Description of Cases: A total of six cases (age range: 51-77 years old) were identified from August 2016 to August 2021. Two cases received whole-brain radiotherapy (total radiation dose (TD): 30 Gy in 10 fractions) for metastatic non-small cell lung carcinoma and metastatic bladder cancer. Two cases received intensity-modulated radiotherapy for temporal lobe glioblastoma multiforme (TD: 60 Gy in 30 fractions) and spheno-orbital meningioma (TD: 47.6 Gy in 29 fractions). Two cases received intensity-modulated proton therapy for esthesioneuroblastoma (TD: 70 Gy) and spheno-orbital meningioma (TR: 5D Gy in 29 fractions). RON was diagnosed 8 to 36 months after radiotherapy, which was based on clinical suspicion and MRI finding of optic nerve enhancement. Bevacizumab IV 5-10 mg/kg every 2-3 weeks for four cycles was initiated within 2 weeks of vision loss in 4 cases, and within 2-3 months in 2 cases. Improvement of visual function was not observed, but stabilization of vision was noted in three cases (Final BCVA 20/25, 20/50, and counting fingers). Two cases progressed to NLP from 20/30 and counting finger vision, and one case progressed to hand motion vision from 2/200. The fourth cycle of bevacizumab was withheld in three patients due to stroke, renal stone, and renal disease worsening. Conclusions, including unique features of the case: Systemic bevacizumab failed to improve the visual function in our series. However, stabilization was achieved in three of six cases. Risks and benefits of bevacizumab in each individual case should be considered before starting this chemotherapeutic agent in the setting of RON. References: References: 1. Mihalcea O, Arnold AC. Side effect of head and neck radiotherapy: optic neuropathy. Oftalmologia. 2008;52(1):36-40. 2. Miller NR. Radiation-induced optic neuropathy: still no treatment. Clin Exp Ophthalmol. 2004;32(3):233-235. doi:10.1111/j.1442-9071.2004.00809. 3. Farooq O, Lincoff NS, Saikali N, Prasad D, Miletich RS, Mechtler LL. Novel treatment for radiation optic neuropathy with intravenous bevacizumab. J Neuroophthalmol. 2012;32(4):321-324. doi:10.1097/WNO.0b013e3182607381 4. Dutta P, Dhandapani S, Kumar N, Gupta P, Ahuja C, Mukherjee KK. Bevacizumab for Radiation-Induced Optic Neuritis Among Aggressive Residual/Recurrent Suprasellar Tumors: More Than a Mere Antineoplastic Effect. World Neurosurg. 2017;107:1044.e5-1044.e10. doi:10.1016/j.wneu.2017.07.111 Keywords: Optic neuropathy, Chemotherapy and radiation injury, Skull base, Tumors Financial Disclosures: The authors had no disclosures. Grant Support: None. Contact Information: Ahmad M. AlAmeer, [e-mail] 68 | North American Neuro-Ophthalmology Society