Predicting Schwannoma Growth in a Tumor Model Using Targeted Imaging. Issue 5 (June 2021)

• Record Type: Journal Article
• Authors: Morrison, Daniel R.; Sorace, Anna G.; Hamilton, Ellis; Moore, Lindsay S.; Houson, Hailey A.; Udayakumar, Neha; Ovaitt, Alyssa; Warram, Jason M.; Walsh, Erika M.
• Is Part Of: Otology & neurotology. Volume 42:Issue 5(2021)
• Publication Date: 2021-06
• Subjects: Fluorescent -- Human Epithelial Growth Factor Receptor 2 -- Imaging -- Neurosurgery -- Neurotology -- Schwannoma -- Vascular endothelial growth factor -- Vestibular; Otology -- Periodicals; Ear -- Diseases -- Periodicals; Skull base -- Surgery -- Periodicals; 617.8005
• DOI: 10.1097/MAO.0000000000003063
• Languages: English
• ISSNs: 1531-7129

Abstract

Abstract : Introduction: Vestibular schwannoma (VS) is a common pathology encountered in neurotology clinics. Many patients are observed with a "wait and scan" approach. Previous efforts to determine radiographic indicators of future growth have been unsuccessful. Using a mouse subcutaneous tumor model, we seek to determine if fluorescent imaging with directed immunotargets could be used to predict schwannoma growth rate. Methods: Anti-VEGFR2 and anti-Her2/Neu monoclonal antibodies were covalently linked to a near-infrared probe (IRDye800). Immunodeficient mice underwent subcutaneous injections with a rat-derived schwann (R3) cell line. When tumor growth was evident, either Anti-VEGFR2-IRDye800, anti-Her2/Neu-IRDye800, or Immunoglobulin G (IgG) Isotype-IRDye800 (control) were injected via tail vein. The mice were serially imaged in a closed field near-IR device. Fluorescent data were analyzed for tumor signal and correlated with tumor sie and growth rate. Heterogeneity of fluorescent tumor signal was also assessed. Results: In both anti-VEGFR2 and anti-Her2/Neu groups, there were strong correlations between day 1 mean tumor fluorescence and eventual maximum tumor volume ( p = 0.002, 0.001; r 2 = 0.92, 0.86). There was also strong correlation with maximum tumor signal on day 1 and maximum tumor volume ( p = 0.003, 0.008; r 2 = 0.90, 0.91). There was no such correlation in the control group ( p = 0.99, 0.75; r 2 = 0.0002, 0.028). Conclusion: Given the potential morbidity in VS intervention, observation is an appropriate approach for patients with slow-growing or stagnant tumors. We seek to identify immunotargets in a murine model that show promise in predicting schwannoma growth with advanced imaging techniques. Both Her2/Neu and VEGFR2 correlated strongly wth tumor size and growth rates and are promising targets that merit further investigation. Abstract : Supplemental Digital Content is available in the text