Abstract Cancer of the oral cavity and pharynx was the 9th most common cancer in US males in 2009, and has a 5-year survival rate of 50%, which has remained relatively unchanged for several decades. This low survival rate is partly attributed to patients being diagnosed in advanced stages of the disease, and has lead to the consensus that early detection and diagnosis are key to improving survival. The objective of this research was to use a technique called dielectrophoresis (DEP) to study the electrophysiological characteristics of cells from normal, dysplastic and cancerous oral mucosa, collected via oral brush biopsies (OBBs) from patients with oral squamous cell carcinoma (OSCC) or oral epithelial dysplasia (OED), and from healthy volunteers. DEP testing involved applying AC electric fields to the cells collected via brush biopsies, whilst they were suspended in a conductivity-controlled medium. Interactions between the cells and the electric field resulted in cellular movement, dependent both on frequency of the applied electric field and cell properties. The electrophysiological properties of the cells’ cytoplasm and membrane were then deduced as a result of analysing this cellular movement. After obtaining favourable ethical opinions from all institutions involved, OBB samples were collected from 61 patients with OSCC or OED and from 12 healthy volunteers. At the time of abstract submission, 38 OSCC OBB and 12 OED OBB samples (grouped as Abnormal samples, N = 50), 36 patient-matched OBB samples of visually healthy oral mucosa from OSCC and OED patients and 21 OBB samples from the mucosa of healthy volunteers (grouped as Normal samples, N = 57) had been successfully tested and studied using DEP. Statistical analysis of these preliminary results of DEP testing showed statistically significant differences (p<0.025) in cell membrane electrophysiological properties of Abnormal versus Normal OBB samples, OSCC samples versus Healthy Normal samples and OED samples versus Healthy Normal samples. These preliminary results suggest that DEP testing of oral brush biopsies has the potential to form the basis of a minimally invasive bench-top diagnostic tool for rapid identification of cancerous and potentially malignant lesions. Citation Format: Karen A. Graham, Stefano Fedele, Stephen R. Porter, Nicholas Kalavrezos, James A. McCaul, Mark P. Lewis, Michael P. Hughes, Fatima H. Labeed. Could dielectrophoretic testing of oral brush biopsies aid early detection and diagnosis of oral cancer?. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4139. doi:10.1158/1538-7445.AM2013-4139