Combining Transoral Nasopharyngeal Brush and Plasma Epstein‐Barr Virus DNA in Detecting Locally Recurrent Nasopharyngeal Carcinoma

Abstract Objective To evaluate the sensitivities and specificities of Epstein‐Barr virus (EBV) DNA in the detection of locally recurrent or persistent nasopharyngeal carcinoma (NPC) through nasopharyngeal (NP) brush biopsy and plasma, respectively, and whether a combination of both would be superior to the individual tests. Study Design A case‐control study was conducted from September 2016 to June 2022. Setting A multicentre study at 3 tertiary referral centers in Hong Kong was conducted by the Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong. Methods Twenty‐seven patients with biopsy‐confirmed locally recurrent NPC were recruited as study subjects. Magnetic resonance imaging was performed to rule out regional recurrence. The control group consisted of 58 patients with a prior history of NPC who were now disease‐free based on endoscopic and imaging findings. Patients underwent both the transoral NP brush (NP Screen®) and blood for plasma Epstein‐Barr DNA levels. Results The sensitivity and specificity of the combined modalities were 84.62% and 85.19%, respectively. The positive predictive value was 73.33% and the negative predictive value was 92.0%. Conclusion The combination of NP brush biopsy and plasma EBV DNA is potentially an additional surveillance modality in detecting the local recurrence of NPC. Further study with a larger sample size would be required to validate the cutoff values.