Retrospective case-control study of viral pathogen screening in proliferative verrucous leukoplakia lesions

Objective This study aimed to survey the presence of known oncoviruses in oral biopsies from patients diagnosed with the aetiologically undetermined proliferative verrucous leukoplakia and compare results to those from milder oral leukoplakia (OL) cases, oral squamous cell carcinoma, a common outcome of the lesions of interest, and healthy controls. Design Blind, retrospective, case–control study. Setting A stomatology unit in an academic Hospital and a Public Health laboratory. Participants Forty patients were divided in four groups. Ten patients had been diagnosed with proliferative verrucous leukoplakia, 10 with OL and 10 with OSCC, and 10 were healthy subjects. Main outcome measures The presence or absence of oncovirus DNA was assayed with the amplification of viral genetic markers using PCR and subsequent gel electrophoresis confirmation. Amplified fragments were sequenced and identified bioinformatically. Results No DNA from the herpesvirus, papillomavirus or polyomavirus species was detected in the samples. Conclusions No association between proliferative verrucous leukoplakia and target viruses was detected. A higher throughput viral metagenomic approach may prove valuable for future analyses, as it would not be restricted to a priori knowledge of potential targets.