Detection of HPV Subtypes by Mass Spectrometry: A Reliable Tool for Routine Diagnostics

Background Recently the U:S Food and Drug Administration has approved high-risk Human Papilloma Virus (HPV) tests as a primary screening tool for cervical cancer in women aged 25-65 years, without a simultaneous Pap smear. Thus, it is tempting to speculate that pathologists and molecular biologist will be faced with a rising number of HPV testings in the near future. Therefore test systems are required that detect high- and low-risk HPV subtypes with high specificity and sensitivity in a time and cost effective manner. Methods We developed a custom designed assay for routine mass-spectrometric (MS) (MassARRAY, Agena Bioscience) analysis to test for the presence/absence of 19 specific HPV infections and compared the results to hybridization assays (COBAS and Chipron). In total 45 Formalin fixed paraffin embedded (FFPE) tissue samples and 10 Pap smear liquid samples were analyzed. Moreover we tested three different isolation techniques with variable hands-on-time (from 5-45 min) and compared the results. Results All high risk HPV subtypes detected by the COBAS or the Chipron system were also detected by MS. MS outperformed the number of HPV subtypes detected when a time consuming, but very effective DNA purification step had been applied. In all patients HPV infections were found. Conclusions MS is a valuable method to detect HPV subtypes in a high throughput setting in FFPE samples and in Pap smears.