Evaluation of HPV Positivity Rate as a Quality Assurance Measure for a Cytopathology Lab.
Anne Das, Amar Agadi, Shagufta Khan, Fred Lucas. University of Cincinnati College of Medicine, OH; Tristate Laboratories, Cincinnati, OH
Background: With the advent of validated techniques for HPV testing, a new metric to monitor the accuracy of ASCUS(Atypical Squamous Cells of Undetermined Significance) diagnoses has been introduced. An application of this metric in our lab with a mixed demographic offers a new perspective to the existing studies. The CAP QProbes study of 68 institutions classifies HPV positivity rates for ASCUS cases by different demographic metrics including type of institution and patient age. The overall HPV positivity rate for their study, including teaching and non-teaching institutions, is 43.74% (SD of 17.77%).
Design: We compared the results of 814 reflex HR-HPV(High Risk HPV) tests over a 6 month period in 2010 for ASCUS diagnosis cases to the national data reported by the ALTS trial and the CAP QProbes study. The purpose of this comparison was to evaluate whether our mixed patient demographics contribute to the deviation in our HPV positivity rate.
Results: 1. Table below shows that the HPV positivity rates (HPR) of university clinics(UC) and suburban/peripheral clinics (PC) cases deviate from the ALTS and CAP QProbes study as well as from each other.
|UC||PC||WTD AVG UC/PC||ALTS Trial||CAP QProbes study|
|HPV positivity rate %||51.5||25.2||29||50.6||43.74|
|# of cases||127||687||814||3488||68 institutions|