Use of Fast Transfer Analysis Cartridges for Cervical Sampling and Real Time PCR Based High Risk HPV Testing in Cervical Cancer Prevention - a Feasibility Study from South India

Abstract

Background: Molecular testing for human papillomavirus (HPV) is the most objective and reproducible ofall cervical cancer screening tests and also less demanding in terms of training and quality assurance. However,there is an impending need for cost effective molecular HPV testing methods with sampling ease, easy storagemeasures and minimum turn around times suitable for a low resource setting. Objective : Our aim was toevaluate the feasibility of using a fast transfer analysis (FTA) mini elute cartridge for cervical sampling toidentify high risk HPV by real time PCR and to compare molecular HPV testing and Pap cytology testing topredict histologically confirmed cervical precancer (CIN 2+ lesions) in a cervical cancer prevention program.Materials and
Methods: This was conducted as a pilot study (n=200) on women sampled using FTA mini elutecartridges, genotyped by two different real time PCR assays, detecting 13 high risk HPV (HR HPV) species,including HPV16 along with its physical DNA status. Results obtained from each of the tests were comparedand analysed using suitable statistical tests.
Results: With FTA mini elute cartridge samples HR HPV positivitywas seen in 48/200 (24%). Of these, presence of HPV 16 DNA was observed in 28/48 (58.3%) women. High riskHPV was positive in 20% (37/185) of women with benign cytology and 73.3% (11/15) of women with abnormalcytology findings. A very significant correlation (χ2 = 22.090 ; p=0.000) was observed between cytology and HRHPV findings showing an increasing trend of HR HPV prevalence in 50% (1/2) of LSIL, 75% (3/4) of HSIL and100% (3/3) of SCC. Of the CIN 2+ lesions identified by histopathology, 88.9% (8/9) had HR HPV. A significantassociation (χ2=11.223 ; p=0.001) of HR HPV and histopathologically confirmed CIN 2+ lesions was found.Sensitivity of the two tests were comparable but specificity of Pap testing was better (90.7% vs 70.4%) to predicthistopathologically diagnosed cervical precancers.
Conclusions: The current study explored the feasibility ofusing a FTA mini elute cartridge for cervical sampling for the first time in India as a part of a community basedcervical cancer prevention program. We suggest that FTA based sampling is suitable and feasible for real timebased HPV testing. Molecular HR HPV testing can be more sensitive and useful to identify high risk womenrequiring Pap testing which is more specific to detect histologically confirmed cervical precancer.

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