We sought to test the diagnostic efficacy of a low-cost, liquid-based cervical cytology that could be implemented in low-resource settings.
A prospective, split-sample Pap study was performed in 595 women attending a cervical cancer screening clinic in rural El Salvador. Collected cervical samples were used to make a conventional Pap (cell sample directly to glass slide), whereas residual material was used to make the liquid-based sample using the ClearPrep method. Selected samples were tested from the residual sample of the liquid-based collection for the presence of high-risk Human papillomaviruses.
Of 595 patients, 570 were interpreted with the same diagnosis between the 2 methods (95.8% agreement). There were comparable numbers of unsatisfactory cases; however, ClearPrep significantly increased detection of low-grade squamous intraepithelial lesions and decreased the diagnoses of atypical squamous cells of undetermined significance. ClearPrep identified an equivalent number of high-grade squamous intraepithelial lesion cases as the conventional Pap. High-risk human papillomavirus was identified in all cases of high-grade squamous intraepithelial lesion, adenocarcinoma in situ, and cancer as well as in 78% of low-grade squamous intraepithelial lesions out of the residual fluid of the ClearPrep vials.
The low-cost ClearPrep Pap test demonstrated equivalent detection of squamous intraepithelial lesions when compared with the conventional Pap smear and demonstrated the potential for ancillary molecular testing. The test seems a viable option for implementation in low-resource settings.
The low-cost ClearPrep Pap test demonstrated equivalent detection of SIL when compared with the conventional Pap smear and demonstrated the potential for ancillary molecular testing.
1Division of Cytopathology, Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA; 2Department of Obstetrics and Gynecology, University of Pittsburgh Medical Center/Basic Health International, Pittsburgh, PA; and 3Health International, San Salvador, El Salvador
Reprint requests to: Juan C. Felix, MD, Department of Pathology, LAC + USC Medical Center, 1100 N State St, Clinic Tower A7A, Los Angeles, CA 90033. E-mail: firstname.lastname@example.org
ClearPrep supported this study through a donation of vials for liquid cytology.
The authors have declared they have no conflicts of interest.