MonoPrep Pap Test for the Detection of Cervical Cancer and Its Precursors
MonoPrep Pap Test for the Detection of Cervical Cancer and Its Precursors
The MonoPrep Pap Test (MPPT; MonoGen, Lincolnshire, IL) is a novel, liquid-based specimen collection and processing technology for cytologic and molecular testing. Its usefulness in the detection of cervical cancer and its precursors was evaluated in a multicenter, masked, adjudicated, split-sample study of 10,739 samples. After preparation of a conventional smear, the residuum on the collection device was rinsed into a collection vial from which an MPPT slide was prepared. Accuracy was assessed by masked reference interpretation by an independent pathologist. Slides prepared by MPPT, compared with smears, yielded statistically significant increases in relative sensitivity for atypical squamous cells of undetermined significance and worse, atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion/atypical glandular cells and worse, and low-grade squamous intraepithelial lesion and worse. There was no significant difference in relative specificity. MPPT provided a 58% reduction in unsatisfactory slides. There was no significant difference in the presentation of endocervical/transformation zone component or the detection of benign conditions. The MPPT is a promising new liquid-based technology for cervical cancer screening.
Three liquid-based Papanicolaou (Pap) tests are approved for use in the United States as replacements for the conventional Pap smear: the ThinPrep (Cytyc, Marlborough, MA), SurePath (BD Diagnostics-TriPath, Burlington, NC), and MonoPrep Pap (MonoGen, Lincolnshire, IL) tests. Liquid-based Pap tests were originally developed to facilitate the computerized screening of Pap slides because the identification and classification of cells from optical density measurements is challenging with conventional smears in which the thickness and overlap of cells are poorly controlled. Cell identification and classification by image analysis are much less problematic with the "thin layers" produced by liquid-based preparation methods.
Aside from their suitability for automated screening, liquid-based Pap tests alone, when compared with smears, were shown to increase the sensitivity of the Pap test in the detection of epithelial cell abnormalities. Thus, in 1996, the US Food and Drug Administration (FDA) approved the first liquid-based Pap test, the ThinPrep, as a replacement for the smear. In 1999, another liquid-based Pap test, the SurePath, formerly known as AutoCyte PREP, was also approved as a replacement for the smear. In the United States, the majority of Pap tests are performed using liquid-based methods rather than the smear.
In March 2006, the FDA approved the most recent liquid-based preparation, the MonoPrep Pap Test (MPPT). This report summarizes some of the results of a multicenter, masked, adjudicated, split-sample study performed to test the effectiveness of the MPPT. In this report (part I), the accuracy of the MonoPrep is compared with that of a conventional smear as adjudicated by a reference pathologist. Part II will review its accuracy based on histologic correlation, and Part III will summarize data on human papillomavirus (HPV) correlation.
Abstract and Introduction
Abstract
The MonoPrep Pap Test (MPPT; MonoGen, Lincolnshire, IL) is a novel, liquid-based specimen collection and processing technology for cytologic and molecular testing. Its usefulness in the detection of cervical cancer and its precursors was evaluated in a multicenter, masked, adjudicated, split-sample study of 10,739 samples. After preparation of a conventional smear, the residuum on the collection device was rinsed into a collection vial from which an MPPT slide was prepared. Accuracy was assessed by masked reference interpretation by an independent pathologist. Slides prepared by MPPT, compared with smears, yielded statistically significant increases in relative sensitivity for atypical squamous cells of undetermined significance and worse, atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion/atypical glandular cells and worse, and low-grade squamous intraepithelial lesion and worse. There was no significant difference in relative specificity. MPPT provided a 58% reduction in unsatisfactory slides. There was no significant difference in the presentation of endocervical/transformation zone component or the detection of benign conditions. The MPPT is a promising new liquid-based technology for cervical cancer screening.
Introduction
Three liquid-based Papanicolaou (Pap) tests are approved for use in the United States as replacements for the conventional Pap smear: the ThinPrep (Cytyc, Marlborough, MA), SurePath (BD Diagnostics-TriPath, Burlington, NC), and MonoPrep Pap (MonoGen, Lincolnshire, IL) tests. Liquid-based Pap tests were originally developed to facilitate the computerized screening of Pap slides because the identification and classification of cells from optical density measurements is challenging with conventional smears in which the thickness and overlap of cells are poorly controlled. Cell identification and classification by image analysis are much less problematic with the "thin layers" produced by liquid-based preparation methods.
Aside from their suitability for automated screening, liquid-based Pap tests alone, when compared with smears, were shown to increase the sensitivity of the Pap test in the detection of epithelial cell abnormalities. Thus, in 1996, the US Food and Drug Administration (FDA) approved the first liquid-based Pap test, the ThinPrep, as a replacement for the smear. In 1999, another liquid-based Pap test, the SurePath, formerly known as AutoCyte PREP, was also approved as a replacement for the smear. In the United States, the majority of Pap tests are performed using liquid-based methods rather than the smear.
In March 2006, the FDA approved the most recent liquid-based preparation, the MonoPrep Pap Test (MPPT). This report summarizes some of the results of a multicenter, masked, adjudicated, split-sample study performed to test the effectiveness of the MPPT. In this report (part I), the accuracy of the MonoPrep is compared with that of a conventional smear as adjudicated by a reference pathologist. Part II will review its accuracy based on histologic correlation, and Part III will summarize data on human papillomavirus (HPV) correlation.
