Implementation of the ThinPrep® imaging system in a high‐volume metropolitan laboratory

Abstract

The Papanicolaou test has proven to be the most effective cancer screening test ever developed. However, with a declining number of skilled cytotechnologists, there is an increased need for computer assistance in cervical cancer screening. The ThinPrep Imaging System (Cytyc Corporation, Marlborough, MA) is a unique system that combines computer imaging technology and human interpretive expertise in the review of ThinPrep Pap test slides. The purpose of this study is to report on the introduction and validation of this technology and present data related to the performance and productivity in our laboratory. Following completion of the ThinPrep Imaging System validation protocol, all imaged ThinPrep Pap test results were tracked and compared with year-2003 manually screened results to identify whether the Imaging System was effective in aiding human interpretive skills. Cases rescreened in the 10% random quality control (QC) program from the negative population that showed abnormal cells consistent with low-grade squamous intraepithelial lesion (LSIL) and above were compared with imaged versus non-imaged cases to establish an estimated laboratory false-negative (F/N) rate. The study compared results of 82,063 manually screened ThinPrep Pap tests in 2003 with 84,473 imaged ThinPrep Pap tests in 2004. Results demonstrated a significant increase in LSIL (37%) and high-grade squamous intraepithelial lesion (HSIL) (42%) detection on the Imager cohort. The F/N rate was reduced by half. The evaluation period after validation of the Imager showed a significant increase in LSIL and HSIL detection with the ThinPrep Imaging System compared to manual screening. These results demonstrate that the Imager has the potential to allow the cytotechnologists to detect more disease and reduce the false-negative rate for the laboratory. Although not evaluated in this study, cytotechnologists reported increased job satisfaction.

Effectiveness of the Thin Prep® Imaging System in the detection of adenocarcinoma of the gynecologic system

“…9 Dziura et al and Miller et al also described a significant increase in the detection of histologically proven HSIL in both the atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion (ASC-H) and HSIL cytology categories in their practice. 10,11 An increased accuracy in the detection of HSIL was also reported by Chivukula et al with the use of TIS. 12 Davey et al reported that the TIS detected 1.29 more cases of histologic HSIL per 1000 women screened than conventional cytology.…”

MAVARIC – a comparison of automation-assisted and manual cervical screening: a randomised controlled trial

“…6 As stated in Chapter 1 and shown in Table 1, previous studies comparing automated with manual reading have tended to indicate higher rates of cytological abnormality and some have found increased rates of CIN2+. Some of these studies 23,27 have been performed simply comparing cytological abnormality rates in consecutive periods of time, and others have used a split sample design, 16,24,26 whereby the same sample has been split between a conventional or LBC slide which is manually read and a slide which is subjected to automated reading. Many studies do not use histology as an outcome.…”

“…In the manual-only arm the FMR is by definition equivalent to the MR. Comparison between manual and automated readings in the paired arm The effect of checking on serial readings is shown in Tables [20][21][22][23][24][25][26]. When the MR1 was compared with the FMR, a large proportion of low grades (29.5%) were downgraded to negative.…”

A randomized trial comparing conventional cytology to liquid‐based cytology and computer assistance

“…Previous data in nonrandomized settings have shown better performance of CAS compared with manually read LBC [16][17][18]28,29 and CC. 15,17 In a large prospective Australian 1 Conventional cytology: total n cytologically positives: 93 (60 histologically confirmed, 33 imputed).…”