ABC3 Part II: a review of the new criteria for evaluating cervical cytology in England

Technological advances: Have they improved standards? Review of outcomes from the Welsh cervical screening programme

OBJECTIVES

Introduction of new technologies into cervical screening programmes has allowed more efficient programmes with less resources. We present an overview of screening technologies introduced into the Cervical Screening Wales programme and their evolution over time.

METHODS

Data from the programme's statistical report were used to evaluate its performance over a 17-year period between 2001/02 and 2017/18.

RESULTS

The introduction of liquid-based cytology has had a substantial impact on reducing inadequate sample rates and on increasing the positive predictive value of cytology. Inadequate rates have increased following the implementation of human papilloma virus testing as a triage test for cytology. Further knock-on effects on standard reporting ranges are expected following the introduction of human papilloma virus testing as the primary screening test. New performance standards have been introduced to better reflect the performance of the programme at a time when disease prevalence is expected to fall as women vaccinated against human papilloma virus reach screening age.

CONCLUSIONS

Improvements to this cervical cancer screening programme as illustrated through performance indicator ranges suggest a major role played by technology.

Comparison of Papanicolaou Smear Quality with the Anatomical Spatula and the Cytobrush-Spatula: A Single-Blind Clinical Trial

BACKGROUND

The Papanicolaou (Pap) smear is a standard test for cervical cancer screening; however, the most important challenge is high false-negative results due to inadequate sampling using the Ayres spatula. The cytobrush has been used in combination with the Ayres spatula (cytobrush-spatula) in an attempt to improve the quality of smears with additional costs. The aim of this study was to compare the Pap smear quality with the anatomical spatula (with extended tip) and the cytobrush-spatula.

MATERIALS AND METHODS

This was a prospective single-bind clinical trial. One hundred and ten sexually active women aged between 22 and 65 years were randomized into groups, each having two smears at the same time: one with a cytobrush-spatula and another with an anatomical spatula. Fifty-five patients were randomized to have the anatomical spatula first to obtain their smears and 55 were randomized to have the cytobrush-spatula first to obtain their smears. Slides were assessed by a pathologist.

RESULTS

There was no significant difference in the quality of the smears using the two devices with respect to cellular adequacy (P = 0.3532), absent blood staining (P = 0.7766), presence of endocervical cells (P = 0.3502), and evidence of transformation zone sampling using the Bethesda criteria (0.4028). Kappa analysis shows moderate inter-rater agreement between the two devices by ability to show evidence of transformation zone using British Society for Clinical Cytology and Bethesda criteria.

CONCLUSIONS

There was no significant difference in the quality of smears obtained using the two different methods. The anatomical spatula can be used as a single device in conventional cytology in place of the cytobrush-spatula with the aim of improving the quality of smears without necessarily increasing the cost.

Nationwide survey of cervical cytology laboratory practices in China

INTRODUCTION

Cervical cancer rates in China remain high, with only limited opportunistic screening in urban centers and large mostly unscreened rural areas. Cervical cytology practices in China have been changing over the last decade with introduction of The Bethesda System reporting terminology, liquid-based cytology (LBC), and programs for cervical cytology screening of underserved rural populations. An effort was undertaken for the first time to collect nationwide data on cervical cytology laboratory practices in China, a possible first step toward increased standardization and potential development of nationwide cytology quality benchmarks.

MATERIALS AND METHODS

Data on cervical cytology practices from 1572 laboratories operating in 26 nationwide Provisional Level Administrative Divisions was collected in an online survey approved through the Obstetrics and Gynecology Hospital of Fudan University in Shanghai.

RESULTS

Over 90% of cervical cytology laboratories in China now solely use Bethesda System reporting terminology. LBC is now the most commonly utilized form of cervical cytology, with lower-cost Chinese-manufactured LBC formulations used in almost 70% of laboratories. Nationwide, significantly higher abnormal cytology rates were reported with LBC than with the conventional Papanicolaou smear (CPS); however, the CPS remains a useful low-cost alternative as China strives to extend cervical screening to large underserved rural areas.

CONCLUSIONS

Abnormal cytology rates were not significantly different when different levels of hospitals were compared. The survey identified nationwide opportunities for cytology quality improvement, including low rates of reporting of unsatisfactory cases and low rates for atypical glandular cells.

PPV of an HSIL cervical cytology result in China's largest CAP-certified laboratory

INTRODUCTION

Cervical cancer remains a major health problem in China, where no uniform national standards for cervical cytology quality control exist. This study extends previously reported findings on cervical cytology performance in China's largest independent laboratory to have achieved accreditation under the international Laboratory Accreditation Program of the College of American Pathologists.

MATERIALS AND METHODS

A retrospective study identified high-grade squamous intraepithelial lesion (HSIL) cervical cytology reports between 2007 and 2013 from the Cytology Laboratory, Guangzhou Kingmed Diagnostics. Four liquid-based cytology (LBC) preparations were used in 73% of cases and conventional Papanicolaou tests (CPT) in 27%. Follow-up histopathologic diagnoses after HSIL reports were identified in the laboratory database. The positive predictive value for laboratory HSIL cytology results was determined for follow-up histopathologic diagnoses of cervical intraepithelial neoplasia 2 or worse (CIN2+), a recognized international quality control monitor.

RESULTS

Of 1,804,108 cervical cytology reports, 11,929 HSIL reports (0.66%) were identified. The LBC HSIL rate was 0.79%, which was higher than the CPT HSIL rate of 0.33% (P < 0.001). Follow-up CIN2+ histopathologic diagnoses within 6 months after HSIL were identified in 1994 of 2414 patients (82.6%), including 1860 of 2246 LBC HSIL (82.8%) and 134 of 168 CPT HSIL (79.8%). Cervical cancers were diagnosed on follow-up in 244 of 2414 HSIL cases (10.1%).

CONCLUSIONS

The positive predictive value of HSIL cervical cytology results for follow-up histopathologic CIN2+ was within currently recognized benchmark ranges for cytology laboratories. The high rate of cervical cancer diagnoses likely reflects the largely unscreened population. The College of American Pathologists Laboratory Accreditation Program provided quality standards not otherwise available in many international settings.

ABC3 Part I: a review of the guidelines for terminology, classification and management of cervical cytology in England

The provision of guidance on cytology reporting and evaluation, first outlined in 1995 with the publication of Achievable Standards, Benchmarks for Reporting, and Criteria for Evaluating Cervical Cytopathology (ABC), and subsequently revised and expanded in a second edition in 2000, has been pivotal to the success of the National Health Service Cervical Screening Programme (NHSCSP), ensuring that standards are upheld, and that rigorous evaluation and quality assurance take place. In the last decade, major changes to the NHSCSP, notably the adoption of revised age ranges and screening intervals for all women in England, implementation of liquid-based cytology and, most recently, the decision to introduce high-risk human papillomavirus (HR-HPV) testing for triage of low-grade and borderline (equivalent to 'atypical') cytological abnormalities and test of cure after treatment of cervical intraepithelial neoplasia (CIN) determined that an updated version of ABC was required. The third edition of ABC recommends adoption, with minor modification, of the revised British Society for Clinical Cytology terminology and provides guidance on the management of abnormal cytology results linked to this terminology taking account of HR-HPV testing. To accommodate these changes, expanded result codes, which are electronic codes used to transfer management information to central computers for follow-up, call and recall of individual women, have been developed. Further guidance on specimen adequacy is also provided. Revised performance indicators are described and explained in a separate article by R. Blanks in this issue of Cytopathology. All the changes in ABC3 are designed to support the mission statement of the NHSCSP that 'the objective of cervical screening is to reduce cervical cancer incidence and mortality by screening with a high sensitivity for the detection of CIN2 or worse, whilst maintaining a high specificity'.

Transformation zone sampling rate used as a performance indicator for cervical liquid-based cytology sample-takers

OBJECTIVE

To investigate the sampling performance of individual cervical cytology practitioners using the transformation zone sampling rate (TZSR) as a performance indicator and to assess the impact of dedicated on site training for those identified with a low TZSR.

METHODS

The TZSR was calculated for all practitioners submitting ThinPrep(®) cervical cytology specimens to the Conquest laboratory between January 2010 and November 2011. After excluding those with less than 30 qualifying samples the 10th percentile of the TZSR was calculated. Practitioners with a TZSR below the 10th percentile were visited by a specialist cervical cytology screening facilitator after which the TZSR of these practitioners was closely monitored.

RESULTS

After exclusions there were 175 practitioners who had collected 24 358 qualifying liquid-based cytology (LBC) samples. The average TZSR was 70% (range 12-96%). The 10th percentile was 44%; 18 scored below the 10th percentile. Failure to apply sufficient pressure when sampling was identified as the most common reason for a low TZSR. In some cases there was suspicion that the cervix was not always adequately visualized. Continuous monitoring after assessment identified improvement in the TZSRs of 13/18 practitioners.

CONCLUSIONS

Identification of practitioners with low TZSRs compared with their peers allows these individuals to be selected for personalized observation and training by a specialist in cervical cytology which can lead to an improvement in TZSR. As previous studies show a significant correlation between the TZSR and the detection rate of cytological abnormality it is useful to investigate low TZSRs.