7. Use of HPV tests in cervical cancer screening and the effect of vaccination
Developments that radically change cervical cancer screening Until recently exfoliative cytology formed the basis for cervical cancer screening and to a major extent fulfilled the criteria defined many years ago for an effective method of screening . Its success has been demonstrated in many countries during the past 50 years ; but recent developments in […]
Atypical and borderline changes
Definitions of borderline and atypical In the BSCC classification The term BNC [borderline nuclear change] is used as a holding category when there is genuine doubt as to whether or not the changes are neoplastic. (Denton et al. 2008). Since the Bethesda system was first introduced (Kurman & Solomon 1988) the category atypical cells of […]
10. Pitfalls in cervical cytology
Classic cytological appearances of high-grade intraepithelial lesions are frequently not encountered in routine practice and there are many mimics of benign and neoplastic changes that may lead to errors in diagnosis. Pitfalls in cervical cytology may conveniently be divided into three categories: Potential false negatives Potential false positives Unnecessary atypical/borderline reports The aim of […]
HPV primary screening
HPV primary screening is an attractive option to health service managers because the results are not subject to inter-observer variation. Also, in the long run, HPV screening may be cheaper than cytology because the costs of personnel, training, update and quality control may be lower. Nevertheless, HPV testing also requires equipment, reagents, training, quality control […]
Distinguishing progressive from reversible lesions
Cytological screening has been so successful in preventing invasive cervical carcinoma that its importance as a health problem tends be overshadowed by the disadvantages and possible risks of screening itself. In England, where screening coverage since the NHS Cervical Screening Programme was officially launched in 1988 has been high, CIN3 has most frequently been found and […]
11. Quality assurance, quality control and quality standards
Quality assurance The maintenance of a desired level of quality in a service [or product] especially by means of attention to every stage of the process of delivery or production (www.oxforddictionaries.com) In order to maintain the desired level of quality in cervical cancer screening, the following systems are required: Quality control: internal measures to […]
References
Arbyn M, Ronco G, Anttila A et al. (2012). Evidence regarding human papillomavirus testing in secondary prevention of cervical cancer. Vaccine 30 (suppl. 5):F88-99. Arbyn M, Roelens J, Cuscheiri K et al. (2013). The APTIMA HPV assay versus the Hybrid Capture 2 test in triage of women with ASC-US or LSIL cervical cytology: a meta-analysis […]
Potential risks of treatment of high-grade CIN
Local ablation or excision of the transformation zone has been highly successful in treating high-grade CIN and greatly reduces the risk of progression to invasive carcinoma but it is not itself without risk (Kyrgiou 2014). It is probable that the increase in second trimester miscarriages due to premature rupture of membranes reported after excision biopsy […]
Uses of HPV testing in triage of cervical cytology
Uses of HPV testing alongside cytology Triage of ASC-US and/or LSIL cytology Test of cure after treatment of high-grade CIN Resolution of uncertainties Primary HPV testing or co-testin The principles of all these methods alongside cytology are similar: HPV is more sensitive than cytology for CIN2+ Early detection of CIN2 is not an end […]
Measurement of accuracy
Measurement of accuracy Measurement of accuracy of screening combines sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of a positive test with respect to a positive outcome (Figure 5.5). The following factors must be considered when assessing measurements of accuracy. The nature of the positive and non-positive test for any given circumstance […]