QA and QC of the complete cervical screening process
Protocols for quality control (QC) and quality assurance (QA) A pathology test that screens an entire healthy population to find the few with disease must have clearly defined protocols for QA and QC in order to become an acceptable and viable screening test. The same protocols are required for cytology as a triage test […]
Processing cytology samples in the laboratory
Processing cytology samples involves reception of the specimen and request form, preparation of slides for microscopic examination, staining, screening and reporting the slides. All these processes are subject to quality control and quality assurance measures. Reception of specimen and request form Details on specimen and form are checked to make sure they match. Specimen […]
References
Arbyn M, Herbert A, Schenck U et al. European guidelines for quality assurance in cervical cancer screening: recommendations for collecting samples for conventional and liquid-based cytology. Cytopathology 2007;18:133-9. Arbyn M, Bergeron C, Klinkhamer P et al. Liquid compared with conventional cervical cytology: a systemic review and meta-analysis. Obstet Gynecol 2008;111:167-77. Davey E, Barratt A, Irwig […]
Screening interval, age group and birth cohort
The International Agency for Research in Cancer (1986) reported a summary of the effectiveness, in terms of reduction of risk of invasive cancer, of screening at difference intervals in different age groups (Figure 6.5; IARC 1986). This international study provided evidence that 3-yearly screening, from 20 or 25 to 64 years of age, produced the […]
Organisms seen in cervical cytology
Vaginal microbiology In cytology we are able to visualise a wide range of organisms, and in the case of viruses, we are able to see their cytopathic effects. Physiologically, the vaginal vault contains a mixture of both aerobic and non-aerobic bacteria, most importantly lactobacilli, which helps to maintain an acid environment, usually around pH […]
9a. Terminology and criteria for adequacy
Introduction An agreed terminology for cervical cytology is not only important to ensure consistency of screening and reporting slides but also to enable cytology results to be compared between laboratories, regions and countries, and to be correlated with colposcopy findings, histopathology results and clinical outcome. Among the countries of Europe and to an even greater […]
Importance of quality control on the effect of screening
An additional factor is evident from a closer look at the situation in England, which may well be relevant to other countries. While incidence, mortality and rates of carcinoma in situ were increasing in women below 35 years of age, those were the women from whom 65% of Pap smears were taken at the time […]
Detection of early-stage occult cancers
Detection of occult invasive cancers in asymptomatic women may increase the incidence of cancer in early rounds organised screening. An audit of 382 cancers from 1985 to 1996 in Southampton, during the introduction of organised screening in the background of opportunistic screening with poor quality control, showed a trend from symptomatic to screen-detected cancers with […]
References
Adelstein AM, Husain OA, Spriggs AI. Cancer of the cervix and screening. BMJ 1981;282:564. Arbyn M, Anttila A, Jordan J et al. (Eds). (2008). European guidelines for quality assurance in cervical cancer screening, second edition. Chapter 3 pp.87-88. European Communities 2008. Available as www.screening.iarc.fr/doc/ND7007ENC_002.pdf Albow R, Kitchener H, Gupta N, Desai M (2012). Cervical screening […]
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 […]