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 […]
The columnar epithelium of the endocervix
The epithelium that lines the endocervical canal and endocervical crypts consists of a single layer of mucus-producing columnar cells. These cells are tall and cylindrical and are arranged in a picket fence formation. The nuclei are mostly situated basally, adjacent to the basement membrane, but during active mucous secretion the nucleus can be displaced by […]
Adenocarcinoma and adenocarcinoma in situ
Adenocarcinoma Adenocarcinoma of the cervix is a malignant neoplasm that involves the glandular epithelium of the cervix. There are several types of adenocarcinoma, most of which have similar aetiology and risk factors to squamous cell carcinoma. Endocervical-type mucinous adenocarcinomas comprise 70% of adenocarcinomas (WHO). HPV types commonly associated with adenocarcinoma are 16, 18 and 45 […]
Metaplastic change in the cervix and its physiological basis
Metaplasia is the name given to the process by which one fully differentiated type of epithelium appears to transform into another differentiated type. It is usually an adaptive change that occurs in in reaction to chronic irritation, or in response to hormonal stimuli. As the female goes through puberty and reaches maturation, hormonal changes cause […]
Clinical presentation, stages and treatment of cervical cancer
The clinical presentation and pattern of growth of invasive cervical cancer is variable. The tumour may be polypoid, papillomatous or fungating, or it may be flat or ulcerating (Figure 4.7). Initially, like most cancers, there is local spread or growth; it travels upward into the body of the uterus, downward into the vagina or laterally into the pelvic folds. Eventually the […]
5. The principles of screening and measurement of accuracy
Principles of screening With reservations predicted by the authors at the time, cytological cervical screening has to a major extent fulfilled the criteria defined by Wilson & Jungner (1968) (Figure 5.1). These principles have been revisited more recently by Andermann et al. (2008) in the knowledge of high-risk HPV being a necessary cause of cervical […]
References
Andrae B, Andersson T M-L, Lambert PC et al. (2012). Screening and cervical cancer cures: population based cohort study. BMJ e900. Doi: 10.1136/bmj.e900. Austin RM, Zhao C (2012). Type 1 and type 2 cervical adenocarcinomas: some cervical cancers are more difficult to prevent with screening. Cytopathology 23:6-12. Bansal N, Wright JD, Cohen CJ, Herzog TJ […]
Squamous epithelium
Squamous epithelium of the cervix and vagina is non-keratinising and is composed of a continuous layer of stratified (multi-layered) flat, polygonal cells with centrally located nuclei. The stratified squamous epithelium of the cervix can be divided into three layers: the superficial, intermediate and parabasal/basal layer. Stratified squamous epithelium has a mainly protective function but also […]