The NHS Cervical Screening Programme (NHSCP) was introduced in 1988. As a result of this programme, the incidence of cervical cancer fell from 18.4 in 1988 to 8.8 in 2005. Cervical screening aims to prevent cervical cancer by identifying abnormal cell changes, allowing for the treatment of precancerous conditions. Cervical screening can also detect cervical cancer in women who have progressed to this stage.
In this study, the researchers examined data that was collected in Southampton and South West Hampshire. The authors identified 382 women who had been diagnosed with invasive cervical cancer between 1985 and 1996. The study compared screen-detected cancers with symptomatic cancers over time.
Cancers were categorized as ‘screen detected’ if the cancer was found as a direct result of an abnormal smear reported during the routine screening test while a woman was asymptomatic. ‘Symptomatic’ cancers were detected when a woman complained of symptoms.
The authors found that during this period, the proportion of symptomatic cancers fell significantly, while the proportion of screen-detected cancers increased. Cancers detected through screening were more likely to be stage 1 than symptomatic cancers, and were associated with a better 5-year-survival.
Despite the increase in screen-detected cancers the overall cancer rates were significantly lower in screened women because of treatment of precancerous conditions.
The authors stress that cancers were increasingly detected in young women and were seldom found on the first cytology test. These findings may present an argument against delaying the first screening invitation to the age of 25 years.
Lead author, Dr. Amanda Herbert, from the Department of Histopathology at St Thomas’ Hospital, said “Cancers in women screened within five years were more likely to be screen-detected, early stage cancers in younger age groups. The reasons for cancers developing in women who had previously been screened included false negative cytology, inappropriate management of low-grade cytology, delayed referral for colposcopy and incomplete treatment of high-grade cervical intraepithelial neoplasia (CIN).
“The audit justifies the major improvements in quality control implemented during the 1990s. It shows the importance of regular screening, especially in young women in whom most cases of high-grade CIN are successfully treated and in whom early screen-detected cancers are more likely to be found.”
Prof. Philip Steer, BJOG editor-in-chief, said “This study demonstrates that in addition to lowering overall cancer rates, cervical screening can also help to detect cervical cancer at an earlier stage, leading to better outcomes.
“Cervical cancer screening remains an important way to prevent cervical cancer. All women eligible for cervical screening are strongly encouraged to attend routine cervical screening.”
Ends
Notes
BJOG: An International Journal of Obstetrics and Gynaecology is owned by the Royal College of Obstetricians and Gynaecologists (RCOG) but is editorially independent and published monthly by Wiley-Blackwell. The journal features original, peer-reviewed, high-quality medical research in all areas of obstetrics and gynaecology worldwide. Please quote ‘BJOG' or ‘BJOG: An International Journal of Obstetrics and Gynaecology' when referring to the journal and include the website: www.bjog.org as a hidden link online.
For more information, please contact the RCOG press office on 020 7772 6446 or 020 7772 6357.
Evidence shows that regular screening in young women ensures that most cases of high-grade CIN are successfully diagnosed and treated. See Herbert A, Smith JAE. Cervical intraepithelial neoplasia grade III (CIN III) and invasive cervical carcinoma: the yawning gap revisited and the treatment of risk. Cytopathology 1999;10:161-70.
Reference
Herbert A, Anshu, Gregory M, Gupta S, Singh N. Screen-detected invasive cervical carcinoma and its clinical significance during the introduction of organized screening. BJOG 2008; DOI: 10.1111/j.1471-0528.01989.x.
