The cause of cervical cancer in unknown. Research has concentrated on a sexually transmitted causative agent. Specific high risk human papilloma virus (HPV) types 16, 18, 31, 33 and 35 has been linked to CIN and invasive cervical cancer and may have a causative role. Risk factors identified include age, sexual activity, parity, smoking, socio-economic status and use of oral co ntraceptives. The strongest risk factor for cervical cancer relates to sexual behaviour. Early age at first intercourse, the more sexual partners a woman has and the more sexual contacts a woman's male partner has the higher the risk for a woman.
Cervical cancer develops from abnormal epithelial changes in the transformation zone. Cells superficial to the epithelial basement membrane may undergo neoplastic change. Dyskaryosis is the nuclear change seen in lesions histologically described as cervical intraepithelial neoplasia (CIN).
When neoplastic changes are found to extend deep into the epithelial basement membrane invasive carcinoma is diagnosed. Generally, women with borderline smear results on two or three occasions, mild dyskaryosis on two occ a sions and moderate or severe dyskaryosis on one occasion require colposcopic assessment.
The five year relative survival rate for stage 1 invasive cervical cancer is 79% reducing to 7% for stage IV. The frequent absence of symptoms in early cervical c ancer and this marked difference in survival rate for the different stages of invasive cervical cancer are the raison d'etre for the cervical screening programme. By detecting the disease at an early stage prognosis can be improved by earlier treatment.
The Health of the Nation target for cervical screening is to "reduce the incidence of invasive cancer by at least 20% by the year 2000 - from 15 per 100,000 women in 1986 to no more than 12 per 100,000 women by the year 2000".
Evidence suggests that a 6 5 to 70% reduction in mortality is possible in the long term is overall coverage * of 80% can be achieved. In 1994/5 the coverage of eligible women was 85.7%. In 1994, 1369 women died from cervical cancer in England and Wales making it the eighth most common cancer in the UK. The death rate - 63 per million, increases with age to reach a peak in the oldest age group. In 1991 there were 3,768 new cases of invasive cervical cancer in England and Wales. Tables A and B show the incidence and incidence rates of cervical cancer in females aged 20-64 for 1986-1990 by locality patch for West Sussex.
During April 1997-98 there were 8 new referrals for colposcopic assessment as a result of smear abnormalities detected at screening at Cuckfield Medical Practice. During the same period there was one recorded case of invasive cervical cancer. *This is the percentage of women in the target group (20-64) who have been screened in the past 5 years.
Cancer Research Campaign [CRC] (1994) Cancer of the cervix Uteri Factsheet 12 London CRC
Department of Health (1992) The Health of the Nation. A Strategy for Health in England London HMSO
NHSCSP (1996) Cervical Screening: A Pocket Guide NHSCSP Publications
Schiffman, M H, Bauer, HM, Hoover, RN et al. (1993) Epidemiological evidence showing that human papillomavirus infection causes most intraepithelial neoplasia Journal Natl. Cancer Inst. 85, 958-964
Wolfendale, M R (1995) Taking Cervical Smears London, British Society for Clinical Cytology
Cervical Cancer Screening
Cervical cancer screening began in the United Kingdom (UK) in the sixties but was ineffective because of problems with organisa tion, accountability and commitment. Younger women were screened opportunistically when attending for ante-natal or contraception services and therefore more frequently. Before 1988 at least two thirds of women with invasive cancer and 90% of women ove r the age of 40 had never been screened. Only in north east Scotland, where a case-control study of the cervical screening programme based on the central pathology laboratory in Aberdeen had been set up, was a reduction in incidence seen. In 1987 a report of the Intercollegiate Working Party recommended three yearly cervical cancer screening and to ensure that population screening covered those with the highest incidence of the disease (namely older women of low socio-economic status).
The setting up of national computerised call/recall system and a National Health Service Cervical Screening Programme National Co-ordinating Network in 1988 and the setting of target payments for cervical screening in the 1990 General Practitioner Contract have influence d improvements in organisation, service provision and an increase in screening activity and population coverage. Since 1991 mortality has fallen dramatically.
Cervical cancer screening is aimed to protect against squamous cell carcinoma. It is unique in identifying disease at a premalignant stage when treatment effectively prevents the development of invasive disease. It is advised for women who are, or ever have been sexually active. Women between the ages of 20 and 64 are invited to have a cervical smear test at least once very five years as per current Department of Health guidelines. Forty six per cent of Health Authorities screen eligible women five yearly and thirty nine per cent three yearly. West Sussex Health Authority policy recom m ends three yearly screening for women aged 20-34 and five yearly screening for women aged 35-64.
Assuming 100% coverage of the population, screening women aged 20-34 every 5 years, every 3 years or yearly would be expected to reduce the incidence of ce rvical cancer by 84%, 91% or 93% compared with an unscreened population. This would involve 9, 15 and 45 smear tests in a lifetime respectively. There is no justification for including teenagers in the National Health Service Cervical Screening Programme (NHSCSP). In 1996 there were no deaths from cervical cancer in England and Wales in teenagers.
It is recommended that calls should be initiated after a woman's twentieth birthday and before her twenty fifth birthday.
The number of women aged 20-65 registered at Cuckfield Medical Practice as at April 1998 = 1846
The setting of target payments for cervical screening has resulted in 87% of practices reaching the higher 80% target level in 1994/5 compared with 53% in April 1990.
Full payment for smears taken is made if 80% of the target population (all eligible women between the ages of 25-65 in England and Wales, 20-60 in Scotland) have received an adequate smear in the previous 5.5 years: part payment (33% of the full amount) being made if 50% of the target population have received an adequate smear in the previous 5.5 years.
Cuckfield Medical Practice achieves the higher target level which, at 1 April 1998, was 87.61%.
Total number of women in age range 25-64 = 1592
Women who were not eligible for screening (eg had a complete hysterectomy) = 155
Women who were eligible = 1437
Women adequately tested in the last 66 months = 1259
Women who were eligible who had not been adequately tested in the last 66 months = 178
Of these 178 women
18% were from the 25-30 age group,
11% from the 31-35 and 56-60 age groups,
10% from the 46-50 and 51-55 age groups,
12% from the 61-65 age group and
14% from the 36-40 and 41-45 age groups.
Providing detailed, accurate information in a sensitive manner before taking a smear, explaining the procedure and its purpose clearly, can reduce women's anxiety.
Complete visualisation of the cervix
Ensuring the whole of the transformation zone is sampled. Research supports the use of Aylesbury or similar extended tip sampler.
As per quality assurance guidelines more than 80% of smears should show cytological evidence of transformation zone sampling - endocervical cells, immature metaplastic squamous cells and cervical mucus.
No opportunity should be missed to promote the NHSCSP. Women overdue for a smear should be offered cervical screening on an opportunistic basis or encouraged to attend for a smear test at a later date during consultations with GP, Practice Nurse, Health Visitor and when attending, for example, family planning sessions, new patient health checks, hypertension and asthma follow up.
Contact non attenders/responders by letter and/or telephone check on reasons for non acceptance of screening
Flag computer records of women overdue for smear test
Display posters and leaflets to encourage non attenders and first attenders for a smear to come forward
Appropriate training and three yearly updates for all health care professionals taking smears
Minimum length of consultation for a first smear 30 minutes otherwise 20 minutes
Follow NHSCSP guidelines on not screening women under 20 and on avoiding unscheduled smear taking (eg before six months postnatally)
Improve the experience of women by ensuring privacy and better smear taking technique and communication skills
Austoker, J (1994) Cancer Prevention in Primary Care British Medical Journal 309, 241-8
Cancer Research Campaign [CRC] (1994) Cervical Screening. Factsheet 13 London, CRC
Day, N E (1989) Screening for Cancer of the Cervix. Journal of Epidemiology and Community Health, 43 103-106
Dey, P Collins, S Desai, M Woodman, C (1996) Adequacy of cervical sampling with the cervex brush and the Aylesbury spatula: a population based randomised controlled trial British Medical Journal 313, 721-723
NHSCSP (1996) Cervical Screening: a Pocket Guide NHSCSP Publications NHSCSP (1997) Guidelines for Clinical Practice and Programme Management NHSCSP Publication No. 8, December 1997
Sasieni, P (1996) Cervical sampling devices: Extended tip spatulas (such as Aylesbury) should replace the Ayre British Medical Journal 313, 1275-1276
Wolfendale, M R Howe-Guest, R, Usherwood, M McD, Draper, G J (1987) Controlled trial of a new cervical spatula. British Medical Journal 294, 33-35
Wolfendale, M R (1995) Taking Cervical Smears London, British Society for Clinical Cytology