SCREENING FOR CERVICAL CANCER

SCREENING FOR CERVICAL CANCER

210 Letters to the Editor SCREENING FOR CERVICAL CANCER SIR,-Dr Skrabanek (June 20, against screening for cervical cancer. His p 1432) contin...

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210

Letters

to

the Editor

SCREENING FOR CERVICAL CANCER

SIR,-Dr Skrabanek (June 20,

against screening for cervical

cancer.

His

p 1432) continues his crusade cancer, this time his target is screening for

idiosyncratic

use

of other

people’s data, to study

however, suggests that he does not expect Lancet readers

the articles he cites in his support. He cites a paper by Laara and us in your May 30 issue as showing that the mortality trends from cervix cancer in Sweden and Norway have been the same. Fig 1 in that paper shows the exact opposite, rates in Sweden falling much more rapidly than those in Norway, especially since 1970. Table n shows that in the age group 40-59 the Swedish rates fell by more than 50% over the period described, in contrast to a fall of less than 10% in Norway. This is the age group where organised screening (as practised in Sweden) as opposed to spontaneous screening should have had an effect, and where the differences between Sweden and Norway are most striking. Skrabanek writes: "The Icelandic data are striking but difficult to interpret. The annual mortality was 11 -7/ 105 in the 15-59 age group in 1955-59, before screening, and 122/105 in 1970-74, a decade after screening started." This represents both a severe distortion of the data and selective quotation. More complete results from Iceland have been published, as quoted by Laara et al, and the annual mortality rates per 105 women in the 25-59 age group in the six 4-year periods 1955-58, 1959-62, 1963-66, 1967-70, 1971-74, and 1975-78 were 16-1,25 4,24-6,26-7,15-0,and 10-2, respectively. Screening was introduced in 1963-66. The picture is clear: mortality was rising before screening started and (with a delay of some five years) began falling rapidly after screening was widespread throughout the community. Since 1978 mortality has fallen further, as can be seen from fig 1 of Laara et al. In stating that "in many countries (eg, Japan, France, Italy) mortality from cervical cancer is much lower than it is in Sweden, and has been falling for the past 20 years at rates similar to the rates seen in Sweden" Skrabanek makes the error of ignoring deaths classified as due to "other malignant neoplasms of the uterus". Many of this latter category would be cancers of the uterine cervix. The age-standardised rates in 1978 (standardised to the European population) for all cancers of the uterus in Sweden, Japan, France, and Italy were 102,11 0,12-3, and 135, respectively. These figures would be much closer to the real mortality rates for cancers of the uterine cervix than the 1978 rates given in the paper cited by Skrabanek of 6-0,4,33,and 11, respectively. The changes in the rates over the period 1956-78 quoted by Skrabanek are meaningless for the same reason, since the classification on death certificates of uterine tumours has changed over time. MRC Biostatistics Unit, 5 Shaftesbury Avenue,

Cambridge CB2 2BW

Susceptibility to measles, mumps, and rubella at different ages. Results

To

are

ensure

sera

elimination of

CRS, selective rubella vaccination of

schoolgirls will be continued until circulation of rubella has ceased. Nokes and Anderson warn of the dangers of dropping selective vaccination prematurely and thus allowing non-immune cohorts of adult women to emerge in the next century. This danger has been anticipated, and as part of the new policy the Public Health Laboratory Service (PHLS) has set up a surveillance system to monitor changes in immunity to rubella in different age-groups. This includes the continued surveillance of rubella antibody prevalence in the antenatal population,3 and the surveillance of measles, mumps, and rubella antibody prevalence across all ages. Preliminary results from about 5000 sera collected in 1986-87 are shown in the figure. These systems and the monitoring of rubella infection in pregnancy3 will indicate whether susceptible cohorts are emerging and, if so, whether they are at risk of infection. In addition, a scheme to provide detailed and rapid information on vaccine uptake in young children has been set Up;4 and after a meeting organised by the PHLS in November, 1986, recommendations on ways of increasing uptake were sent to the JCVI. These recommendations include: increased professional commitment to immunisation, with local monitoring of individual performance; accountability for vaccine uptake at district and regional levels; and adequate funding for local staff and resources. High uptake has been achieved in other countries and in some parts of the UK without recourse to legislation.s If the recommendations are implemented, high uptake could also be achieved throughout the UK. Public Health Laboratory Service, Communicable Disease Surveillance Centre, London NW9 5EQ

CHRISTINE MILLER ELIZABETH MILLER NORMAN BEGG

Preston Public Health Laboratory

N. E. DAY

Royal Infirmary, Preston

Finnish Cancer Registry, Helsinki; and Department of Public Health, University of Tampere

collected in 1986-87.

from about 5000

M. HAKAMA

RUBELLA VACCINATION POLICY: A NOTE OF REASSURANCE

SIR,-A recommendation from the Joint Committee on Vaccination and Immunisation (JCVI) to augment the current selective rubella vaccination policy was given ministerial approval in April, 1987.1 As Mr Nokes and Professor Anderson indicate (June 20, p 1441), the decision was made on epidemiological evidence that rubella infection in pregnancy-and thus congenital rubella syndrome (CRS)—continues to occur at an unacceptable level despite the high proportion of women (97%) who are now immuneUnder the new policy, the measles vaccine currently given to young children will be replaced by a combined measles/ mumps/rubella vaccine with the objective of eliminating these three diseases. A high vaccine uptake in those aged 1-2 years is essential.

P. MORGAN-CAPNER

1. Smith T. Measles and the government. Br Med J 1987; 294: 989-90. 2 Miller CL, Miller E. Rubella vaccination in the UK: Time for a complete strategy

Lancet 1985; ii: 732. CL, Miller E, Waight PA. Rubella susceptibility and the continuing nsk of infection in pregnancy. Br Med J 1987; 294: 1277-78. 4. Gill ON, Begg N. Public Health Laboratory Service, Communicable Disease Surveillance Centre. Communicable Disease Report 87/12: 3-6. 5. Walker D, Carter H, Jones I. Measles, mumps, and rubella: the need for a change of policy. Br Med J 1986; 292: 1501-02.

3. Miller

SPLENECTOMY IN HODGKIN’S DISEASE AND SECOND LEUKAEMIAS

SIR,-Staging laparotomy with splenectomy, though a generally accepted procedure in the management of Hodgkin’s disease, has been on the decline lately. The major complication of splenectomy has been on increased risk of infection.1,2 We report here an unexpected association between splenectomy and the risk of second leukaemia.