Court shows experts split on screening

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The Independent Online
A HIGH COURT case that ends today has revealed a disturbing split between medical experts over how effectively they can spot a virulent form of cervical cancer. Their disagreement will further shake confidence in the cervical screening programme, which has been hit by several scares in recent years.

Judge Peppitt QC is to rule on the case of three women from Kent who claim they have cancers as a result of misdiagnosed smear tests by the Kent and Canterbury Hospital, centre of the worst cervical screening scandal, in which eight women are believed to have died and 30 needed hysterectomies because of failures.

Helen Palmer, 35 of Whitstable, Sandra Penney, 35 of Ramsgate, and Lesley Cannon, 38, from Sheppey say the hospital screeners misread their tests, and as a result they contracted adenocarcinoma, the less common form of cervical cancer that affects mainly younger women. All three needed radical hysterectomies.

Much of the dispute in the 10-day court case centred on whether cyto- screeners, the laboratory technicians who examine slides, should have been able to notice the pre-cancerous signs when the smears were taken between 1990 and 1992. The medical science of analysing such slides is said to have improved since the early 1990s.

But, alarmingly, the experts in the case disagreed over what the women's four smears showed. In one case they were starkly divided on whether a 1990 smear showed signs of adenocarcinoma at all. Of four cyto-pathologists who examined the slide, two said there was clear evidence of pre- cancer and two said there was no such evidence.

The two medical experts who were retained by the women said the smear shows serious and readily visible abnormalities. Professor Roger Cotton, 72, the retired head of cytology at Nottingham University Hospital, said "significant glandular abnormalities are present ... In my opinion this delay of five and half years (until diagnosis of cancer) is inexcusable."

Professor Thomas Krauz, 51, a consultant at Hammersmith Hospital, agreed with Professor Cotton. "This is not a negative smear as stated in the original," he said. Professor Krauz had several of his cyto-screeners at Hammersmith blind-test the slide. All four identified problems.

But the two experts advising the East Kent Health Authority, on behalf of the hospital, voiced the opposite opinion. Dr Andrew Boon, 40, consultant of St James' University Hospital, Leeds, said: "Even in retrospect, I cannot find any convincingly dyskaryotic cells within the smear and all the changes present could be reasonably attributed to florid inflammation."

Dr David Hughes, 35, consultant at Chesterfield Hospital, said: "I agree with Dr Boon that the 1990 smear is acceptable as negative."

Judge Peppitt was clearly disturbed by the conflict over the slides and came back to it a number of times during the hearings. The consultants were cross-examined about their evidence. Such disagreement will raise concern over the effectiveness of cervical screening programmes.

Adenocarcinoma accounts for 10 to 15 per cent of cervical cancers but the proportion is growing. Its diagnosis and treatment is fraught with difficulty. Experts say that cells indicative of adenocarcinoma on the smear are the most difficult to interpret.

The National Cervical Screening Service said that even with regular smears every three to five years, only 50 per cent of adenocarcinomas will be prevented, compared with 80 to 90 per cent of invasive squamous cell cervical cancers, the commonest sort.

Julietta Patnick, national co-ordinator of the screening service, said: "The evidence from around the world shows the cervical smear test is not a reliable test for picking up and preventing adenocarcinoma."

To demonstrate medical negligence, the victim mustprove the standard of care was below that of a reasonably competent practitioner at the time. Kent and Canterbury Hospital NHS Trust has denied this.

The trust has already admitted the screening department was poorly run and the screeners inadequately trained. It has settled 45 cases but refused compensation to women in other cases.