After a series of "scandals" involving allegedly misdiagnosed cancers, Dr Milena Lesna, consultant pathologist at the Royal Bournemouth Hospital, Dorset, says pathologists are being made into scapegoats and it is time that hospital managers and the public were told zero error is impossible.
In one year, 1995, 19 pathologists were suspended for alleged incompetence, but in 16 of the cases the allegations were proved unjustified at subsequent tribunals. However, only five of the pathologists have been reinstated. "Not guilty is not the same as innocent," Dr Lesna says in an article in the Journal of Clinical Pathology.
Investigations are often triggered by personality clashes or hostility within a department. Female doctors were much less likely than men to get their jobs back, although they were more often found not guilty of any misdoing.
Bernard Charnley, consultant pathologist at the Prince Charles Hospital, Merthyr Tydfil, has been suspended on full pay of pounds 60,000 a year for four years, and it could take another year before the issue is resolved. By that time, the total cost to the National Health Service, including legal charges, could be more than pounds 500,000.
Dr Charnley's problems began while he was on paternity leave when a complaint was made that he had inaccurately reported the results of cervical screening tests, an allegation he has consistently denied.
Colleagues say that the performance for the cytology service at the South Wales hospital was within national guidelines and above average. One said: "The tragedy is that he was performing well and is very conscientious and he is being pilloried when there are many people around the country with far worse figures who are still in post. It is very unfair."
A report on the case is due in the next couple of months from an independent panel of experts, which is currently sifting through the evidence. Depending on the result, there could be an appeal to the Secretary of State for Wales, which could take another year.
The Royal College of Pathologists has not defined what error rate should be regarded as reasonable, making it difficult for pathologists to know where they stand. One study of 200 pathologists found that only one quarter claimed to have made no error in the previous five years. Diagnostic work is a team effort and pathologists rely on other doctors to supply a correctly taken tissue sample, backed by good clinical information, to make the diagnosis.
The royal college and the General Medical Council have set up a peer review system to adjudicate on alleged errors but that is not enough, Dr Lesnastates in her article. "Pathologists need to explain to the public that all diagnostic and screening errors carry a certain rate of error, and that accusations of professional incompetence only end up demoralising experienced staff who are often difficult to replace."
Professor Ian Lauder, vice-president of the Royal College, said the number of pathologists whose work had been identified as sub-standard was disproportionate compared with other specialties. Most doctors buried their mistakes but the material that pathologists work with - tissue samples, cervical smears - remain on file for ever.
"People will be able to come back in 100 years and see what mistakes I made," he said.
Professor Lauder said the college had been trying for some years to set up a study to assess what would be an acceptable error rate for pathologists but had been unable to raise the necessary funds.