Two developments in the screening of cervical cancer are set to revolutionise the UK's programme, according to doctors.
Trials of the first commercially available DNA test for cervical cancer are to be carried out in Britain on 12,000 women. This extensive study is one of the largest screening trials in the UK. And the first computerised system to measure the quality of a screener's technique has been launched.
The DNA test, made by the Digene Corporation, detects the presence of high-risk types of human papilloma virus, which has been implicated as a cause of cervical cancer. The trials are to be conducted by the Imperial Cancer Research Fund. Professor Jack Cuzick, the ICRF's head of mathematics, statistics and epidemiology, said:
'This new test is a good candidate to reduce costs and improve performance.'
The two-year study aims to demonstrate that the test is a more effective way of detecting cervical neoplasia (abnormal cell growth) than the Pap smear, and may lead to considerable cost savings to the NHS by increasing the interval between smears.
The HPV/DNA test is a molecular diagnostic assay that differentiates between high- or medium- risk types of HPV and low-risk types. The test detects HPV in over 90 per cent of women where high-grade lesions are present, compared with 70-75 per cent with the Pap smear. Like the Pap smear, the HPV/DNA test is performed on a sample of cervical cells taken during a pelvic examination. A Pap smear and HPV/DNA test can be performed from the same sample using liquid cytology.
Meanwhile, Bayer plc has launched a new computerised system called Pathfinder, which it claims can be integrated into any cytology laboratory for a fraction of the budget an average trust spends on stationery and can substantially reduce the risk of screener error.
Pathfinder works by mapping screener progress across each slide - compiling performance information, including total slide coverage. This information is displayed on a monitor enabling screeners to quickly check they are achieving the screening standards recommended to identify suspicious cells.
Pathfinder costs£6,000 and several can be linked to provide a screening unit.