4 AUGUST 1967, Page 23

Women at risk

Sir: May I be permitted to congratulate Dr Rowan Wilson on his scholarly appraisal of the use of cytology, jn his essay 'Women at risk' (28 July)? As he states. one cancer-prevention test in 200 is positive but it is important that this average figure does not fit special groups such as those obtained from screening a vo clinic. These patients are often teenagers, yet the test for cancer-like cells from the neck of the womb is positive in 2 per cent. suggesting that the age at which copulation commences has a direct bearing on the develop- ment of pre-cancer. Thus doctors taking part in screening 'normal' patients ignore the fact that :he NHS will pay them a (small) fee if tests are taken from women over thirty-five. (No one in this field is clear why the age thirty-five was chosen, but perhaps their Lordships at the Treasury know.) Ail women with married or equivalent status are at risk.

In 1965 the Ministry of Health established five .schools to train the cyto-technicians who screen tests at the microscope, so that in time the rela- lively few tests carried out in the mc should rise to numbers when the full impact of this prophy- lactic method may be read in the fall in the number of deaths from cancer. Meantime, more tests are done in British Columbia than in Britain; one and a half million in the Pacific; fifty-plus million in the UK.

The scourge of lung cancer, which most authorities link with cigarette smoking, is also under attack by the same technique, but the 'cells' are more difficult to obtain and, once found, their source is difficult to localise. Nevertheless, the 'cough-test' may prove to be an amber light for the thirty-fags-a-day addict.

The target in the cytology test in the wombs and in the lungs, then, is the same: namely, the recognition of curable 'pre disease long before the dangerous invasive stage of cancer develops. For 'women at risk' cytology is a big step forward.