Grading of cervical intraepithelial neoplasia

SIR,-The main arguments of the article by Dr Sezgin M Ismail and colleagues' are based on two questionable assumptions: the accepted value of grading cervical intraepithelial neoplasia and the policy of treating women with all grades. The terminology of cervical intraepithelial neoplasia regards the potentially premalignant epithelial disorders of the cervix as a continuous range of disease, and this is a concept that it theoretically irreconcilable with subdivisions. Grading was introduced for classification (the annual cervical cytology return requires data on the number of cases of cervical intraepithelial neoplasia grade III, for example) and for selecting patients for treatment, but it has always been acknowledged that grading is arbitrary and subjective. Secondly, Dr Ismail and colleagues assume that it is current practice to treat women with all grades of cervical intraepithelial neoplasia, citing the report of the ninth study group of the Royal College of Obstetricians and Gynaecologists. This study took place in 1981 and, although its recommendations were authoritative at the time, they do not necessarily apply eight years later. There has been intense discussion recently about the treatment of minor abnormalities, and it is now common practice for women with lesions no worse than cervical intraepithelial neoplasia grade 1 to be followed up rather than treated, although, inevitably, different policies are adopted in different departments. The lack of agreement by histopathologists is largely owing to the imprecision of the currently available criteria for diagnosis; perhaps if Dr Ismail and colleagues had used slightly modified criteria2 their results may have been different. It is a mistake to place too much emphasis on the proportion of the thickness of the epithelium showing differentiation and too little emphasis on nuclear abnormalities. ' Unfortunately, nuclear detail is not shown well with formol saline fixation, and Bouin's fluid is strongly recommended for fixing cervical biopsies. Histopathologists and colposcopists certainly need to be aware of the difficulties in diagnosis, particularly at the bottom of the range, as wvell as the overlap with benign conditions, but it is my belief that these problems are already widely appreciated. I agree with Dr Ismail and colleagues that the epithelial abnormalities of the cervix may be divided into only two categories: those that require treatment and those that do not and can be followed up. This pragmatic approach still requires a dividing line to be defined within the range of cervical intraepithelial neoplasia, so the issue cannot be entirely avoided. It must also be borne in mind that the decision whether to treat a woman with an abnormal result on smear testing depends on several other factors, including the result of the test and the distribution of the lesion, in addition to the result of the colposcopic biopsy. Furthermore, the biopsy specimen does not necessarily always reflect the most severe lesion on the cervix. The most effective saving of resources will be made by referring women with mildly abnormal smears for colposcopy only if the changes persist. Once a woman has been seen in the colposcopy clinic and a biopsy specimen taken further follow up by colposcopy and cytology may well be as costly as immediate treatment and will certainly be more so if treatment is eventually needed.