Regular audit of colposcopic biopsies from women with a mildly dyskaryotic or borderline cervical smear results in fewer cases of CINIII

Two years after introducing mandatory review of cases in which the cervical smear was discrepant with subsequent colposcopic or histological finding, the predictive accuracy of a first abnormal smear and the need for treatment were analysed. The results were compared with performance figures prior to this form of audit policy. Over 12 months 415 women referred for colposcopy were studied. Three per cent of patients with a single borderline smear and 6% with mild dyskaryosis had cervical intraepithelial neoplasia grade III (CINIII) revealed in histopathological examinations after colposcopy. Only 25% with a borderline smear and 33% with mild dyskaryosis required treatment. Of women with moderate dyskaryosis, 18% had a biopsy showing CINIII and 46% were treated. Of women with severe dyskaryosis in their cervical smear, 61% were shown to have CINIII or invasive cancer on biopsy and 90% were treated. Regular audit improved cytological prediction of grade of epithelial abnormality found on biopsy, allowing accurate, safe surveillance for minor smear abnormalities.     

Regular audit of colposcopic biopsies from women with a mildly dyskaryotic or borderline cervical smear results in fewer cases of CINIII

Two years after introducing mandatory review of cases in which the cervical smear was discrepant with subsequent colposcopic or histological finding, the predictive accuracy of a first abnormal smear and the need for treatment were analysed. The results were compared with performance figures prior to this form of audit policy. Over 12 months 415 women referred for colposcopy were studied. Three per cent of patients with a single borderline smear and 6% with mild dyskaryosis had cervical intraepithelial neoplasia grade III (CINIII) revealed in histopathological examinations after colposcopy. Only 25% with a borderline smear and 33% with mild dyskaryosis required treatment. Of women with moderate dyskaryosis, 18% had a biopsy showing CINIII and 46% were treated. Of women with severe dyskaryosis in their cervical smear, 61% were shown to have CINIII or invasive cancer on biopsy and 90% were treated. Regular audit improved cytological prediction of grade of epithelial abnormality found on biopsy, allowing accurate, safe surveillance for minor smear abnormalities.     

Invasive cancer of the cervix in women with mild dyskaryosis followed up cytologically.

Mildly dyskaryotic smears are common, and women with such results are often followed up with further cervical smear tests. An important consideration in evaluating this practice would be the annual incidence of invasive cervical cancer. A reanalysis of five previous studies of the cytological follow up of women with mildly abnormal smear test results was undertaken to calculate this incidence. The annual incidence of invasive cancer in these women ranged from 0 to 420 per 100,000 women years. The large studies providing the most precise estimates had annual rates of 143 to 420 per 100,000 women years. This is 16 to 47 times greater than in women aged 15-34 years in England and Wales. The average rate was 208 per 100,000 women years. Women with mild dyskaryosis are at high risk of developing invasive cervical cancer despite cytological follow up. A full appraisal of the costs and benefits of colposcopy in this situation is urgently required.     

Mild and moderate dyskaryosis: can women be selected for colposcopy on the basis of social criteria?

OBJECTIVE--To describe the distribution of cervical intraepithelial neoplasia grades among women with mild and moderate dyskaryosis after a single cervical smear and to determine whether social criteria could help identify women who are at increased risk of grade II or III disease. DESIGN--Cross sectional analysis within a randomised prospective study. Subjects had a repeat smear, a colposcopic examination, and an excision biopsy of the transformation zone. In addition, women were asked to complete a social questionnaire. SETTING--Colposcopy clinic, Aberdeen. SUBJECTS--228 women with a single smear test showing mild or moderate dyskaryosis. MAIN OUTCOME MEASURES--Histology, age, sexual and contraceptive history, cigarette smoking. RESULTS--159 (70%) women had cervical intraepithelial neoplasia grades II or III. Among current smokers the prevalence of grade II and III disease was higher in women who smoked greater than or equal to 20 cigarettes a day (84%) than among those who smoked less (66%; p less than 0.04). Women with more than one sexual partner also had a higher prevalence (75%) than women with only one partner (50%; p = 0.0028). Use of oral contraceptives and younger age were not significantly associated. The prevalence of grade II or III disease was up to 66% in the lower risk groups. CONCLUSIONS--Because of the high prevalence of cervical intraepithelial neoplasia grades II and III in both the high and the low risk groups social factors are not useful for selecting women with mild or moderate dyskaryosis for either early referral to colposcopy or cytological surveillance.     

Risk of cervical cancer associated with mild dyskaryosis.

In a survey of 1781 patients who had mild dyskaryosis in a cervical smear taken between 1965 and 1984 invasive cancer occurred in 10 women. In four cancer was diagnosed soon after presentation, and in three it developed some years after default from follow up. Invasion occurred in one patient during cytological surveillance and in a further two after referral for colposcopic supervision. A poor correlation was found between a single cervical smear showing mild dyskaryosis and biopsy results. This was, however, improved by a series of smears. During initial surveillance cervical smear results reverted to normal in 46% of our patients within two years. During longer term follow up none of these patients developed invasive cancer, and life table analysis showed that three quarters had not relapsed after 14 years. We also found no evidence to suggest that preinvasive disease is more rapidly progressive in younger women. Our results indicate that cytological surveillance is acceptably safe provided that biopsy is advised if dyskaryosis persists.     

O‐110 YEAR AUDIT OF GLANDULAR CYTOLOGY REPORTS WITH SPECIAL REGARD TO THE EFFECT OF CONVERSION TO LBC

Objectives: A randomised trial in screening to improve cytology (ARTISTIC Trial) was set up to evaluate the effectiveness of human papilloma virus (HPV) testing in primary cervical screening. Design: Women attending the NHS Cervical Screening Programme in Greater Manchester were screened for HPV in addition to routine cytological testing with ThinPrep Liquid‐Based Cytology (LBC). 25 020 women aged 20–64 were screened at entry and 3 years later. Participants were randomised in a 3 : 1 ratio between those whose HPV test result was revealed and acted upon and those in whom it was concealed. Results: A total of 24 510 women (18 386 revealed and 6124 concealed) had adequate cytology and HPV results. Cytology results at entry were: 87% normal, 11% borderline or mild, 1.1% moderate and 0.6% severe dyskaryosis or worse. Prevalence of HPV decreased sharply with age, from 40% at age 20–24 to 12% at 35–39 and 7% or less above age 50, and increased with cytological grade, from 10% (normal cytology) to 31% (borderline), 70% (mild), 86% (moderate), and 96% (severe or worse). Only 60% of women with severe dyskaryosis showed HPV 16 and / or 18 infection. Conclusion: The ARTISTIC Trial has provided the largest collection of LBC samples with HPV typing in Greater Manchester population. It has shown that the HPV testing is practicable in routine screening in women aged over 30. HPV 16 and 18 are more predictive for underlying disease, but other HPV types account for 30% of high‐grade disease.     

Six years' audit of laboratory workload and rates of referral for colposcopy in a cervical screening programme in three districts.

OBJECTIVE--To determine laboratory workload and rates of referral for colposcopy in a three district cervical screening programme during 1983-9 to assess the feasibility of accommodating call up of all women at risk, recall at three year intervals (now five year intervals), and investigation of women with all degrees of abnormality. DESIGN--Analysis of computerised screening histories dating back to 1977 of women screened in the Avon cervical screening programme. SETTING--Three district health authorities covering the population of Bristol and Weston-super-Mare, comprising 800,000 people, of whom 250,000 were female residents aged 20 to 64. SUBJECTS--196,977 Women aged 20 to 64 screened in cervical screening programme since 1983. RESULTS--Laboratory workload devoted to follow up of women with abnormalities increased sharply between 1987-8 and 1988-9, with increases of 54% (from 2075 to 3196) in the number of smears for follow up of severe dyskaryosis and invasive cancer, 40% (from 1925 to 2695) for mild and moderate dyskaryosis, and 49% (from 1793 to 2677) for borderline change. The increases were partly explained by the introduction in April 1988 of protocols for follow up and investigation based on guidance in an intercollegiate working party report. The proportion of women with mild and moderate dyskaryosis who were recommended for referral for colposcopy increased steadily from 9.9% in 1983-4 to 79.9% in 1988-9, and for borderline change the proportions were 3.5% and 13.6% respectively. Of all women tested in 1988-9, referral for colposcopy was recommended in 3%. CONCLUSIONS--The increase in laboratory follow up work identified, if it continued, could result in half of existing laboratory capacity in Avon being devoted to follow up work by 1993, with little prospect of maintaining call, recall, and quality control. Investigation of all women with minor cytological abnormalities is neither justifiable nor sustainable and will undermine the benefits of screening by increasing the rate of false positive results and the financial costs.     

Management of Women With A Cervical Smear Showing A Mild Degree of Dyskaryosis: A Review of Policy

Three hundred and thirty-seven women who presented for the first time with a cervical smear showing a mild degree of dyskaryosis were followed for a minimum period of 3 years and 9 months. Of the 305 women with complete cytological and histological records, 178 were biopsied and 127 remained on cytological follow up. In the biopsied group one case of microinvasive squamous cell carcinoma was diagnosed within 1 year of the patient's first abnormal smear. A further 24% showed cervical intraepithelial neoplasia (CIN) I, 17% showed CIN II and 29% showed CIN III. The overall regression rate for the group of 305 women was 34%. Our results indicate that cytological surveillance is acceptable provided that biopsy is advised when dyskaryosis persists. No major modifications to laboratory policy are indicated and in approximately 34% of cases an unnecessary hospital referral would be avoided.     

The Cytological Prediction of Cervical Intraepithelial Neoplasia In Colposcopically Directed Biopsies

The tissue sections and preceding cervical smears of 1262 women who had colposcopic cervical biopsies were reviewed and the reports correlated. Close correlation between the cytological and histological findings, to within one histological grade of cervical intraepithelial neoplasia (CIN), was noted in 86% of cases. However, the biopsy was negative, or contained evidence of wart virus infection only, in 24% of cases where dyskaryotic cells had been observed in the cervical smear. Of particular concern was the fact that negative histological findings were recorded in 13% of cases where the smear contained cells showing a moderate dyskaryosis and in 1.26% of cases where the smear showed severe dyskaryosis. This suggests that colposcopically directed biopsies do not always reflect the underlying pathological changes in the cervix. Management of these cases is discussed. In 45 women with a normal cervical smear prior to biopsy, histology revealed seven cases of CIN 3 and one case of invasive squamous carcinoma. This indicates that referral for colposcopy is advisable whenever there is clinical suspicion of cancer, even if the cervical smear report is normal.     

Outcome analysis of 4 years' follow-up of patients referred for colposcopy with one smear showing mild dyskaryosis

Objective: To assess the 4‐year outcome of patients after one smear showing mild dyskaryosis with respect to smear regression rate, prevalence of cervical intraepithelial neoplasia (CIN) and the effect of age. Methods: Retrospective analysis of patients diagnosed with initial mildly dyskaryotic smear during the year 2000 with a follow‐up period of 48 months. These women had not had any previous abnormal smears. Settings: Cytopathology Department and Colposcopy Unit, King’s College Hospital, London, UK. Results: We identified 524 patients of whom 375 patients with complete follow‐up data are included. The age range was 19–67 years with a median of 29 years. There were 207 patients aged 35 years or less (55%). At 6 months, 258 smears were performed and 47.8% of them were negative (95% CI: 41.6–54.0%). The total number of negative follow‐up smears in the first year was 198 out of a total of 397 smears performed (50%). This proportion has significantly increased between 1 and 4 years’ follow‐up to 67.5% (RR: 1.24; 95% CI: 1.14–1.35). Over the 4‐year period, 791 smears were performed and 477 were negative (60.3%; 95% CI: 56.9–63.7%). Of the 477 negative smears there were only 61 smears (12.8%; 95% CI: 10–16%), in 54 patients (14%; 95% CI: 11–18%) that reverted back to low‐grade cytological abnormality. In only one case the repeat smear showed high‐grade abnormality after initial negative follow‐up; however, on biopsy, histology showed CIN I. Out of the 375 patients, 70 required treatment with excisional biopsy (19%; 95% CI: 15.0–22.9%). Histology confirmed high‐grade CIN in only 41 cases giving a prevalence of 11% (95% CI: 8.1–14.5%). There were no cases of microinvasive or invasive cancer detected. Age (≤35 years versus >35 years) did not significantly affect either cytological or histological outcome. Conclusion: Sixty per cent of follow‐up smears after initial mild dyskaryosis subsequently became negative; of them 87.2% remained negative over the 4 year follow‐up. Treatment was only required in 19% of patients, with 11% prevalence of high‐grade CIN. Age did not affect the outcome. These results are reassuring and indicate that colposcopic referral may not be necessary after only one mildly dyskaryotic smear.     

P‐26CONVENTIONAL V THIN LAYER TECHNIQUES: A COMPARATIVE STUDY OF BRONCHIAL SPECIMENS USING CONVENTIONAL AND TWO LBC METHODS,THINPREP AND SUREPATH

Introduction: There is ongoing debate about the terminology used in the classification of dyskaryosis, including whether BNA smears should be classified according to whether koilocytes are present or not. We explored the effect of koilocytosis in the management experiences and clinical outcomes of women with a single BNA smear. Methods: This study includes 410 women aged 20–59 years, resident in Tayside who had an ‘baseline’ BNA smear between 31/10/1999 and 31/10/2002 who were eligible for the TOMBOLA trial but who did not participate. Recommended follow‐up for these women was a repeat smear in six months. Up to three‐years follow‐up data was collected on subsequent cytological smears, colposcopy examinations and any related histology. The baseline smear was re‐read for the presence or absence of koilocytes. Women were classified according to their clinical outcomes during their three years. Results: 47% (192/410) of women were classified as having koilocytosis at baseline. The mean age was lower among these women (25 years) compared to those without koilocytosis (35 years). 55% (105/192) of women with koilocytosis at baseline had one or more negative smears and no further abnormal smears, compared to 63% (137/218) of those without koilocytosis, the difference was not statistically significant. 28% (53/192) of women with koilocytosis at baseline were referred to colposcopy after subsequent low‐grade or high‐grade smears compared to 19% (42/218) of those without koilocytosis; the difference was statistically significant. 14% (27/192) of women with koilocytosis at baseline were diagnosed with CIN2/3 or worse during follow‐up compared to 10% (21/218) of women without koilocytosis; the difference was not statistically significant. Discussion: Our results suggest that the presence or absence of koilocytosis has little impact on the clinical outcomes of women with a BNA smear.     

Cervical intraepithelial neoplasia grade III (CIN III) and invasive cervical carcinoma: the yawning gap revisited and the treatment of risk

In a 3-year study of the population of Southampton and south-west Hampshire there were 10 times as many cases of CIN III compared with invasive squamous carcinoma (700 compared with 70). The peak incidence of CIN III per 1000 screened women years was in those aged 25-29 years, which was 20 years earlier than the peak incidence of invasive cervical cancer per 1000 women years at risk. Ninety percent of CIN III was diagnosed in women under 50 years. There were 14 cases of cervical glandular intraepithelial neoplasia grade III (CGIN III), three coexisting with CIN III, all in women aged under 50 years: the gap between intraepithelial and invasive lesions was not seen for glandular neoplasia. Although referral was for at least moderate dyskaryosis in 86.8% of women with CIN III or CGIN III, most had been screened previously, either having had mild abnormalities requiring repeat cytology (39.8%) or negative cytology (34.5%). Only 12 women aged > or = 50 years had previous negative cytology: 21.4% compared with 35.6% of women aged < 50 years (P = 0.034). The results of this study suggest that the best opportunity for preventing invasive squamous cell carcinoma lies in screening women aged 20-39 years when the incidence of CIN III in the screened population is highest and before the peak incidence of invasive disease. The results also indicate the importance of repeated screening and follow up of minor cytological abnormalities in the detection of CIN III. The benefit of screening must be regarded as a treatment of risk, since it is almost certain that a high proportion of CIN III regresses or persists unchanged.     

Management of women with mild and moderate cervical dyskaryosis.

OBJECTIVE--To compare the outcomes in women with mild and moderate dyskaryosis after increasing periods of surveillance and thereby to define a rational protocol for managing such women. DESIGN--Prospective study with randomisation of women to one of four treatment groups, each with a different period of surveillance; one group in which the women were given immediate treatment and three other groups in which the women were under surveillance for six, 12, and 24 months. SETTING--A dedicated colposcopy clinic in Aberdeen, Scotland. SUBJECTS--902 women who presented with a mildly or moderately dyskaryotic smear for the first time. INTERVENTIONS--Cytological and colposcopic examinations at intervals of six months until the allocated period of surveillance was completed, at which time biopsy was performed. Women with severe dyskaryosis were withdrawn from surveillance and a biopsy was performed. MAIN OUTCOME MEASURES--The histological findings after punch biopsy or large loop excision of the transformation zone, and the trends in cytological appearances of serial cervical smears. RESULTS--793 women completed the study. In all, 769 women had an adequate final smear, of which 197 were normal cytologically, 328 were still mildly or moderately dyskaryotic, and 244 were severely dyskaryotic. Seventeen of the 67 (25%) women with one repeat smear showing non-dyskaryosis had cervical intraepithelial neoplasia grade III compared with only one of the 31 (3%) women with no dyskaryosis in four repeat cervical smears (P < 0.0001). None of the women had invasive cancer. Of 158 women whose index smear showed mild dyskaryosis and who were allocated to the group under surveillance for two years, only 40 had not defaulted or still had dyskaryotic smears by the end of the two years. CONCLUSION--Cytological surveillance, although safe, is not an efficient strategy for managing women with mildly abnormal smears. Women with any degree of dyskaryosis in a smear should be referred for colposcopy.     

Proffered Papers 10.30–11.15 Monday 15 September 2003 3 5 year outcome of women with borderline and mild dyskaryosis smears 3 5 year outcome of women with borderline and mild dyskaryosis smears

Aims

• 1 To identify the outcome status of women with borderline and mild dyskaryosis smears.
• 2 To determine whether the presence or absence of koilocytosis influences the outcome status.
• 3 To identify the proportion of women with borderline smears showing koilocytosis.

Materials and methods Borderline and mild dyskaryosis cervical smears diagnosed during January to March 1997 were identified from the laboratory database. Each slide was reviewed by two researchers independently, who then agreed a final consensus diagnosis. All slides were classified according to the presence or absence of koilocytosis. Slides were excluded from the study if the review diagnosis was negative, inadequate or high‐grade dyskaryosis. The outcome status was classified according to the worst lesion identified histologically and/or cytologically during the 5‐year follow‐up period. Results 1974 women were identified with borderline or mild dyskaryosis cervical smears of which 1597 were included in the study. Table 1 shows the outcome status of these women.

Table 1. . The outcome status of these women

Five-year follow-up of women with borderline and mildly dyskaryotic cervical smears

This study investigated the 5-year follow-up status of women with cervical smears showing borderline nuclear changes (BNC) or mild dyskaryosis and the effect of koilocytosis on the outcome. Thirteen per cent of women with cervical smears showing BNC had high-grade cervical intraepithelial neoplasia (CIN). In contrast, 28% of women with cervical smears showing mild dyskaryosis had high-grade CIN. The presence of koilocytosis (24% for borderline smears and 34% for mild dyskaryotic smears) did not appear to influence the risk of developing high-grade CIN. Our results suggest that the simultaneous implementation of the British Society for Clinical Cytology proposed terminology and the colposcopy guidelines from the British Society for Colposcopy and Cervical Pathology could have an impact on colposcopy services.     

The use of the 'borderline' category in the reporting of cervical cytopathology in the UK: results of a survey conducted under the aegis of the British Society for Clinical Cytology

Objective: To determine how the ‘borderline’ category was used by cytopathologists in the UK when reporting cervical smears. Methods: A questionnaire was sent by email to members of the British Society for Clinical Cytology. Results: There is wide variation in the use of the ‘borderline’ category in the UK but the majority of respondents (77.6%) used it when reporting smears that were either on the borderline between negative and low grade squamous dyskaryosis (‘borderline ?low grade’), or on the borderline between negative and high grade squamous dyskaryosis (‘borderline ?high grade’), or on the borderline between negative and glandular dyskaryosis ‘borderline ?glandular dyskaryosis’). A significant minority (15.7%), however, did not use ‘borderline’ when reporting smears that showed an abnormality that was possibly high grade squamous dyskaryosis. A majority (79.1%) of respondents thought that it would be useful to have separate reporting categories for ‘borderline ?low grade’ and ‘borderline ?high grade’. Conclusions: There is diversity in the use of the category ‘borderline’ in the UK. The proposed revised BSCC terminology with separate categories for borderline ?low grade, borderline ?high grades and borderline ? glandular dyskaryosis reflects the opinion of the majority of respondents to the questionnaire.     

Koilocytosis; an indication for conservative management

The management of women with mild dyskaryosis continues to be the subject of debate. The management of cases with such smears could be improved if additional morphological features were found to be indicative of low/high grade cervical intraepithelial neoplasia (CIN). Our own experience in the routine audit of the diagnostic accuracy of cervical smears had suggested that cases of dyskaryosis with koilocytosis were associated with a low risk of CINIII. Two hundred and forty-four cervical smears reported as showing evidence of wart virus infection were reviewed and their subsequent histories noted. Of these smears, 173 demonstrated clear evidence of koilocytosis. Irrespective of the initial grade of dyskaryosis, only 28 cases (16.2%) had underlying CIN or had progressed to CIN over a minimum follow-up period of 21 months. Only two cases (1.2%) showed evidence of CINIII. Koilocytosis is associated with a low risk of CIN and an especially low risk of CINIII. The management of women with koilocytic smears should be modified accordingly.     

Koilocytosis; an indication for conservative management

The management of women with mild dyskaryosis continues to be the subject of debate. The management of cases with such smears could be improved if additional morphological features were found to be indicative of low/high grade cervical intraepithelial neoplasia (CIN). Our own experience in the routine audit of the diagnostic accuracy of cervical smears had suggested that cases of dyskaryosis with koilocytosis were associated with a low risk of CINIII. Two hundred and forty-four cervical smears reported as showing evidence of wart virus infection were reviewed and their subsequent histories noted. Of these smears, 173 demonstrated clear evidence of koilocytosis. Irrespective of the initial grade of dyskaryosis, only 28 cases (16.2%) had underlying CIN or had progressed to CIN over a minimum follow-up period of 21 months. Only two cases (1.2%) showed evidence of CINIII. Koilocytosis is associated with a low risk of CIN and an especially low risk of CINIII. The management of women with koilocytic smears should be modified accordingly.     

Outcome of women with index smear showing mild dyskaryosis: effects of age and evidence of HPV infection

OBJECTIVE: Recent national guidelines (NHSCSP Document 20) recommend colposcopy referral after one mildly dyskaryotic smear, compared with the current practice of cytological surveillance and referral if the abnormality persists. The aim of this study was to identify the percentage of women whose first abnormal smear, showing mild dyskaryosis, returned to normal with cytological surveillance. Colposcopy could therefore be avoided in this group. This study also assessed whether age or human papillomavirus (HPV) status affected this outcome and the impact of non-attenders on the reliability of surveillance. METHODS: This was a retrospective study examining the follow-up of 1484 women whose first abnormal smear showed mild dyskaryosis between 1996 and 1998. The possible outcomes were: persisting abnormality referred to colposcopy, follow-up by cytology alone (negative follow-up), lost to follow-up or moved out of the area. Results were further assessed in terms of age (over or under 35 years) and cytological evidence of HPV effect. RESULTS: In this study 50.9% of women, presenting with a mildly dyskaryotic smear, returned to normal without colposcopy within the follow-up period of 6-8 years. Age (over/under 35) or cytological evidence of HPV did not significantly affect this figure. CONCLUSIONS: Immediate colposcopy would overtreat 50% of the study group resulting in 159 extra colposcopies in this unit per year. High-grade abnormalities were twice as prevalent (22% versus 11%) in the younger age group, suggesting that younger rather than older women would benefit from immediate referral.     

The Cardiff Cervical Cytology Study: prevalence of cytological grades and initial histological findings.

Among 45 266 women in the Cardiff Cervical Cytology Survey the peak prevalence of suspicious or positive smears was 11.2/1000 at age 45-50 years and of dyskaryosis 10.2/1000 at age 25-29. A suspicious or positive cytological picture at prevalence testing was associated with occult or clinical invasion in 24% of cases, and only 4% of patients with suspicious or positive smears were normal histologically. When dyskaryosis was detected in the prevalence test 20% had carcinoma in situ or microinvasion and 3% had occult or clinically invasive carcinoma. One hundred and twenty-nine (51%) women with dyskaryotic smears did not have a biopsy initially (that is, within two years of the prevalence test), but they were followed up at regular intervals. Subsequently 15 of the 129 gave smears consistently dyskaryotic or worse cytologically and were subjected to biopsy. Of these, two showed dysplasia, 12 carcinoma in situ, and one clinically invasive carcinoma. These findings emphasise the need for repeat cytological or histological examination in any woman with evidence of dyskaryosis in a cervical smear.