Cigarette smoking and histological outcome in women with mildly dyskaryotic cervical smears

A review of smoking cessation services in women attending colposcopy clinics in Scotland

The most common reason for women being referred to colposcopy clinics is an abnormal smear suggesting pre-cancerous change within the cervix. It has been demonstrated that in women with low-grade lesions, smoking cessation led to a reduction in size of the cervical lesion over a 6-month period. Smoking is also recognised as an independent risk factor for treatment failure of cervical intraepithelial neoplasia. As 'stop smoking' services have become an integral part of the colposcopy clinic at St John's Hospital, Livingston, a national survey was undertaken. The aim of the survey was to establish what smoking cessation information, advice and support is available in colposcopy clinics throughout Scotland, and if staff had attended standardised training on raising the issue of smoking. The study demonstrated that 52% of colposcopy clinics in Scotland always establish smoking status but only 37% of clinics discuss the benefits of smoking cessation in relation to abnormal cervical smears. There was inaccurate and inconsistent written and verbal advice given on the benefits of cessation and whether women should cut down or stop smoking completely. The majority of staff had not attended standardised training on how to raise the issue of smoking and very few clinics have established referral pathways for smoking cessation support.

Using patient history to predict high-grade cervical dysplasia and cancer in women with borderline cervical cytologic results

OBJECTIVE

To determine whether demographic and lifestyle factors can be used to triage women with borderline cervical cytologic results.

MATERIALS AND METHODS

Demographic and medical information were collected from women undergoing colposcopy for a cytologic result read as atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion in the gynecology clinic of an urban public hospital between July 1, 1996, and December 1, 1999. Colposcopy and subsequent histologic results were reviewed. Multivariate analysis was used to define predictors of high-grade cervical disease.

RESULTS

From among 1725 eligible women, 283 women (16%) with ASCUS or low-grade squamous intraepithelial lesion results were found to have high-grade cervical disease (113 women with ASCUS results [13%] and 170 women with low-grade squamous intraepithelial lesion results [21%]). In multivariate analysis, pregnant women were less likely to have high-grade disease (odds ratio, 0.36; 95% CI, 0.17-0.79). Women with three or more lifetime sexual partners were more likely to have high-grade disease (odds ratio, 1.75; 95% CI, 1.31-2.34). However, a triage scheme tracking pregnant women with fewer than three lifetime partners to observation without colposcopy would have excluded only 51 of the 1725 women eligible (3%). Other combinations of risk factors had inadequate sensitivity or specificity for high-grade disease. Separate models for ASCUS showed that only having fewer than three lifetime sexual partners was associated with lower risk of high-grade histologic results (odds ratio, 0.56; 95% CI, 0.36-0.89), but excluding women with fewer partners would have missed 27 of 110 cases (25%) of high-grade disease.

CONCLUSIONS

History and demographic information are inadequately sensitive for use in triage of women with borderline cytologic findings. Colposcopy or triage using human papillomavirus DNA tests remain indicated.

Cigarette smoking and cervical cancer: Part I: a meta-analysis

Cancer of the cervix is the third most common cancer among women worldwide and its etiology is not clearly understood. Human papillomavirus can be found in approximately 95% of cervical cancers, but it does not appear to be necessary or sufficient to induce malignancy. In 1977, Winkelstein suggested that cigarette smoking was a causative factor in the development of cervical cancer. We report a meta-analysis of cigarette smoking and cervical disease and conclude that the data support a role for cigarette smoking as a risk factor for cervical cancer. We propose a multifactorial hypothesis involving a virus-tar interaction as the etiology of cervical cancer.

Persistent human papillomavirus infection and smoking increase risk of failure of treatment of cervical intraepithelial neoplasia (CIN)

Women with abnormal smears have an increased risk of developing cervical cancer. During the 8 years following conservative treatment of cervical intraepithelial neoplasia (CIN), their risk of invasive cervical cancer is about 5 times greater than that of the general population. Human papillomavirus (HPV) has been associated with the natural history of both CIN and cervical cancer. To date, there have been no published reports on the predictive value of HPV testing in the treatment outcome of CIN. A prospective, multi-center, cohort study was conducted on women in the Northwest of England who were attending for treatment of CIN. They were asked to complete a questionnaire, which included a detailed smoking history. Pre- and post-treatment HPV testing was performed on cervical biopsies and cervical swab, being taken with the first follow-up smear at 6 months. A nested case-control analysis was performed, cases being defined as women who developed CIN within the 2 years of treatment and controls being sampled from those who did not experience treatment failure within 2 years. Multiple conditional logistic regression is used to study the factors associated with treatment failure of CIN. The cohort included 958 women of whom 77 (8%) experienced treatment failure (cases). Two controls were matched to each case (154). Smoking status was significantly associated with CIN treatment failure(p= 0.0013). Current smokers had a 3-fold increased risk of treatment failure of CIN as compared to non-smokers (95% CI 1.65 to 5.91). Five hundred twenty-five women underwent HPV sampling following treatment, of whom 47 (8.9%) developed further CIN. Post-treatment positive HPV testing was found to be strongly associated with treatment failure of CIN (OR 23.3; 95% CI 3.15-172.1). In 11/45 cases with negative smear at first follow-up, the HPV test was positive. The combination of both HPV and cytology in the first follow-up visit predicted treatment failure in 72% of the cases. Cigarette smoking is a factor, which, independently of HPV infection, influences the treatment outcome of CIN. Smokers and those who are HPV positive during follow-up appear to require longer, more intensive follow-up. HPV testing requires careful consideration as part of routine follow-up protocol following treatment of CIN.

Cigarette smoking and cervical dysplasia among non-Hispanic black women

This is the first case-control study to determine whether smoking is associated with cervical dysplasia, after adjustment for human papillomavirus (HPV) infection, among a group of non-Hispanic black women. Subjects were interviewed and asked questions about smoking and other risk factors for cervical cancer. HPV infection was determined by hybrid capture. Thirty-two women with histologically confirmed incident dysplasia and 113 control women with normal cytologic smears were enrolled; all women were HIV negative. Smoking was more strongly associated with dysplasia among women with high-grade lesions than among all case women combined. After adjustment, women with high-grade lesions were roughly four times more likely to be ever (odds ratio [OR]: 3.8; 95% confidence interval [CI]: 0.76-18.4) or current (OR: 4.3; 95% CI: 0.83-21.9) smokers, compared with control women. Larger studies among black women that control for HPV infection are needed to confirm these findings and to explore associations among black women with low-grade lesions.

Tubal sterilization and use of an IUD and risk of cervical cancer

The relationship of tubal sterilization and use of an intrauterine device (IUD) to the risk of invasive squamous cell cervical cancer was evaluated in a case-control study carried out in Shandong, China, from 1989 to 1991. Patients (cases) were 272 women aged 30-77 years with newly diagnosed invasive squamous cell cervical cancer in Shandong Province Tumor Hospital. Controls were 893 randomly selected screened women matched to the cases by age (within 2 years) and county. A decrease in risk was observed in uses of an IUD, especially in long-term users under age 33. A nonsignificant decrease in risk in women under age 33 who had had a tubal ligation was also observed, especially in the first 10 years since the procedure. Tubal ligation and IUD insertion and removal provide opportunities to screen women for cervical cancer and reduce the risk of invasive disease.

Can the number of cigarettes smoked predict high-grade cervical intraepithelial neoplasia among women with mildly abnormal cervical smears?

OBJECTIVE

We investigated whether the number of cigarettes smoked by women who had mildly abnormal cytologic study results could identify those at risk for high-grade dysplasia.

STUDY DESIGN

This was a prospective study of all women who were referred for colposcopy with a mildly abnormal cervical smear over a 4-year period. A detailed questionnaire was completed that evaluated sociodemographic characteristics including smoking history. Colposcopy then determined the degree of disease.

RESULTS

One hundred seventy-three women were referred with a mildly abnormal cervical smear. There was a significant relationship between the numbers of cigarettes smoked and the risk of high grade disease (P = .007). Once the number of cigarettes smoked daily exceeded 20, the risk of high grade cervical intraepithelial neoplasia was increased fivefold (odds ratio 5.85 [95% confidence interval 1.92 to 17.80]).

CONCLUSION

Cigarette smoking is associated with a dose-dependent increased risk of cervical intraepithelial neoplasia grade 2 or 3 among women who have mildly abnormal cervical smears.

Can women at risk of cervical abnormality be identified?

OBJECTIVE

To determine if use of a detailed risk factor profile accurately predicts the presence of cytological abnormality of the cervix or improves the appropriateness of referral for colposcopic assessment when women are found to have these abnormalities.

DESIGN

Cross-sectional survey.

SETTING

Family planning clinic.

POPULATION

1219 consecutive women, aged between 15 and 19 years, attending for contraceptive advice. Variables included age, social class, educational status, hormonal and obstetric history, smoking and alcohol habits, history of sexually transmitted diseases, the age of first intercourse, number of sexual partners, duration of each relationship, frequency of intercourse, contraception used and the age of each partner.

MAIN OUTCOME MEASURES

Presence or absence of cytological abnormality and the presence or absence of histological abnormality in those with cytological abnormality referred for colposcopic assessment.

RESULTS

Univariate analysis confirmed many of the known associations of cervical abnormality. Discriminant analysis identified five independent significant predictors of cytological abnormality and four independent predictors of dyskaryotic cytology. At best models, derived from identified variables correctly predicted 10.1% of individuals with cytological abnormality and 13.5% of those with dyskaryotic cytology. Of those referred for colposcopic assessment because of abnormal cytology, models were able to predict 23.5% of those with histological evidence of cervical intraepithelial neoplasia.

CONCLUSIONS

Despite the availability of detailed information regarding the known correlates of cervical neoplasia in this age group, it was not possible to identify the majority of women with cervical abnormality. It is concluded that the strength of these associations is not sufficient to allow useful prediction of membership of a high risk group.

Aetiology, pathogenesis, and pathology of cervical neoplasia

Early epidemiological studies of cervical neoplasia suggested a causal relation with sexual activity and human papillomaviruses (HPVs) have emerged as prime suspects as venerally transmitted carcinogens. HPVs fall into two broad camps: low risk types, associated with cervical condylomas and CIN 1; and high risk types (mostly 16 and 18), found in 50-80% of CIN 2 and CIN 3 lesions, and 90% of cancers. This association with cancer is very strong, with odds ratios of > 15 (often much higher) in case-control studies that are methodologically sound. An infrequently detected third group of intermediate risk type HPVs is associated with all grades of CIN and occasionally with cancers. HPVs have also been detected in a wide range of asymptomatic controls, indicating that other events are required for development of neoplasia such as viral persistence and/or altered expression of viral genes, often following integration of the viral genome. This leaves the two major viral oncogenes, E6 and E7, directly coupled to viral enhancers and promoters, allowing their continued expression after integration. High risk HPV E7 proteins bind and inactivate the Rb protein, whereas E6 proteins bind p53 and direct its rapid degradation. A range of putative cofactors has been implicated in progression: HLA type, immunosuppression, sex steroid hormones, and smoking; most of these cofactors appear to influence progression to CIN 3. The natural history includes progression to CIN 3 in 10% of CIN 1 and 20% of CIN 2 cases, whereas at least 12% of CIN 3 cases progress to invasive carcinoma. Cervical glandular intraepithelial neoplasia (CGIN) often coexists with squamous CIN, and the premalignant potential of high grade CGIN is not in doubt, but the natural history of low grade CGIN remains uncertain. A high proportion of CGIN lesions and adenocarcinomas are HPV positive, and HPV18 has been implicated more in glandular than in squamous lesions. A strong clinical case for the application of HPV typing of cells recovered from cervical scrapes can be made; however, a rigorous cost-benefit analysis of introducing HPV typing into the cervical screening programme is required. Prophylactic and therapeutic HPV vaccines are under development. This article reviews the aetiology, pathogenesis, and pathology of cervical neoplasia, emphasising the role of HPVs.

Histology corresponding to mildly dyskaryotic smears--a study of 190 laser cone biopsied patients

OBJECTIVES

The aim of the study was to evaluate the histological outcome of laser ring biopsies in patients with one or more smears showing cytological mild dyskaryosis where punch biopsies were not performed. The possibilities of predicting histological findings of CIN 2 and CIN 3 were analyzed.

METHODS

The study comprised 190 laser ring biopsied patients with mildly dyskaryotic smears. Eighty-five patients were excluded from the initial 275 because of up- and downgrading of smears. Conization specimens and smears were reviewed by an experienced histopathologist and two experienced cytotechnicians. The histological findings were correlated to smear findings.

RESULTS

Histologically, CIN 2 was found in 60 and CIN 3 in 45 patients (31 and 24%, respectively). The incidence of histological CIN 3 was higher in those with two or more mildly dyskaryotic smears and in those dyskaryotic smears lacking koilocytic change. Mildly dyskaryotic smears without endocervical cells indicated higher incidence of histological CIN 3. The fact that 36 of 96 CIN 2 and 3 lesions (38%) involved only 3 mm or less of the mucosa might be one important explanation for the absence of representative cells in the corresponding smears.

CONCLUSIONS

Our study has shown that a mildly dyskaryotic smear is a strong indicator of CIN 2-3 histologically, especially in those cases without koilocytic cells and in those with repeatedly abnormal smears. The importance of inadequate sampling is indicated by higher incidence of histological CIN 3 in those with less than optimal smears. These findings are some of the factors to be taken into account when planning treatment strategies for this group of patients.

Effect of smoking cessation on cervical lesion size

BACKGROUND

Cigarette smoking has been postulated as a cofactor in the aetiology of cervical cancer, but a causal role is difficult to establish because of potential confounding by sexual behaviour. We have investigated the effect of cessation or reduction of cigarette smoking on the course of minor-grade cervical lesions.

METHODS

In this intervention study 82 women volunteers with minor-grade lesions on colposcopy (cervical intraepithelial neoplasia grade 1 or less) attempted to give up smoking for 6 months. Smoking histories were taken at 3-monthly clinic visits and verified by measurement of salivary cotinine concentrations. At each clinic visit, a photograph of the cervix was taken; the image was digitised and computer-aided image analysis was used to assess lesion size, by investigators unaware of smoking status.

FINDINGS

Of the 82 women, 17 stopped smoking completely for at least 6 months and 11 others reduced their smoking consumption by more than 75%. Of these 28 women, 23 (82%) showed a reduction in lesion size of at least 20% or 4 mm2 compared with 13 (28%) of the 47 non-quitters (odds ratio 12.0 [95% Cl 3.9-32.7]). The remaining seven women had unconfirmed smoking histories. There was a significant correlation between the extent of smoking reduction and the change in lesion size (chi2 for trend=31.55, p<0.0001). Adjustment for social class, method of contraception, and stage of menstrual cycle did not affect the results.

INTERPRETATION

Our findings support a link between smoking and cervical disease and suggest that smoking cessation could have a beneficial effect on early cervical abnormalities.

The suitability of DNA cytometry for the prediction of the histological diagnosis in women with abnormal cervical smears

OBJECTIVE

To analyse the suitability of DNA cytometry for predicting the histological diagnosis in women with cervical dyskaryosis.

DESIGN

Survey with the use of diagnostic information to revise disease probability.

SETTING

Colposcopy clinic of a university hospital.

PARTICIPANTS

One hundred and ten women with two mildly or moderately dyskaryotic cervical smears and 98 women with one severely dyskaryotic smear.

INTERVENTIONS

DNA cytometric analysis using cytocentrifuge preparations of single cell suspensions from a cervical scrape. The main DNA cytometric parameter was N5C (i.e. the absolute number of cells with a DNA content of more than 5C on a given surface with a predefined cell density).

MAIN OUTCOME MEASURE

The probability of finding CIN II or worse. On arbitrary grounds, a positive test should point to a probability of 85% or higher.

RESULTS

In the patients with cervical neoplasia, the value of N5C increased significantly with an increasing CIN grade (P < 0.001). In the patients with one severely dyskaryotic smear and in those with two mildly or moderately dyskaryotic smears, the prior probability of finding CIN II or worse was 94% and 53%, respectively. Therefore, DNA cytometric analysis might be particularly useful in women with mild or moderate dyskaryosis; further analysis was restricted to this group. All of the women in whom the N5C value was higher than 52 were diagnosed as having CIN II or worse. Only 16 (14.5%) of the 110 women had an N5C value of 52 or higher. When the N5C value was 27, the probability of finding CIN II or worse was estimated to be 85%. Only 28 (25%) patients had an N5C value of 27 or higher.

CONCLUSIONS

DNA cytometry produced significant diagnostic information, as was shown by the relation between N5C and the histological diagnosis. However, the N5C value could not discriminate sufficiently between women with CIN II or worse and CIN I or better. Therefore, the management of individual patients with cytological abnormalities cannot be based on the results of DNA cytometric analysis.

The significance of mild squamous atypia on cytology

Between January, 1991 and February, 1993 inclusive, 396 Papanicolaou smears were reported to show Mild Squamous Atypia with or without Human Papilloma Virus (MSA +/- HPV). All women with MSA +/- HPV smears were routinely recalled for colposcopy. To determine the significance of MSA +/- HPV on routine smear screening, the records of all patients were reviewed. Three hundred and thirty-seven women (85.1%) attended the colposcopy clinic and are the subjects analyzed for this report. The remaining 59 (14.9%) failed to attend. Intraepithelial neoplasia was found in 61 patients (18.1%), of whom 27 (8.0%) had a high grade lesion (CIN 2 or 3 or GIN 2). No patient had invasive cancer of the cervix. Only 1 of the 45 pregnant women had a significant lesion. It is concluded that all asymptomatic women with MSA +/- HPV on cervical smear may be managed in accordance with the current NH and MRC recommendations (1) and have a repeat smear in 6 months and colposcopy if the abnormality persists at 12 months.