Cervical dysplasia: association with sexual behavior, smoking, and oral contraceptive use?

Pharmacodynamics of combined estrogen-progestin oral contraceptives: 4. Effects on uterine and cervical epithelia

Introduction: Steroid hormones are responsible for specific changes in the endometrium during the menstrual cycle, when they are sequentially secreted and, because of this, in the early days sequential combined oral contraceptive regimens were utilized. The same basic concept has been utilized with multi-phasic regimens, in order to produce endometrial pictures mimicking the normal cycle.Areas covered: The Endometrial effects of progestins and estrogens; combined monophasic high- (50 μg), medium- (30 μg), low- (20 μg), ultralow- (15 μg) estrogen content; sequential regimens; multiphasic combinations; treatment schedules.Cervical effects of combined high-dose and sequential combinations, including evidence for an increase in malignant lesions.Expert opinion: Overall, combined oral contraceptives (COCs) inhibit normal proliferative changes and the endometrium becomes thin, narrow, with widely spaced glands and pre-decidual changes in the stroma. During the first few cycles the progestin induces a coexistence of proliferative and secretory features; with time, the picture changes because the progestin induces a down-regulation of estrogen receptors, resulting in tortuous glands similar to those in the secretory phase, but characterized by a quiescent, atrophic glandular epithelium.In the cervical epithelium, under the influence of high-dose COCs, endocervical glands became hypersecretory and in some instances, distinctive type of atypical polypoid endocervical hyperplasia is found.

Factors Affecting Gynecologic and Sexual Assessment in Older Women: A Lesson for Primary Care Providers

Guidelines for screening of cervical cancer and pelvic exams for older women have recently changed. These changes may have unexpected sequelae in women over 65 years of age. This manuscript provides a review of gynecologic screening recommendations for older women in the U.S. and potential ramifications of these recent changes. Peer reviewed guidelines from the American College of Obstetrics and Gynecology, U.S. Preventative Task Force Services, the American Cancer Society, The Centers for Disease Control, and multiple original research articles and reviews were reviewed for this manuscript. Women over 65 are at greatest risk to develop late stage diagnoses of cancers, pelvic organ disease, incontinence, and infections. Clinicians will need to acutely consider this fact when communicating and screening this population. We conclude that practitioners should be aware of the new guidelines and should consider including gynecologic health history and symptom analysis as part of annual exams in women of all ages.

The interplay between secondhand cigarette smoke, genetics, and cervical cancer: a review of the literature

Research has suggested a link between smoking and cervical cancer; however, little data are available on secondhand smoke (SHS) exposure and cervical cancer risk. This article reviews the literature on the links among smoking, SHS exposure and cervical cancer. The review was based on a search of electronic databases. The research reviewed clearly showed that smoking increases cervical cancer risk through myriad mechanisms that interact with genetics and the pathologic processes leading to cervical cancer. However, less is understood about the role of SHS in cervical cancer. With new technology enabling scientists to examine how genomic structure responds to environmental stimuli, more information should be forthcoming on links between SHS exposure, biomarkers, and genetic changes involved in the development of cervical cancer.

The nocebo effect for women in waiting

This paper, drawn from a larger phenomenological study, critiques the effects of "waiting" for women when they have an abnormal Pap test result. The hurt and injury incurred by women who perceive they have no choice but to become patient waiters in a health system that seemingly values the time of the health care provider over the health care recipient is discussed. These iatrogenic, unintended, harmful consequences are referred to as the nocebo effect. The participants provide the principal voices and their stories are dialogued to a lesser degree with the literature and the discourse of critical theorists who question power relationships in health professional practice. The purpose of this paper is served when the women's stories strip away some of the taken-for-granted, invisible aspects of the health professional's power.

Changes in lipid peroxidation and antioxidant trace elements in serum of women with cervical intraepithelial neoplasia and invasive cancer

This study investigated serum lipid peroxidation, antioxidant capacity, and trace element levels in Korean women as related to uterine cervical neoplasia. Twenty-eight subjects had cervical intraepithelial neoplasia (CIN), 36 had invasive cervical cancer, as determined by a colposcopically directed biopsy, and controls included 44 subjects with normal colposcopic findings. Significantly lower selenium (Se) and zinc (Zn) levels and higher copper/Zn ratios were found in both CIN and cancer patients compared with the controls. Serum malondialdehyde levels decreased significantly in the order CIN>cancer>control, implying the involvement of reactive oxygen species at the precancerous stage, that is, prior to progression into invasive cervical cancer. Serum glutathione peroxidase activity was significantly lower in patients with CIN or cancer than controls, and total antioxidant ability decreased from controls to CIN to cancer (P < 0.0001). This study demonstrated the involvement of lipid peroxidation, decreased Se and Zn levels, and an impaired serum antioxidant system in the pathogenesis of cervical dysplasia. Further research is needed to examine the possibility of an effective chemopreventive treatment in cervical cancer based on enhancing the endogenous antioxidant system.

Passive cigarette smoking is a risk factor in cervical neoplasia

OBJECTIVES

To determine the role of spouse's cigarette smoking in the detection of high-grade squamous intraepithelial lesions of the cervix.

DESIGN

Prospective cohort study with multivariate analysis.

SETTING

Colposcopy clinic in a tertiary hospital.

PARTICIPANTS

Women referred to a colposcopy clinic for evaluation of abnormal Papanicolaou smears showing either repeated inflammatory changes, low-grade squamous intraepithelial lesion (LSIL), or high-grade squamous intraepithelial lesion (HSIL). Data collection. The women were interviewed with a structured questionnaire for sexual history, use of oral contraceptive pills, personal and spouse cigarette-smoking history, and obstetric history.

RESULTS

There were 623 women in the cohort. They were grouped into normal, LSIL, and HSIL categories based on colposcopy and histologic assessment. There were very few women who had had more than one sexual partner or a history of sexually transmitted diseases (STDs). The prevalence of oral contraceptive pill usage was 2.9% among the women in the normal group, 4.3% in women with LSIL, and 5.1% in women with HSIL. The incidence of cigarette smoking by the women was 2.5%, 3.2%, and 6.8% for the three groups of women, respectively. The incidence of spouse cigarette smoking was 25%, 35%, and 43% respectively. Compared to women in the normal group, women with HSIL were younger at first sexual intercourse, more likely to smoke cigarettes, and have spouses who smoked cigarettes. After controlling for age, age at first sexual intercourse, usage of combined contraceptive pills, and the woman's own cigarette-smoking habit, the odds ratio for HSIL was 1.046 for every stick of cigarette smoked by the spouse. In other words, the risk of detection of HSIL increased by 4.6% for every stick of cigarette her spouse smoked.

CONCLUSIONS

Among women attending a colposcopy clinic, the risk of detection of HSIL increases with the spouse's cigarette-smoking habit. Further studies are warranted in quantifying the risk in a general population.

Meta-analysis of social inequality and the risk of cervical cancer

Previous studies of the relationship between socio-economic status and cervical cancer have been mainly based on record linkage of routine data, such as cancer registry incidence rates and regional measures of social class based on census data. These routine data are liable to substantial misclassification with respect to socio-economic status. Previous reports are also primarily from developed countries, whereas the major burden of cervical cancer is in developing countries. We have therefore pooled the data from previously reported case-control studies of cervical cancer or dysplasia, which contain individual-level information on socio-economic characteristics to investigate the relationship between cervical cancer, social class, stage of disease, geographical region, age and histological type. Based on 57 studies, we found an increased risk of approximately 100% between high and low social class categories for the development of invasive cervical cancer, and an increased risk of approximately 60% for dysplasia, including carcinoma in situ. Although the difference was observed in all countries, it was stronger in low/middle income countries and in North America than in Europe. No clear differences were observed between squamous cell carcinoma and adenocarcinoma, or between younger and older women. These results indicate that both cervical infection with human papillomavirus, which is linked to both female and male sexual behaviour, and access to adequate cervical cancer screening programmes are likely to be important in explaining the large cervical cancer incidence rates observed in different socio-economic groups, and that the importance of these factors may vary between different geographical regions.

Young women, cervical intraepithelial neoplasia and human papillomavirus: risk factors for persistence and recurrence

Human papillomavirus (HPV) infection is one of the most common sexually transmitted infections (STIs) in young women. They can occur in one or multiple areas of the female genitalia. Usually, the vulva is the initial site of implantation for HPV. The purpose of our study is to evaluate the epidemiological aspects, incidence of single or multiple lesions in the lower genital tract, correlation between sexual behaviour and their localization and behaviour risk factors for persistence and recurrence of HPV lesions and cervical intraepithelial lesion (CIN) in a long-term follow-up among young women. We recruited 268 patients aged 11-21 years who previously had cytology and/or physical examination suspicious for HPV infection. The women were interviewed and asked information about lifestyle, sexual behaviour, work, personal or family history of genital warts and school attendance. We considered individuals to be 'smokers' if they smoked more than five cigarettes/day. No specific data were recorded about oral contraception, nevertheless, no woman had used oral contraceptives (OCs) for more than 2 years. Young women included in the study were between the age of 12 and 21 years who had HVP lesions after entry examinations and had undergone no treatment for HPV lesions prior to entry. Other exclusion criteria relevant to this study included cervical excisional treatment prior to entry or later. Two hundred and thirty-four young women were included in our study group. Our diagnostic schedule for a complete evaluation included exo- and endocervical cytology, colposcopy, directed biopsy and microcolpohysteroscopy. The treatment was performed with a LASER CO2 Coherent 400, model 451, with Zeiss photocolposcopy attachment. The finding that, among 126/234 (53.8%) adolescents using contraceptives, only 85 (36.3%) have used condom, the only barrier form of contraceptive effectively protecting against virus, shows a low awareness of the high risk for contracting HPV infection among young sexually active women. The sites most frequently affected in our study were vulva, perianus and perineum (194/234), 82.9% and the cervix (125/234), 53.4%. Vaginal lesions were detected only in 29/234 patients (12.3%). According to our data, in 161 patients, sexual habits, age at the first intercourse (P=0.68), frequency of intercourses (P=0.49) and number of lifetime partners (P=0.27) as well as age (P=0.26) play a role in transmission and incidence of HPV infection but not on the location of the lesions. This can be due to a coexistent clinical and subclinical multiple infection as well as a transmission via intercourse or from other sources, including tampons. Abnormal Pap test was related to HPV infection, but the low correlation with colposcopic and histological findings in this study justify the support of other examinations such as colposcopy and punch biopsy for diagnosis. Moreover, according to our data, cytology alone shows to be not suitable to exclude CIN (seven underestimated cases of CIN) and a closer correspondence were found between colposcopy and the result of histological sample after punch biopsy in CIN detection. More attention must be paid to psychological aspect of diagnoses and treatment among adolescents, more than older women as the high rate of patients lost shows in our study: 75/234 (32.05%) before LASER surgery and 55/159 (34.59%) during follow-up. International data shows that only 12-45% of sexually active adolescent girls have obtained Pap smear screening. In our study, we found no correlation between treatment failure and cigarette smoking or between the use of oral contraceptives and persistence/recurrence after LASER CO2 surgery. Because the small sample of our study group, further analyses were required.

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.

The role of steroid contraceptive hormones in the pathogenesis of invasive cervical cancer: a review

Invasive cervical cancer remains a leading cause of morbidity and mortality, especially among women in the developing world where screening is either deficient or absent. Of all agents linked to the causation of this disease, high-risk human papillomavirus (HPV) appears to be the strongest factor. However, not all women with HPV develop cervical cancer. Steroid contraception has been postulated to be one mechanism whereby HPV exerts its tumorigenic effect on cervical tissue. Steroids are thought to bind to specific DNA sequences within transcriptional regulatory regions on the HPV DNA to either increase or suppress transcription of various genes. Although some earlier studies were reassuring as no increased incidence of cervical cancer was observed, subsequent research has shown a causative association, especially among long-term users. The role of steroids was further enhanced by the discovery of hormone receptors in cervical tissue. Some earlier studies of oral contraceptive steroids found no increased risk, even after controlling for other risk factors, including smoking and number of partners. However, prospective studies have shown a greater progression of dysplasia to carcinoma-in-situ with more than 6 years of oral steroid contraceptive use. Similar findings were also evident from other work, including the Royal College of General Practitioners Oral Contraception Study. The WHO Collaborative Study of Neoplasia and Steroid Contraceptives showed a relative risk of 1.2 for invasive cancer in users of the long-acting progestational contraceptive, depo-medroxyprogesterone acetate. However, in users of more than 5 years duration, an estimate of 2.4 was reported. The upstream regulatory region (URR) of the HPV type 16 viral genome, mediates transcriptional control of the HPV genome and is thought to contain enhancer elements that are activated by steroid hormones. It has been shown that steroid hormones bind to specific glucorticoid-response elements within HPV-DNA. Experimental evidence has revealed that high-risk type HPV 16 are able to stimulate the development of vaginal and cervical squamous cell carcinomas in transgenic mice exposed to slow-release pellets of 17 beta-estradiol in the presence of human keratin-14 promoter. Squamous cell carcinomas developed in a multi-stage pathway only in transgenic mice and not in nontransgenic mice. The E6 oncoprotein of HPV 16 has been shown to bind to the p53 tumor suppressor gene and stimulate its degradation by a ubiquitin-dependent protease system. Steroid hormones are thought to increase the expression of the E6 and E7 HPV 16 oncogenes, which in turn bind to and degrade the p53 gene product, leading to apoptotic failure and carcinogenesis. However, the molecular basis of this remains to be proven.

Should gynecologic maturity change the management of cervical cytologic atypia during adolescence?

STUDY OBJECTIVE

To test the hypothesis that atypical cytology (ASCUS) portends ominous histologic diagnoses during adolescence.

METHODS

The prevalence of squamous intraepithelial lesions (SILs) was determined in a racially diverse group of thirty-six 14- to 21-year-olds who were undergoing colposcopic evaluation of ASCUS cytology. The prevalence of 10 widely accepted risk factors for SIL was also qualified.

RESULTS

SILs were detected in biopsies obtained from 20 (56%) of the 36 study subjects. There were 15 (39%) low-grade SILs and 5 (17%) high-grade SILs. No single risk factor or combination of risk factors distinguished subjects with SIL histology from those with more benign diagnoses.

CONCLUSION

The hypothesis was supported. More than half (56%) of the adolescents we studied with ASCUS cytology had SIL histology. The findings suggest that immediate colposcopic evaluation may be prudent for adolescents with ASCUS cytology that cannot be attributed to concurrent lower genital tract infections.

Follow-up of abnormal Papanicolaou smears in a hospital-based adolescent clinic

STUDY OBJECTIVE

To present data on the spectrum of abnormal Papanicolaou (PAP) smears in adolescents and to determine factors that influence compliance with recommendations to return for repeat PAP smears or for colposcopic examination.

DESIGN

Retrospective chart review with follow-up telephone calls to patients who did not follow recommendations for colposcopy.

SETTING

Adolescents receiving health care in a hospital-based adolescent clinic.

PARTICIPANTS

Patients with abnormal PAP smears between July 1, 1994 and June 30, 1995.

MAIN OUTCOME MEASURES

Compliance with follow-up for abnormal PAP smears including referral to the colposcopy clinic, and the results of repeat PAP smears and colposcopy.

RESULTS

Of 888 adolescents undergoing PAP smear evaluation 119 (13.4%) had an abnormal PAP smear during the study year (index PAP). The results of the index PAP were 97 (81.5%) atypia and 22 (18.5%) squamous intraepithelial lesion low grade (SIL LG). The index PAP was the first abnormal PAP smear for 92 of the patients (77%); 27 had one or more previous abnormal PAP smears (18 atypia, 7 SIL LG, 2 SIL high grade [HG]), and 13 had been referred for colposcopy in the past. For 76 of 92 patients with atypia on index PAP (84%), the index PAP was the first abnormal PAP smear. Of these 76 patients, 51 had a second PAP smear: 27 (53%) were normal, 13 (25%) atypia, and 11 (22%) SIL LG. Sixty patients were referred to the colposcopy clinic, but only 37 actually kept the colposcopy appointment despite outreach. The only significant factor for obtaining colposcopy was a visit to the Adolescent Clinic after notification of the abnormal PAP smear result and before the colposcopy appointment; 79% of those who had a visit obtained colposcopy compared with 45% of those who did not have such a visit (p = 0.007). There were no significant differences by race, insurance status, age, PAP smear result, previous referral for colposcopy, or number of reminders with compliance with recommendations for repeat PAP smears or colposcopy.

CONCLUSIONS

Although a sizable proportion of adolescents with abnormal PAP smears have significant pathology on repeat PAP smears, adolescents with abnormal PAP smears have a high failure rate in keeping appointments for follow-up PAP smears and colposcopy. Interventions that target all adolescents with abnormal PAP smears need to be designed and tested to aid follow-up.

Risk factors associated with genital HPV infection

The genital human papillomavirus (HPV) is directly associated with cervical cancer, the second most common form of cancer among women. The study was guided by a synergistic interaction model of HPV risk factors. The relative risk of selected risk factors and cofactors associated with genital HPV infections was identified. Women at highest risk for acquiring an HPV infection had (a) initiated sex before age 15, (b) more than four lifetime sex partners, (c) more than one "once only" sexual partner, and (d) chosen male sex partners who previously had > 16 other female sex partners. Cofactors that increased risk by possibly contributing to progression of genital HPV infection were initiating oral contraceptive use before age 15 and having acquired more than three other sexually transmitted diseases. Past and current smokers were at a slightly higher risk compared to nonsmokers. Although other studies have identified risk factors, few have identified the relative risk of these factors.

Risk factors for invasive cervical cancer in Latino women

Most invasive cervical cancer research in the United States has been conducted on non-Latino-White (NLW) and African-American women. Incidence, mortality, stage at diagnosis and survival indicators for invasive cervical cancer in Latino women in California are compared to NLW and African-American women. A model is presented which depicts structural, behavioral, genetic and biological risk factors for invasive cervical cancer. A literature review of risk factors and their association with invasive cervical cancer was conducted using MEDLINE and PsychINFO databases to determine if ethnic differences in risk factors explain observed differences in morbidity and mortality. Latino women experience a significantly higher incidence and mortality associated with invasive cervical cancer than NLW women. The review of risk factors found that rate differences of cervical cancer screening, early detection and human papilloma virus (HPV) type-specific infection explain much of the disparity in disease burden. Further research must clarify if ethnic differences exist in risk factors associated with ethnic variation in HPV-type prevalence in both cases and their sexual partners, in host immune responses, and multiparity.

The abnormal Papanicolaou smear

Despite its limitations, the Pap smear is a widely accepted, powerful screening technique for cellular abnormalities of the cervix. Abnormal Pap smears are found in 1% to 5% of the screened population, depending on the population characteristics. It is therefore important for all clinicians caring for women to be familiar with the principles of Pap smear screening, its strengths and weaknesses, the terminology used to interpret results, and the options for appropriate response to an abnormal smear. High-grade lesions require colposcopic examination and treatment; low-grade lesions require colposcopic examination and either treatment or close follow-up; atypical smears require some response, either repeated cytology or further investigation; glandular lesions require colposcopic examination and investigation of the endocervix. A tremendous amount of research is going on to assess the safest, most cost-effective approach to the detection, evaluation, and management of cervical epithelial lesions. It can be expected, therefore, that these recommendations will change over the next several years. All physicians providing health care for women should keep abreast of these changes.

Etiology of cervical cancer: current concepts

The data on the etiological factors presented here may enable us to suggest a synergism between the various factors associated with the pathogenesis of cervical cancer. Infection of the cervix by HPV 16/18 may result in persistence of viral DNA. The persistent HPV-DNA undergoes disruption at the E2 region, when integrated into the host genome. The transcriptional products E6 and E7 oncoproteins bind to and cause the degradation of p53 and Rb tumor-suppressor gene products. It is possible that, at that point, other cofactors may be involved in the progression toward a precancerous or cancerous condition. Those cofactors may include cigarette smoking, by introducing co-carcinogens to the tissue or by suppressing the local or systemic immune resistance similar to the effect of depressed immune resistance seen in AIDS or immunosuppression of transplant patients; hormones, by enhancing growth of HPV and transformation of HPV infected cells; low serum vitamin levels leading to decreased tissue resistance; or other infections causing local inflammation and the production of free radicals. CIN develops, leading eventually to cervical cancer.

Invasive squamous-cell cervical carcinoma and combined oral contraceptives: results from a multinational study. WHO Collaborative Study of Neoplasia and Steroid Contraceptives

Data from a hospital-based case-control study collected in 11 participating centers in 9 countries were analyzed to determine whether use of combined oral contraceptives alters risk of invasive squamous-cell cervical cancer. Information on prior use of oral contraceptives, screening for cervical cancer, and suspected risk factors for this disease were ascertained from interviews of 2361 cases and 13,644 controls. A history of smoking and anal and genital warts was obtained, and blood specimens were collected for measurement of antibodies against herpes simplex and cytomegaloviruses, from selected sub-sets of these women, as was a sexual history from interviews of husbands. The relative risk of invasive squamous-cell cervical carcinoma was estimated to be 1.31, with a 95% confidence interval that excluded one, in women who ever used combined oral contraceptives. Risk of this disease increased significantly with duration of use after 4 to 5 years from first exposure, and declined with the passage of time after cessation of use to that of non-users in about 8 years. No sources of bias or confounding were identified that offered plausible explanations for these findings. The strength of these results, and their consistency with those from other studies, suggest that a causal relationship may exist between use of combined oral contraceptives and squamous-cell cervical carcinoma. Women who have used these products for 4 or more years, and who most recently used them within the past 8 years, should receive high priority for cervical cytologic screening.

Abnormal cervical cytology in adolescents: a literature review

This article reviews the literature on the subject of cervical cytological abnormalities in teenagers, defined as a Papanicolaou (Pap) smear result more severe than inflammation. There is discussion of the increasing prevalence of this problem in adolescents. Behavioral and biologic risk factors are examined. The role of the human papillomavirus, widely believed to be the etiologic agent, is addressed. Atypia, its relationship to cervical malignancies, and its management are reviewed. The possible role of the human immunodeficiency virus in the increasing prevalence of cytological abnormalities in teens is considered.

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.

Oral contraceptive use and the incidence of cervical intraepithelial neoplasia

OBJECTIVE

Our objective was to examine the relationship between oral contraceptive use and the incidence of cervical intraepithelial neoplasia.

STUDY DESIGN

In a prospective follow-up study of 6622 women participating in the Second Tromsö Study conducted in 1979 and 1980 in Tromsö, Norway, women aged 20 to 49 years answered a questionnaire regarding their smoking history, dietary habits, alcohol consumption, and oral contraceptive use. They were then followed for 10 years with data from the Pathology Registry of the University Hospital.

RESULTS

The age-adjusted incidence rate of cervical intraepithelial neoplasia was 897 per 100,000 person years among noncurrent and 1295 per 100,000 person years among current oral contraceptive users as of 1979. After adjusting for age, marital status, smoking, and frequency of alcohol intoxication the relative rate for current users was 1.5 (95% confidence interval 1.1 to 2.1), and the relative rate for past users was 1.4 (95% confidence interval 1.0 to 1.8), as compared with those who had never used oral contraceptives before 1979.

CONCLUSION

These findings support the hypothesis that the occurrence of cervical intraepithelial neoplasia is increased by oral contraceptive use.

Case-control study of risk factors for cervical neoplasia in Denmark. II. Role of sexual activity, reproductive factors, and venereal infections

Sexual, reproductive and venereal risk factors for cervical neoplasia were investigated in a population-based case-control study of 586 women with histologically verified, cervical squamous-cell carcinoma in situ, and 59 women with invasive squamous-cell cervical cancer, diagnosed from 1985 to 1986 in Copenhagen. Cases were identified from the computerized Danish Cancer Registry. An age-stratified control group (n = 614) was drawn at random from the female population in the study area by means of the Danish Central Population Register. A structured questionnaire was mailed to cases as well as controls. Increasing number of sexual partners exerted a significant effect on the risk both for carcinoma in situ, and invasive cancer, independently of age at first intercourse and other potential confounders. Conversely, the association with early age at first intercourse became statistically insignificant after allowance for other risk factors, although an increasing risk was still observed with decreasing age at sexual debut. Early age at first episode with genital warts was a significant risk factor for carcinoma in situ, perhaps indicating a possible increased susceptibility of the cervix epithelium during adolescence. A history of genital warts was a good predictor of risk for carcinoma in situ, whereas a history of previous gonorrhea was associated with an increased risk for invasive carcinoma. Women with multiple births had a significantly increased adjusted risk, especially for carcinoma in situ, although some association was also observed with invasive cervical cancer. The study supports the hypothesis of cervical neoplasia being a sexually transmitted disease, and that carcinoma in situ and invasive cervical carcinoma, to a high degree, have similar patterns of risk factors.

Risk factors for cervical intraepithelial neoplasia

To evaluate risk factors for cervical intraepithelial neoplasia (CIN), data were collected in a case-control study based on 366 patients (58 with CIN class 1, 70 with CIN class 2, and 238 with CIN class 3) and 323 control subjects with normal cervical smears interviewed on selected days at the same screening clinics where cases had been identified. No relationship emerged between indicators of socioeconomic status (education and social class) and risk of mild/moderate (considered together) and severe dysplasia. A total of 55 (43%) patients with CIN class 1 or 2, 107 (45%) patients with CIN class 3, and 94 (29%) controls were current smokers. The corresponding relative risk (RR) estimates for current versus never smokers were 1.9 (95% confidence interval [CI] 1.2 to 3.0) for patients with CIN class 1 or 2 and 2.5 (95% CI 1.7 to 3.6) for patients with CIN class 3, and the risk increased with the number of cigarettes smoked per day. No relationship was observed between oral contraceptive use, parity, spontaneous or induced abortions and the risk of CIN, but patients tended to report earlier age at first birth than control subjects. Compared with women reporting their first birth before the age of 20 years, the risk estimates were 0.5 and 0.4, respectively, for patients with CIN 1 or 2 and patients with CIN 3 in women reporting first birth at 20 to 24 years of age. The risk estimates were 0.5 and 0.6 for those reporting their first birth at age 25 or later, but the trends in risk were not statistically significant. The number of sexual partners was directly associated with the risk for both histopathologic subgroups. Compared with women reporting no intercourse or their first intercourse after 22 years of age, women with first intercourse before the age 18 had a RR estimate of CIN class 1 or 2 of 2.3 and of CIN class 3 of 2.4, with the trends in risk being statistically significant. This study confirms considerable similarities in the epidemiology of mild/moderate and severe cervical dysplasia. In addition, it suggests consistency between the epidemiology of intraepithelial and invasive cervical neoplasia for risk factors that are likely to act on one of the first stages of the process of carcinogenesis (i.e., indications of sexual habits) but differences for hormone-mediated factors (i.e., reproductive variables or oral contraceptives).

The health consequences of smoking. Cancer

Smoking has now been identified as a definite cause of cancer at many sites (Table 2). Of all cancers in the United States, 30% could be prevented if cigarette smoking were eliminated. Organs in direct contact with smoke--the oral cavity, esophagus, lung, and bronchus--are at the greatest risk of malignancy among smokers. As many as 90% of these cancers are attributable to smoking. Organs and tissues distant from smoke are also at some increased risk. Among smokers, rates of cancer of the cervix, pancreas, bladder, kidney, stomach, and hematopoietic tissue are increased 50% to 200% over rates in nonsmokers. Risk of cancer at all sites increases with increasing exposure to cigarette smoke. Cigarette smoke contains potent carcinogens that influence carcinogenesis at both early and late stages. These carcinogens can interact with other exposures, such as alcohol, to synergistically increase the risk of cancer. The adverse carcinogenic effects of cigarette smoking, however, can be reduced for all smokers if tobacco use is stopped. The prevalence of smoking among the US population as a whole has declined from 40% in 1965 to 29% in 1987. This progress against the epidemic of tobacco use has already produced a decrease in the occurrence of the most common tumor among men, lung cancer. Unfortunately, the decline in smoking prevalence and cancer incidence has not occurred equally across US populations. Death rates of lung cancer in women continue to rise, and, based upon current smoking patterns, these rates will continue to increase into the next century. The challenge to physicians and public health workers is compelling and immediate: Abstaining from smoking is the single most effective way to reduce an individual's risk of cancer.

The relationship between menarche and sexual, contraceptive, and reproductive life events

Relationships between menarche and sexual, contraceptive, and reproductive life events were investigated by structured interviews of 585 Danish women, aged 15-54 years. Data were analyzed by multivariate test statistics. The trend toward an earlier menarche was confirmed. No association was found between menarche and social class. Women with early menarche had an earlier coital debut. After correction for coital debut, no association was observed between menarche and coital frequency, number of sexual partners, or use of oral contraceptives. Menarche was not associated with number of births, spontaneous or induced abortions, or frequency of ectopic pregnancies. The results suggest that the predictive value of the menarche for sexual and contraceptive life events is conditioned primarily by the association between menarche and coital debut.

Case-control study of risk factors for cervical intraepithelial neoplasia in young women

A case-control study of 497 women under age 40 diagnosed with cervical intraepithelial neoplasia (CIN) and 833 controls was done in the London area between 1984 and 1988 to examine whether known risk factors for invasive cervical cancer produced similar risks for CIN of different grades in young women. Cases of CIN III had a risk profile similar to that seen for invasive disease whereas CIN I cases were similar to the controls in all risk factors examined except a history of genital warts. Cases of CIN II were intermediate between the two. Among several indicators of sexual and reproductive behaviour, age at first childbirth and a history of multiple sexual partners were the strongest risk factors for CIN II and CIN III. Smoking had a strong and independent effect on the risk of CIN II and CIN III, but had only a limited effect for CIN I. Use of oral contraceptives was widespread in cases and controls, but length of use of oral contraceptives was not found to be a risk factor. A small protective effect of barrier contraception was observed.

Oral contraception: risks and benefits

Data on the risks and benefits of using the oral contraceptive continue to accumulate. Because of continuing changes in the formulation and dosage of both the estrogens and progestins, the medical community must constantly re-evaluate all older data when considering current risk/benefit ratios. The changes in pill formulation have led to increased acceptability with a reduction of both nuisance and serious long-term side effects. The risks must be balanced against the major contraceptive and non-contraceptive benefits that are provided by the pill. Although both the benefits and risks have been documented in the literature, both the physician and the patient are being overwhelmed by press reports stressing mainly the negative aspects of the pill. It is incumbent on all physicians to periodically review the sources and validity of all medical reports on the pill. While the benefits of the pill outweigh the risks, the physician must be constantly aware of the changing world literature in order to optimize his/her prescribing patterns.

Differences in biologic maturation, sexual behavior, and sexually transmitted disease between adolescents with and without cervical intraepithelial neoplasia

Because several cofactors may influence the development of cervical intraepithelial neoplasia (CIN) in young women, we compared differences in behaviors (sexual activity, contraception, and cigarette use), sexually transmitted disease (STD) infection rates (Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, and herpes simplex virus), and cervical maturation (age of menarche and percentage of cervical ectopy) in groups of sexually active female adolescents with and without CIN. Those with CIN were compared with three non-CIN groups: (1) teenagers who were referred to a teen colposcopy clinic but had no evidence of CIN (high-risk group), (2) teenagers seen at a gynecology clinic without STD symptoms (asymptomatic group), and (3) teenagers seen at the gynecology clinic with STD symptoms (symptomatic group). The percentage of cervical ectopy was measured by colpophotography. Subjects with CIN had more lifetime sexual partners than the asymptomatic group (p less than 0.001) and were more likely to smoke cigarettes than either gynecology clinic group (p less than 0.01). No differences in behaviors existed between the CIN and high-risk groups. The mean age of menarche in those with CIN was 1 year older than all three non-CIN groups (p less than 0.05), and those with CIN had a greater area of ectopy than those without CIN (p less than 0.02). Those with CIN were more likely to have a past or present history of C. trachomatis infection than the two gynecology clinic groups; no difference was found between the CIN and high-risk groups. We conclude that cofactors such as smoking, sexual promiscuity, and C. trachomatis infection may influence cervical vulnerability. However, cervical biologic immaturity is an important risk factor for development of CIN in adolescent girls.

Risk factors for cervical cancer in Greenland and Denmark: a population-based cross-sectional study

The incidence of cervical cancer in Greenlandic women aged 20-39 years is nearly 6 times higher than in Danish women of the same age. Possible determinants of cervical cancer incidence were investigated in a population-based cross-sectional study. From Nuuk (Greenland) and Nykøbing Falster (Denmark) a sample of 800 women aged 20-39 years was drawn at random. A total of 586 and 661 women were studied in Greenland and Denmark, respectively. All underwent a personal interview. In Greenland, 13% of the women reported first intercourse before the age of 14 in contrast to 3.5% in Denmark, and nearly 85% of the Greenlanders had their sexual debut before the end of the 16th year of age whereas this applied to only 45% of the Danish women. The prevalence of women with 0-1 lifetime sexual partner was 20.4% in Denmark, and only 1.7% in Greenland. In contrast, 53.2% of the Greenlandic women reported more than 20 partners and 22.4% more than 40 partners. The corresponding figures for Denmark were 3.6% and 0.3%, respectively. In Greenland the most common contraceptive method was the use of intra-uterine devices (73.6%), whereas, in Denmark, oral contraceptive use was most frequent (87.9%). Few Greenlanders had ever used "barrier" contraceptives (diaphragm: 1.4%; condom: 18.1%) compared to Denmark (diaphragm: 10.1%; condom: 53.9%). As many as 87.4% were current smokers in Greenland (Denmark: 53.6%) and 5.6% claimed to have never smoked, whereas this applied to 35.3% in Denmark. The indications of a higher sexual activity (multiple partners, early age at first intercourse) in Greenland compared to Denmark are in line with the observed higher rates of sexually transmitted diseases and with the hypothesis that differences in cervical cancer incidence between Greenland and Denmark are determined by aspects of sexual background.

Papanicolaou smear: an update on classification and management

Current research has caused us to reconsider the factors associated with cervical dysplasia. New recommendations for the collection of cervical specimens, interpretation of the Papanicolaou smear, and patient management have also evolved. Research findings and a discussion of the classifications to be used when reporting the results of the smear are updated in this paper. Interpretation and nurse-practitioner management of the normal and mildly abnormal Pap result is included.

Cancer of the breast and reproductive tract in relation to use of oral contraceptives

Effects of oral contraception on cancers of the female breast and reproductive tract are critically reviewed from human studies reported since 1980. The cumulative risk of breast cancer through 59 years of age appears to bear no relationship to oral contraceptive (OC) use whatsoever. Studies restricted to women under age 45, however, raise concern about a possible adverse effect from OC use before a first-term pregnancy. A duration-related protective effect against endometrial cancer occurs from use of combined OCs. The risk is reduced by about 40% with 2 years of use, and by about 60% with 4 or more years of oral contraception. Oral contraception in excess of 3 years protects against ovarian cancer. Four years of use confers a 50% reduction in risk and 7 or more years of use confers a 60%-80% reduction in ovarian cancer risk. Studies of cervical dysplasia and carcinoma in situ suggest elevated risks with 2 or more years of OC use, although results are difficult to interpret in view of numerous factors that might distort the findings. The risk of invasive cervical cancer appear to be unaffected by up to 5 years of oral contraception. Beyond this, there is evidence suggesting an elevated risk which approaches a 2-fold increase at 10 years of use. Cancers of the vagina and fallopian tube are extremely rare. Their risks have yet to be characterized in relation to oral contraception.

Carcinoma of the cervix and smoking

There is considerable evidence from epidemiologic and clinical studies that cigarette smoking is associated with the risk of cervical cancer. Definitive clarification of whether this association is causal will likely have to await definitive identification of the sexually transmitted agent which is probably the most important cause of cervical cancer. Only then will it be possible to clarify the contributions of risk factors with weaker associations with cervical cancer, such as cigarette smoking and socioeconomic status.

Carcinoma of the cervix and oral contraceptives: epidemiological studies

The relationship between squamous carcinoma of the cervix and oral contraceptive use has been examined in a substantial number of epidemiological studies. On balance there is reasonably convincing evidence that prolonged oral contraceptive use slightly increases the risk of the disease, but some doubt remains as to whether or not confounding factors have been controlled adequately in the studies reporting positive findings. The data are too few at present for any reasoned comment to be made about the possible relationship between oral contraceptives and adenocarcinoma of the cervix.

Future trends in cervical cancer

The identification of the close association of certain types of human papillomavirus with the development of cervical cancer should lead to an extensive revision of appropriate health policies. Having taken into account the drawbacks inherent in the existing data (stemming from the use of varying nomenclature, diagnostic methods and reliability, registration and screening practices) it is possible to conclude that the incidence of HPV infections, all premalignant and malignant stages of cervical cancer are, or will soon be, increasing in several countries. This rate of increase is fastest for the younger age groups and is despite the introduction of various forms of screening. These trends therefore indicate an urgent need to adopt policies to avert an unnecessary increase in fatalities due to cervical cancer. It is therefore recommended to: (1) establish a routine diagnostic method which can identify either the type of HPV present or the lesions which are progressing; (2) determine the incidence of HPV infections in the general population; (3) disseminate to medical personnel, teachers, and other members of society existing knowledge concerning the dangers associated with this virus and relevant to preventing its further spread; (4) introduce an effective population screening campaign for all sexually active women, preferably involving a yearly examination at a colposcopy clinic; (5) intensify basic and applied HPV research, especially that which could lead to a deeper understanding of viral transmission and infection, identification of cofactors which promote cervical lesion progression, or to the production of a vaccine.

Sexual and reproductive life events in relation to duration of oral contraceptive use

In order to disclose differences between users and non-users of oral contraceptives (OC), 620 women aged 15-54 were invited to participate in an in depth interview about sexual, contraceptive, and reproductive life events. Of the 585 women who participated, 459 were consecutive gynecological in- or outpatients, and 126 were selected from visitors in general practice. Data was analysed by multivariate test statistics. After correction for present age and social class, the duration of use of OC (DOC) among women 15-34 years of age correlated negatively to age at menarche and coital debut and positively to number of sexual partners, oral-genital sexual practice, and number of pelvic inflammatory diseases. Among women over 35, DOC was positively associated only to cigarette smoking. No correlation was found to coital frequency (whether earlier, present or during pregnancy or menstruation), number of births and abortions, or to social classification. In epidemiological research on benefits and risks of oral contraceptives, confounding influence of one or more variables is of crucial importance. The present findings point at sexual and life-style habits as potential confounders in the study of OC and associated diseases.

DNA viruses and human cancer

This review examines some of the evidence which aetiologically implicates various DNA viruses (primarily papillomavirus, hepatitis B virus and Epstein-Barr virus) in certain human cancers (cervical carcinoma, primary liver cell carcinoma, Burkitt's lymphoma and nasopharyngeal carcinoma, respectively). The evidence includes: presence of viral DNA, RNA and proteins in tumours (and cell lines derived from them); occurrence of viruses with apparently different oncogenic potential; their ability to transform cell lines in vitro or cause tumours in animals; epidemiological and serological data. Factors which affect the progression to cancer are briefly considered as they illustrate that there are several stages in tumorigenesis. These factors include the immune system, irradiation, presence of other viruses or carcinogens and treatment. The lack of a single unique characteristic which defines a transformed cell would be expected from the multistep hypothesis and is related to the possible virus-cell interactions that can occur. These form a continuous spectrum ranging from productive infection of a permissive cell, through infection of a non-permissive cell, to the inability of a virus to infect a cell. This spectrum may reflect the absence of increasing numbers of cellular functions necessary for productive virus infection, with cell transformation occurring as a rare type of abortive infection. The evidence, especially for human papillomavirus, indicates that it is quite probable that particular DNA viruses are the causative agents for certain human cancers. Even so other factors can play decisive roles in tumorigenesis. Final aetiological proof will only be obtained when an anti-virus vaccine eradicates one form of human cancer.

A comparison of physician and patient reports of Pap smear histories

We describe the level of agreement between patients and their physicians with respect to their use of the Pap smear, the symptoms present, and the smear results. The data derived from a case-control interview study of 181 newly diagnosed invasive squamous cell cervical cancer cases and 905 age-matched controls, a second case-control interview study of 250 cases of cervical dysplasia and 500 age-matched controls, and the medical records of attending physicians for all patients. Cases and controls in both studies reported more smears over the previous 5 years than their medical records indicated; also patients reported their last smear as more recent than noted in physician files. Cancer cases were somewhat more accurate on frequency and timing of smears than the other patient groups. Patients tend to report more symptoms at interview than recorded in their files. Disagreements on smear results were probably because of differences in terminology, especially in distinguishing invasive from pre-cancerous conditions; cancer cases tended to report some dysplasias as cancer, but the controls in both studies under-reported dysplasia. If high physician response rates can be obtained, we would prefer to use physician records as the basis of evaluation of screening programs, especially when accurate dating of screening events is required. However it is less clear whether physician records are to be preferred, if the evaluation is to take symptoms into account.

Cervical cancer screening practices among older women: results from the Maryland Cervical Cancer Case-Control Study

Considerable evidence shows a large proportion of older women have either never had a Pap test or have significant gaps in their history of cervical cancer screening. Differences in health care utilization patterns by age, cohort differences in use of medical subspecialities, and provider reluctance to perform cancer screening within the general medical care encounter have been suggested as reasons for underscreening. Our study conducted in 1985 documents prior health care utilization patterns of 153 cases of Maryland women with invasive cervical cancer compared with a matched control group. Analysis within three age groups showed that cases were significantly less likely to have ever had a Pap test or to receive regular Pap testing, primarily due to differences in medical care utilization patterns. Never having an obstetrician-gynecology visit, a recent (less than 3 years) internist visit, or not having any out-patient visit were significant risk factors. Other risks included older age at first Pap test, reporting not being told to have routine Pap tests, and not using contraceptives. In a multiple logistic regression analysis, recent out-patient visits and lifetime use of an obstetrician-gynecologist remained significant after adjusting for age interactions with recent Pap test history, underscoring the importance of medical care utilization patterns for screening of cancer of the uterine cervix among the elderly.

Low prevalence of cervical intraepithelial neoplasia among Egyptian females

Analysis of 4458 patients evaluated by cytology at the Department of Obstetrics and Gynecology, Kasr El-Einy Hospital, Cairo University, during the years 1981 to 1985 revealed that only 1.07% of these women had abnormal cytology. The prevalence rate for cervical intraepithelial neoplasia (CIN) was remarkably low, corresponding to 3.59/1000 for CIN grade I, 2.28/1000 for CIN II, and 1.16/1000 for CIN III. The mean age for CIN was 44.23 years while that for cervical cancer was 54.32. This low prevalence rate of CIN among Egyptian females, together with the late onset of the disease in comparison with other populations, calls for further study of the epidemiologic characteristics of this low-risk community.

Use of oral contraceptives and risk of invasive cervical cancer in previously screened women

Within the context of a larger hospital-based case-control study carried out to assess the efficacy of cervical cancer screening, the possible association between oral contraceptives and risk of invasive cervical cancer has been studied as well. Because in the GDR cytological screening is an integral part of the gynaecological basic care, only a few women reported oral contraceptive use but had no Pap-smears in that study. Thus, the analysis was confined to those 129 cases and 275 controls who had at least one screening Pap-smear in their history and were below the age 55. The significantly increased relative risks for users decreased after adjustment for factors of sexual behaviour and interval since last Pap-smear but remained statistically significant or at borderline significance for some categories of usage. This concerns, in particular, long-term use (7+ years) and early onset of use (less than or equal to 24 years) with relative risks of 1.8 and 3.0, respectively.

Workshop on guidelines to the epidemiology of weak associations. Confounding

The magnitude of confounding is examined in nine case studies of two "weak" relationships: between artificial sweeteners and bladder cancer, and between oral contraceptives and cervical dysplasia. Confounding had little or no influence on the results of any published study. The responsible epidemiologist must always consider the possibility of confounding, no less when associations are weak than when they are strong. Identification of potentially confounding variables is an integral part of good epidemiologic practice. Rarely, however, does confounding itself, especially from unidentified sources, live up to its reputation for introducing seriously spurious associations. An investigator is more likely to be led astray by undetected biases than by pure confounding.

A new era in contraceptive counseling for early adolescents

In a new era of increased concern about sexually transmitted diseases, the ethical focus of contraceptive counseling for the early adolescent has changed. A discussion of the ethical aspects of contraceptive counseling is included to emphasize contemporary concerns about informed consent and safe contraceptive methods.

Long-term use of oral contraceptives and risk of invasive cervical cancer

To evaluate the relationship between use of oral contraceptives and risk of invasive cervical cancer, a case-control study involving 479 patients and 789 population controls was undertaken in 5 geographic regions of the US. Initially, the relationship was obscured by confounding variables, particularly the interval since last Pap smear. Control for this variable as well as for sexual and sociodemographic factors revealed an RR of 1.5 overall, with long-term users (5 or more years) being at a 2-fold higher risk than non-users. Pill associations prevailed for both adenocarcinomas and squamous-cell tumors, and risks were highest for those using pills containing high estrogen potencies. In addition, there was some evidence that pill associations were most pronounced among women who had never used barrier methods of contraception or who had histories of genital infections, suggesting that oral contraceptives may act as co-carcinogens with transmissible agents. Our findings provide further evidence that long-term use of oral contraceptives may have a carcinogenic effect on cervical epithelium, but emphasize the need for careful evaluation of confounding influences.