Smoking as a risk factor in cancer of the cervix: additional evidence from a case-control study

Impact of organized and opportunistic Pap testing on the risk of cervical cancer in young women - A case-control study from Finland

OBJECTIVE

Effectiveness of organized cervical cancer screening has been shown in several studies. However, screening among women aged <25years has been suggested to have little or no impact on the risk of cervical cancer. Also the significance of opportunistic testing in preventing cervical cancer is unclear. The aim of this study was to clarify the effect of opportunistic testing and organized screening on the risk of cervical cancer among young Finnish women.

METHODS

In the Finnish Cancer Registry there were 284 cervical cancer cases diagnosed and tested below the age of 40 in 2004-2009. Screening histories and data on opportunistic testing for these women and their 1698 age-matched controls were derived from databases of the Mass Screening Registry and The National Institute for Health and Welfare from 1997 onward. OR's and 95% CI's for the association of cervical cancer diagnosis and participation in organized screening and opportunistic testing were estimated using unconditional logistic regression. Results were corrected for self-selection bias and attendance rate.

RESULTS

Among women aged under 25, OR of cervical cancer for any Pap test taken 0.5-5.5years before diagnosis was 1.25 (95% CI 0.46-3.43). Attending only organized screening at age 25-39 resulted in OR 0.52 (0.36-0.77), attending only opportunistic testing in OR 0.86 (0.60-1.25) and attending both in OR 0.48 (0.29-0.79).

CONCLUSION

Opportunistic testing showed no clear additional benefit on preventing cervical cancer. The study also supports findings on a smaller effect of screening in younger age groups.

Association between smoking and size of anal warts in HIV-infected women

While the association between smoking and human papillomavirus infection, cervical cancer, and anal cancer has been well studied, evidence on the association between cigarette smoking and anal warts is limited. The purpose of this study was to investigate if cigarette smoking status influences the size of anal warts over time in HIV-infected women in a sample of 976 HIV-infected women from the Women's Interagency HIV Study (WIHS). A linear mixed model was used to determine the effect of smoking on anal wart size. Even though women who were currently smokers had larger anal warts at baseline and slower growth rate of anal wart size after each visit than women who were not current smokers, there was no association between size of anal wart and current smoking status over time. Further studies on the role of smoking and interaction between smoking and other risk factors, however, should be explored.

Smoking behavior in women with locally advanced cervical carcinoma: a Gynecologic Oncology Group study

OBJECTIVE

The purpose of this study was to assess cigarette use and environmental smoke exposure in women with cervical cancer.

STUDY DESIGN

Smoking behavior was recorded prospectively in a clinical trial of women with locally advanced cervical carcinoma.

RESULTS

Of 315 participants, 133 women (42%) were current smokers; 72 women (23%) were former smokers, and 110 women (35%) were never smokers. Current smokers began smoking earlier (16 vs 18 years; P = .009), for more years (29 vs 24 years; P = .005), and in greater amounts (20 vs 11 cigarettes/d; P < .001) than former smokers. Active smokers lived more often with another smoker (63.3%), compared with former smokers (35.0%; P < .001) or never-smokers (28.7%; P < .001). Agreement between self-report and urine cotinine level was high (kappa = 0.872; P < .001). A significant decrease in cotinine level during treatment occurred in 5.2% of current smokers.

CONCLUSION

Prevalence of smoking and tobacco consumption was twice that of the North American female population. Few smokers quit or decreased consumption during treatment.

Cutaneous papillomatosis and carcinomatosis in the Western barred bandicoot (Perameles bougainville)

A progressive wart-like syndrome in both captive and wild populations of the Western barred bandicoot (WBB) is hindering conservation efforts to prevent the extinction of this endangered marsupial. In this study, 42 WBBs exhibiting the papillomatosis and carcinomatosis syndrome were examined. The disease was characterized by multicentric proliferative lesions involving cutaneous and mucosal surfaces, which were seen clinically to increase in size with time. Grossly and histologically the smaller skin lesions resembled papillomas, whereas the larger lesions were most commonly observed to be squamous cell carcinomas. Large amphophilic intranuclear inclusion bodies were observed in hyperplastic conjunctival lesions of 8 WBBs under light microscopy. Conjunctival lesions from 2 WBBs examined using transmission electron microscopy contained a crystalline array of spherical electron-dense particles of 45-nm diameter, within the nucleus of conjunctival epithelial cells, consistent with a papillomavirus or polyomavirus. Conjunctival samples from 3 bandicoots that contained intranuclear inclusion bodies also demonstrated a positive immunohistochemical reaction after indirect immunohistochemistry for papillomavirus structural antigens. Ultrastructural and/or immunohistochemical evidence of an etiologic agent was not identified in the nonconjunctival lesions examined. Here we describe the gross, histopathologic, ultrastructural, and immunohistochemical findings of a papillomatosis and carcinomatosis syndrome recently identified in the WBB.

Smoking is an independent risk factor for oncogenic human papillomavirus (HPV) infections but not for high-grade CIN

BACKGROUND

Recent evidence implicates smoking as a risk factor for cervical cancer (CC), but the confounding from high-risk human papillomavirus (HPV) infections is not clear.

OBJECTIVES

To analyse the role of smoking as an independent predictor of CIN2+ and HR-HPV infections in a population-based prospective (NIS, New Independent States of former Soviet Union) cohort study.

STUDY DESIGN AND METHODS

A cohort of 3,187 women was stratified into three groups according to their smoking status: (i) women who never smoked; (ii) those smoking in the past; and (iii) women who are current smokers. These groups were analysed for predictors of (a) HR-HPV; (b) high-grade CIN, and (c) outcome of HR-HPV infections and cytological abnormalities during prospective follow-up (n = 854).

RESULTS

The three groups were significantly different in all major indicators or risk sexual behaviour (or history) implicating strong confounding. There was no increase in HSIL/LSIL/ASC-US cytology or CIN1+/CIN2+/CIN3+ among current smokers. Only few predictors of HR-HPV and CIN2+ were common to all three groups, indicating strong interference of the smoking status. There was no difference in outcomes of cervical disease or HR-HPV infections between the three groups. In multivariate model, being current smoker was one of the five independent predictors of HR-HPV (P = 0.014), with adjusted OR = 1.52 (95%CI 1.09-2.14). In addition to age, HR-HPV was the only independent predictor of CIN2+ in multivariate model (OR = 14.8; 95%CI 1.72-127.31).

CONCLUSIONS

These data indicate that cigarette smoking is not an independent risk factor of CIN2+, but the increased risk ascribed to smoking is mediated by acquisition of HR-HPV, of which current smoking was an independent predictor in multivariate model.

The effect of female tobacco smoking on IVF outcomes

BACKGROUND

Cigarette smoking is widely believed to be associated with decreased fecundity in naturally conceiving populations; however, the effect of female smoking on pregnancy outcomes in patients undergoing IVF is unclear.

METHODS

A retrospective analysis of 389 consecutive patients undergoing first cycle IVF was performed. Outcomes of peak estradiol (E(2)) levels, log mean ovarian volume, number of oocytes retrieved, oocyte maturity in ICSI, fertilization rate, cleavage rate, embryo quality, percentage of high-quality embryos, pregnancy and live birth were assessed in patients reported as never smokers, past smokers and current smokers. Potential confounding variables evaluated included day 3 FSH, number of oocytes retrieved, embryo quality, caffeine and alcohol consumption. The population was also stratified by female age (<35 and >or=35 years).

RESULTS

A total of 9.3% of our patients reported current smoking and 12.1% reported a history of smoking. Smoking status did not significantly affect pregnancy outcome, live birth rate or any other indicated outcome.

CONCLUSIONS

A total of 21.4% of IVF patients in this study had past or present exposure to cigarette smoking with no measurable effect on IVF outcome.

Epidemiology of substance use disorders in women

Significant gender differences exist in the prevalence of substance use disorders in the United States. There is a trend among boys and girls aged 12 to 17 years toward comparable rates of use and initiation for alcohol, cocaine, heroin, and tobacco. If this trend continues, over time there may be a narrowing of the male-to-female prevalence ratios of substance abuse in the older age groups. This possibility is particularly disturbing because women have a heightened vulnerability to medical, physical, mental, and social consequences of substance use. Women also carry additional unique risks during pregnancy because of the effect on neonates. In addition, they have certain gender-specific cancer risks. Given this and the declining age of initiation of substance use in women, prevention and treatment efforts especially geared toward women (eg, education of all medical and paramedical staff, screening in primary care clinics, detection of drug use early in pregnancy or before conception, brief interventions and treatment programs that integrate women's needs) are exceedingly important to stop and ultimately reverse this growing trend.

Family physicians' knowledge of risk factors for cervical cancer

BACKGROUND

A woman's risk for cervical cancer has been used by physicians to guide the initiation and frequency of a Pap smear. The aim of this study was to determine family physicians' knowledge of risk factors for cervical cancer and perceived importance of risk in screening women.

METHODS

The self-administered questionnaire was mailed to 5000 randomly selected active members of the American Academy of Family Physicians (AAFP).

RESULTS

Data from 2748 usable questionnaires indicated the mean number of risks considered for cervical cancer was 4.5. Physician's age and the number of reported risks were inversely correlated (p = 0.0001). Female physicians reported significantly more risk factors than male physicians (p = 0.05). The number of Pap smears performed per month was positively correlated with the number of risk factors reported (p = 0.001). Only 10% of the physicians indicated that they perform a Pap smear at the same interval regardless of the risk of the woman.

CONCLUSIONS

This sample of family physicians has a limited understanding of the risk factors for cervical cancer. This was true regardless of the age, gender, training, race, geographic location, or practice setting of the responding physician. Yet the usual practice of screening for cervical cancer reported by these physicians would suggest that knowledge and use of risk factors would be a critical aspect of screening for cervical cancer.

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.

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.

Effect of organised screening on cervical cancer incidence and mortality in Finland, 1963-1995: recent increase in cervical cancer incidence

A nation-wide screening programme for cervical cancer started in Finland gradually from 1963 onwards. By the beginning of the 1990s, there had been a decrease of 80% both in the age-adjusted incidence of and mortality from cervical cancer. To describe the recent patterns in cervical cancer incidence and mortality and evaluate their differentials in relation with the organised screening activities, we have updated the material on the cervical cancer incidence and mortality as well as mass-screening activities up to the year 1995. Based on the files of the Finnish Cancer Registry, there is a striking increase of about 60% in the incidence of cervical cancer during the last 4 years of the study period among women below 55 years of age. The mortality rates are still decreasing. There is no overall decrease over recent years in the coverage of the programme invitations or smears taken. Incidence of invasive cancer and of moderate and severe dysplasia as detected in mass screening have increased. As to the interpretation, changes in the risk factors, such as in sexual behaviour and smoking habits, over the decades might partly explain increasing trends in cervical cancer incidence. As the change in incidence was relatively abrupt, inadequacies or changes in the effectiveness in the screening programme, particularly among young women, may also have contributed. Expanding the coverage of and attendance in the pap-screening programme among women in young target ages would still be effective. Increasing emphasis on quality assessment in screening is also needed.

Smoking and hormone-related disorders

Through its antiestrogenic effect, cigarette smoking is linked to a variety of hormone-related disorders, both benign and malignant. Diseases that depend on this hormone for growth and development tend to be less common among smokers, such as endometrial cancer and uterine fibroids. Some normal, estrogen-dependent physiologic processes are affected by smoking, making osteoporosis and premature menopause more common among women who smoke. In other disorders, the link between sex hormone levels, cigarette smoking, and disease development is less clear.

Epidemiology and biology of cervical cancer

Worldwide, cancer of the cervix is the second leading cause of cancer death in women: each year, an estimated 500,000 cases are newly diagnosed. Among populations, there are large differences in incidence rates of invasive cervical cancer: these reflect the influence of environmental factors, screening Papanicolaou (Pap) tests, and treatment of pre-invasive lesions. The high-risk human papillomavirus (HPV) subtypes 16, 18, 31, 33, and 51 have been recovered from more than 95% of cervical cancers. We have made great strides in understanding the molecular mechanism of oncogenesis of this virus, focusing on the action of the E6 and E7 viral oncoproteins. These oncoproteins function by inactivating cell cycle regulators p53 and retinoblastoma (Rb), thus providing the initial event in progression to malignancy. Cervical cancers develop from precursor lesions, which are termed squamous intraepithelial lesions (SIL) and are graded as high or low, depending on the degree of disruption of epithelial differentiation. Viral production occurs in low-grade lesions and is restricted to basal cells. In carcinomas, viral DNA is found integrated into the host genome, but no viral production is seen. The well-defined pre-invasive stages, as well as the viral factors involved at the molecular level, make cervical carcinoma a good model for investigating immune therapeutic alternatives or adjuvants to standard treatments.

Detection of human papillomavirus in cervical biopsies of summer camp ROTC cadets with abnormal papanicolaou smears

STUDY OBJECTIVE

Human papillomavirus (HPV) infections may be the most common sexually transmitted disease (STD) among adolescents and young adults. A strong association exists for certain "high-risk" HPV-type cervical infections and subsequent evolution of cervical cancer and its precursor lesions. The objective of this study was to detect HPV in cervical biopsies of reserve officer training corps (ROTC) cadets attending a regional summer camp who had abnormal screening Papanicolaou (Pap) smears and to better define the spectrum of HPV oncogenic risk types for this population. It was hypothesized that HPV would be detected in the majority of cervical biopsies in keeping with the evolving concept of cervical cancer and its precursors as an STD and the central role of HPV in its development.

DESIGN

On arrival for summer military camp training, college women cadets underwent physical examinations that included pelvic examinations for Pap smears. Study participants completed confidential questionnaires after informed consent was obtained. Subjects, who had abnormal Pap smears as defined by reports of atypical squamous cells of undetermined significance (ASCUS) or low- or high-grade squamous intra-epithelial lesions (LGSIL or HGSIL), underwent colposcopic evaluations with cervical biopsies. Subsequently, biopsies were processed for detection of HPV-specific DNA by gel electrophoresis, chemiluminescent oligonucleotide probing, and DNA-RNA hybridization methods after polymerase chain reaction (PCR) amplification.

PARTICIPANTS

All female summer camp enrollees presented to the Madigan Army Medical Center Gynecology Clinic for complete physicals before the onset of the training program and were solicited for study inclusion.

MAIN OUTCOME MEASURES

All colposcopic biopsy specimens were evaluated for the presence of HPV DNA and subtyped if positive.

RESULTS

Representing 42 states, 95% (332) of eligible subjects participated. Mean age was 21.9 years. Racial composition included 70% white, 16% black, 4% Hispanic, 4% Asian, and 6% "other." Eighty-five percent had a history of hetero-sexual activity, with 17.7 years as the mean age at onset. Of the subjects, 12.6% reported a previous diagnosis of a sexually transmitted disease, and 7.8% (26 of 332) had abnormal Pap smears. Of these, colposcopic biopsy results were available for 25 of the 26 abnormal Pap smears. Ninety-six percent (24 of 25) of the colpobiopsies had detectable HPV. Eighty-eight percent (22 of 25) of the subjects with abnormal Pap smears had concurrent abnormal biopsy results. All of these had detectable HPV, confirmed by three different methods, and 29% had dual HPV infection. Sixty percent had "intermediate" or "high-risk" types identified by specific genotyping, 8% had "low-risk" types, and 28% had nontypable HPV.

CONCLUSIONS

The data confirm that abnormal Pap smears in this young adult college population are almost always associated with HPV infection, a significant proportion of it being other than low-risk types. The prognostic significance of type-specific cervical HPV infection still needs to be better defined in relation to potential cofactors and host immune response. However, clinicians who provide primary gynecologic care to adolescents and young adults should be aware of the high correlation between abnormal Pap smears and HPV cervical infection and should follow up the patient with the potential risk in mind.

The epidemiology of cervical carcinogenesis

Epidemiologic and laboratory data suggest that cervical cancer typically arises from a series of causal steps. Each step can be studied separately in the hope of better etiologic understanding and improved cancer prevention. The earliest identified etiologic step is infection of young women with specific types of venereally transmissible human papillomaviruses (HPVs). Cervical HPV infections often lead to low grade squamous intraepithelial lesions (mildly abnormal Pap smears). Human papillomavirus infections and their associated lesions are extremely common among young, sexually active women. The infections typically resolve spontaneously even at the molecular level within months to a few years. Uncommonly, HPV infections and/or low grade lesions persist and progress to high grade lesions. The risk factors for progression are mainly unknown but include HPV type and intensity, cell-mediated immunity, and reproductive factors. Nutritional factors or co-infection with other pathogens may also be involved at this apparently critical etiologic step between common low grade and uncommon high grade intraepithelial lesions. Except for advancing age, no epidemiologic risk factors have been found for the next step between high grade intraepithelial lesions and invasive cancer. At the molecular level, invasion is associated with integration of viral DNA. Based on worldwide research, the steps in cervical carcinogenesis appear to be fundamentally the same everywhere, with a central role for HPV infection. The importance of etiologic cofactors like smoking, however, may vary by region.

Clinical application of HPV typing in cervical cancer

Certain human papaillomavirus (HPV) types are major risk factors for the development of cervical neoplasia. The value of HPV DNA testing in the management of patients with disease and in population screening is a subject of controversy. Since the introduction of molecular biology into the HPV field, there have been rapid advances and improvements in HPV diagnosis. The various molecular diagnostic methods for detection of HPV DNA (dot blot hybridization, Southern blot hybridization, in situ hybridization, Hybrid Capture Test, and polymerase chain reaction; PCR) could be selected by taking into consideration some factors such as characteristics of sample, sensitivity of HPV test and expenses. The HPV DNA testing would be a clinically useful diagnostic method, when used in conjunction with the Pap smear in population screening or in conjunction with cytology and colposcopy to identify the women infected with high-risk HPVs or women who had equivocal cervical lesions. Despite the confusion, a multitude of reports demonstrate that HPV DNA testing has the clinical utility, and future investigations should be directed at more accurately delineating its role in human health care.

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.

Cigarette smoking and human papillomavirus in patients with reported cervical cytological abnormality

OBJECTIVE

To assess the relation between two risk factors for cervical neoplasia: smoking and infection with oncogenic human papillomavirus. It has been suggested that smoking causes a local immunological defect, which could facilitate the infection and persistence of human papillomavirus.

DESIGN

Cross sectional epidemiological study. Completion of a structured questionnaire by the patients, analysis of cervical scrapes for human papillomavirus, and morphological examination of biopsy specimens.

SETTING

Outpatient gynaecological clinic.

SUBJECTS

181 women with a report of cervical cytological abnormality.

MAIN OUTCOME MEASURES

Prevalence of infection with oncogenic human papillomavirus and smoking habits.

RESULTS

Oncogenic human papillomavirus was found in the cervix of 26 (41%) of the 63 women who did not smoke, 22 (58%) of the 38 who smoked 1-10 cigarettes a day, 28 (61%) of the 46 who smoked 11-20 cigarettes a day, and 26 (76%) of the 34 who smoked > or = 21 cigarettes a day. The prevalence of the virus thus increased in accordance with the number of cigarettes smoked (p = 0.001). This relation remained after adjustment for age at first intercourse and lifetime number of sexual partners. Of the 63 non-smokers, 23 had previously smoked at least 10 cigarettes a day at some time. Of these 23 women, 14 (61%) had oncogenic human papillomavirus in their cervix. Of the 40 women who had never smoked at least 10 cigarettes a day, 12 (30%) had the virus. The prevalence of oncogenic human papillomavirus in non-smokers therefore depended on previous smoking habits (p = 0.03).

CONCLUSION

The dose dependent effect of cigarette smoking on the occurrence of oncogenic human papillomavirus favours a causal relation between these risk factors for cervical neoplasia.

Factors influencing the exfoliation of cervicovaginal epithelial cells

OBJECTIVE

Our objective was to investigate the association of smoking and exfoliation of cervicovaginal epithelial cells while controlling for other factors that may potentially influence cell exfoliation (e.g., presence of cervical intraepithelial neoplasia or koilocytes, the use of oral contraceptives, age, and the phase of the menstrual cycle).

STUDY DESIGN

Cervicovaginal lavage specimens and epidemiologic questionnaires were obtained with informed consent from 190 women. The cervicovaginal lavage samples were processed to separate other contaminants. The number of squamous epithelial cells counted was expressed as cells per milliliter of lavage.

RESULTS

Multiple linear regression analysis revealed that the number of exfoliated epithelial cells was significantly higher in smokers (p < 0.01) and also in women with cervical intraepithelial neoplasia (p < 0.05). The other studied variables had no detectable effect.

CONCLUSION

The findings suggest that smoking or the presence of cervical intraepithelial neoplasia may induce an acceleration in the exfoliation of cervicovaginal epithelial cells. This may alter cell maturation and may be a factor in the oncogenic process.

Vaginal microbial flora as a cofactor in the pathogenesis of uterine cervical intraepithelial neoplasia

The vaginal microbial flora of 106 women with histopathologically confirmed cervical intraepithelial neoplasia and 79 women without disease, was evaluated for Gardnerella vaginalis, Trichomonas vaginalis, Candida albicans and other yeasts. Flora morphology was assessed by gram staining of secretions. Cervical cultures were examined for Herpes Simplex virus, Cytomegalovirus and Neisseria gonorrhoeae. Chlamydia trachomatis antigens in cervical secretions were detected by enzyme immunoassay. Human Papillomavirus was identified by koilocytosis in cytologic or histopathologic specimens. Human Papillomavirus infection (P less than 0.00001), vaginal infection with Mycoplasma hominis (P = 0.012) and abnormal vaginal flora (P = 0.006) were significantly associated with CIN, suggesting that CIN may be promoted by vaginal microorganisms in conjunction with human papillomavirus cervical infection.

Herpes simplex virus type 2 infection and cervical cancer: a prospective study of 12 years of follow-up in Finland

This study was initiated to investigate the role of past herpes simplex virus type 2 (HSV-2) infection, as determined by serum antibody analysis, in the etiology of cervical neoplasia. Two Finnish registers, the registry of the Social Insurance Institution's Mobile Clinic Survey and the Finnish Cancer Registry, were linked. About 40,000 blood samples were drawn in 1968-72 and stored by the Social Insurance Institution. According to the Cancer Registry, 32 cases of cervical carcinoma or carcinoma in situ for which serum samples were available were diagnosed in this cohort during a follow-up of 12 years (1968-81). The serum samples of these individuals and age matched controls (2:1) from the cohort were analyzed for HSV-2 antibodies. HSV-2 infection as determined by the best available HSV-2 type-specific antibody assay, glycoprotein gG2-ELISA, was not related to cervical neoplasia, i.e., the risk of cervical neoplasia among the HSV-2 positive women was not higher than that among the negative ones (smoking-adjusted relative risk = 0.5, 95 percent confidence interval = 0.2-1.6). The results do not support the hypothesis that HSV-2 is an etiologic agent for cervical neoplasia.

A study of possible causal relations between squamous cell carcinoma of the penis and carcinoma of the cervix uteri

The authors investigated 26 regular sexual female partners of 24 men with squamous cell carcinoma of the penis. Neoplasms were diagnosed in 6 (23.1%) of the total of 26 women. STDs were found in 6 (23.1%) women. In 2 the cytologic findings on the cervix were classified as PAP III (PAP IIIa-CIN I, PAP IIIb-CIN III). Squamous cell carcinoma of the uterine cervix was found in 2 women (1 case PAP IV-CIN III; 1 case PAP V-suggestive of invasive carcinoma). Endometrial adenoacanthoma, mammary adenocarcinoma, squamous cell carcinoma of the right hand and non-Hodgkin's malignant lymphoma (centroblastic) were found in 1 case each.

Characterization of an immortalized human cell line derived from neonatal foreskin diploid fibroblasts

A new human skin cell line, designated as CCFS-1/KMC, immortalized from human neonatal foreskin diploid fibroblast cells, has been subcultured successfully in vitro for more than 500 passages. This anchorage-dependent cell line possesses many common features of transformation such as morphological and cytoskeletal changes, hypotriploidy, infinite lifespan, increasing plating efficiency and saturation density, and decreasing serum requirement and population doubling time. Human papillomavirus (HPV) type 18 DNA was detected in the cell line before and after immortalization by the polymerase chain reaction (PCR) method. Tumorigenicity, however, was not demonstrated in vivo. The isoenzyme activity of the cell line shows activation of a placental form of alkaline phosphatase and a changing lactate dehydrogenase isoenzyme pattern that is different from transformation by carcinogens. Class I HLA and class II HLA antigens are constitutively expressed on this skin cell line. Here we report that these immortalized human fibroblasts derived from neonatal HPV-18-DNA-contained diploid fibroblasts possess double minute chromosomes (DMs), a karyotypic aberration usually found in cancer cells.

Ten year follow-up study of women presenting to a genitourinary medicine clinic with anogenital warts

One hundred heterosexual women presenting at our clinic in 1979 with anogenital warts, were reviewed 10 years later. Median duration of warts following initial clinic attendance was 2 months (range 0-120 months). In 1979 cervical PAP smear results were available for 76 patients; cervical intraepithelial neoplasia (CIN) was seen in 15/76 (19.7%) women; 3 (4%) women had low grade CIN, 12 (15.7%) women had high grade CIN. Nineteen women had had treatment for CIN between 1979 and 1989, 7 laser ablation, 9 cone biopsy, 2 laser ablation and cone biopsy, and one woman laser ablation, cauterization and cone biopsy. At 10-year follow-up in 1989 4/100 women had anogenital warts, 12/100 women had cytological evidence of CIN (7 low grade, 5 high grade), and 37/100 women had CIN detected on colposcopic biopsy (31 low grade, 6 high grade). No women developed invasive cervical carcinoma during the study period. CIN lesions, detected in 1979, regressed without any treatment in 2 women. Colposcopic biopsy was 3.1 times more sensitive than single cervical PAP smear at detecting CIN (4.4 times as sensitive in detecting low grade CIN; 1.2 times as sensitive in detecting high grade CIN). In 1989 CIN was detected in 7/19 (36.8%) of women who had undergone cervical treatment between 1979 and 1989, and in 35/81 (43.2%) of women having no cervical treatment within this period (chi squared P greater than 0.5). These findings suggest that cervical laser ablative therapy and cone biopsy do not in the long term influence the natural history of cervical human papilloma virus-associated disease (CIN) in women with anogenital warts.(ABSTRACT TRUNCATED AT 250 WORDS)

[Epidemiological aspects of cervical neoplasms]

A review concerning the epidemiological issues relating to cervical cancer, one of the most frequent in the women of developing countries, was undertaken in Brazil, the incidence rate varies from 23.7/100,000 in Porto Alegre to 83.2/100,000 in Recife. In the United States, the 1978 incidence rate was 6.8/100,000 in white women and 14.7/100,000 among black women. Several studies have suggested the hypotheses that cervical cancer could be related to some venereal agent. The evidences have shown the human papillomavirus (HPV) to be the main etiological agent. Several studies on the validity of such a hypotheses were realized and it became clear that there does in fact exist a relationship between the HPV and cervical cancer. Finally, the better known risk factors, such as sexual behaviour, smoking and the contraception were studied in the light of the various etiological hypotheses.

Epstein-Barr virus--a possible missing link in the initiation of cervical carcinogenesis?

Salient epidemiological and molecular biological features of Epstein-Barr virus (EBV) infection correlate well with the natural history of carcinoma of the cervix. It is therefore hypothesised that the incorporation of EBV into the genome of cervical epithelial cells at an early age (teens) could be an important early event in cervical carcinogenesis.

Risk factors of female cancers in Ragusa population (Sicily)--1. Endometrium and cervix uteri cancers

A case-control study on breast, cervix and endometrium cancer cases registered in Ragusa between January 1, 1983 and June 30, 1985 has been conducted. Information on risk factors has been obtained by means of a structured questionnaire. Risk factors for endometrium cancer were: few children (1-2 vs greater than 4 OR 15.18, 95%CL 1.96-117.64), oestrogenic treatment (OR 2.20, 95%CL 1.05-4.90), obesity (Quetelet index greater than 30 vs less than 22 OR 10.42, 95%CL 1.30-83.86), family history (OR 2.87, 95% CL 1.05-7.83). Risk factors for cervix uteri cancer were: multiple abortions (greater than 2 vs 0 OR 9.87, 95%CL 1.46-66.66), no contraception (OR 8.33, 95%CL 2.38-25.00), younger age of mother at birth (OR 6.89, 95%CL 1.71-27.70). Age at menarche, age at menopause and years of fertile life were not found to be related to either endometrium or cervix uteri cancer. The existence of influencing differences (ancestry, environment, lifestyle) has been postulated.

Specific chromosomal abnormalities characterize fibrosarcomas of bovine papillomavirus type 1 transgenic mice

In the BPV1.69 line of transgenic mice, the bovine papillomavirus type 1 genome elicits both benign dermal fibroblastic proliferation (fibromatoses) and malignant fibrosarcomas. Because these lesions arise only with time, nonviral factors appear to be involved. We have karyotyped several primary tumors as well as a series of low-passage cell lines derived both from fibromatoses and from fibrosarcomas. The fibrosarcomas, but not the preneoplastic fibromatoses, show consistent abnormalities of one or both of two chromosomes, chromosome 8 (trisomy or duplication) and chromosome 14 (monosomy or translocation). The chromosomal abnormalities are not a direct consequence of the viral integration, which we have mapped to chromosome 15 by in situ hybridization. These results suggest that transgenic mice can be used to study the role(s) of cytogenetic changes in tumorigenesis and may direct the search for genes involved in tumor progression.

Malignant transformation of anorectal giant condyloma acuminatum (Buschke-Loewenstein tumor)

Giant condyloma acuminatum, originally described by Buschke and Loewenstein in 1925 as a lesion of the penis, is more rarely seen in the anorectum and is characterized by clinical malignancy in the face of histologic benignity; however, malignant transformation to frankly invasive squamous-cell carcinoma has been described. Malignant transformation has been reported in 15 patients with "ordinary" condylomata acuminata as well. Twenty giant condylomata acuminata have been previously reported, six of which (30 percent) went on to develop squamous-cell carcinoma. The authors report eight cases of giant condylomata acuminata with invasive squamous-cell carcinoma developing in four patients. Light and electron microscopic methods were used to verify the diagnosis of squamous-cell carcinoma and/or giant condyloma acuminatum in our cases. Human papillomavirus (HPV), known to cause condylomata acuminata, is also known to induce these tumors. The authors support the hypothesis that giant condyloma acuminatum represents an intermediate lesion in a pathologic continuum from condyloma acuminatum to squamous-cell carcinoma. These lesions have a propensity for recurrence, likelihood of malignant transformation, and significant mortality. Therefore, early and radical local excision, and in cases of recurrence, invasion, or malignant transformation, abdominoperineal resection, along with vigilant follow-up, provides the only current hope for cure.

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.

Human papillomaviruses and carcinomas

The recognition of multiple types of human papillomaviruses has resulted in remarkable progress in the detection of persisting viral nucleic acid sequences in carcinomas. The consistent transcription in tumors of two early open reading frames, E6 and E7, with few exceptions (Lehn et al., 1985), indicates a role for the products of these genes in the induction and/or maintenance of the transformed state. A number of studies have shown that in vitro transformation can be achieved by transfection of E6/E7 DNA, and proteins encoded by these DNA sequences can be demonstrated in primary human keratinocytes immortalized by this DNA (Kaur et al., 1989). Mutagenesis experiments are needed to determine the absolute requirement for and function of these genes in transformation. A preferential association of some types with benign lesions while others may be frequently found in malignant tumors has been observed. HPV types 5 and 8 in epidermodysplasia verruciformis patients and types 16, 18, 31, 33, etc. in genital lesions are most frequently associated with progression to malignancy, whereas other types, such as HPV-6,-10, -11, and -20, are regularly identified in benign warts. Such distinctions are not absolute but provide the initial steps toward establishing a causal role for some human papillomaviruses in carcinomas. The need for well-designed epidemiological studies in concert with optimum molecular and serologic evaluations is evident (Armstrong et al., 1988). The data from human and animal studies indicate that papillomaviruses contribute significantly to the development of many, if not all, carcinomas, but we do not yet have a clear understanding of the importance of other interacting viral, chemical, or cellular factors. The application of gene cloning and non-stringent hybridization (Law et al., 1979) has provided us with an apparently ever-increasing catalog of human papillomaviruses. More effort is now required to establish their prevalence, the natural history of infection, and the mechanism of neoplastic transformation.

Validity of cigarette smoking habits in three epidemiologic studies in Utah

Utah has lower incidence and mortality for many smoking-related forms of cancer and heart disease. It is an important epidemiologic question to assess whether the population attributable risk associated with cigarette smoking in this low-risk population is biased from under-reporting because of societal pressures not to smoke. To answer this question, we compared reported cigarette use to serum cotinine values in three different epidemiologic study designs. Included in these analyses were data from men interviewed for a cross-sectional study of dietary intake and hormones, women interviewed as a part of a case-control study of cervical cancer, and men interviewed in conjunction with a cardiovascular disease and hypertension family follow-up study. Cross-sectional study participants reported accurate cigarette usage 93.8% of the time; case-control participants accurately reported cigarette use 98.5% of the time; participants interviewed in the family cohort study correctly reported usage 82.8% of the time. Most inaccurate reporting of smoking was by exsmokers being followed for a disease known to be linked to smoking. The low attributable risk of smoking related to diseases in Utah is not from underreporting of cigarette smoking, and makes Utah an ideal population to examine other risk factors for diseases where smoking increases risk.

Enhancement of bovine papillomavirus-induced cell transformation by tumour promoters

Cultured C3H/10T1/2 cells transfected with the plasmid pdBPV-1 were used as targets, and the frequency of transformed colonies as the endpoint to test the enhancing capacity of four promoters: 12-O-tetradecanoylphorbol-13-acetate (TPA), 4-O-methyl-tetradecanoylphorbol-13-acetate (4-O-methyl-TPA), mezerein and phorbol-12-retinoate-13-acetate (PRA). The frequency of the transfected C3H/10T1/2 cells to form transformed colonies was enhanced in the following order: mezerein greater than PRA greater than TPA greater than 4-O-methyl-TPA. The amount of promoters required to promote a tenfold increase in transformed cells was 0.24, 0.81, 30 and 100 ng/ml mezerein, PRA, TPA and 4-O-methyl-TPA, respectively. A significant promoting effect was obtained by a 3.5-day exposure to mezerein regardless of whether it was added at different time intervals after transfection with BPV-DNA. The examined promoters lacked genotoxic activity, as tested on Chinese hamster ovary cells, using chromatid aberrations and exchanges, frequency of macronuclei, unscheduled DNA synthesis (UDS) and inhibition of UDS as endpoints. The usefulness of BPV-1-induced transformation as a bioassay for detecting chemicals with promoting activities is discussed.

Papillomavirus and cervical cancer: a clinical and laboratory study

It is now widely accepted that HPV types 16, 18, 31, and 33 are associated with the development of high grade intraepithelial neoplasia and malignant lesions in the cervix. On this basis, the identification of HPV types in cervical scrape samples has been advocated as a supplement to cytological screening tests. However, little is known of the distribution of the virus at different sites in the lower female genital tract or of how this distribution may change during the natural course of HPV infection. In this survey, HPV DNA dot hybridizations and, in some instances, Southern blot hybridizations with mixed HPV 6/11 and 16/18 probes were undertaken to detect HPV DNA in cervical scrapes and biopsies of the cervix, vagina, and vulva. A total of 92 women attending a Sydney hospital were screened: 59 of these patients had cervical disease, either invasive cervical carcinoma (CaCx) or cervical intraepithelial neoplasia (CIN), grades I-III. A group of 33 women who lacked evidence of cervical abnormalities served as controls. HPV DNA, predominantly type 16/18, was detected in the cervical biopsies of 96% of the CaCx patients, 80% of the CIN III patients, and 65% of the CIN I-II patients. In contrast only 9% of the cervical biopsies from the control group contained detectable HPV 6, 11, 16, or 18 DNA. A high proportion of the women with cervical abnormalities had evidence of concurrent vaginal and/or vulval papillomavirus involvement. The significance of these findings for routine screening and subsequent management of patients with HPV-associated cervical disease is discussed.

Multiple primary tumours in women with vulvar neoplasms: a case-control study

We sought to determine whether women with in situ or invasive squamous cell vulvar cancer were more likely than other women to have had a previous or concurrent tumour at other anogenital sites. One hundred and fifty-eight women with vulvar cancer were identified who were first diagnosed during 1980-1985, were ages 18-79 years at that time, and were residents of one of three counties in western Washington. Two control groups were selected: (1) from records of hospital pathology departments, a sample of 113 women with certain benign conditions of the vulva; (2) through random digit dialing, a sample of 212 women from the general population of these counties. Information on a history of other cancers, and on sexual, reproductive, medical, and demographic characteristics was collected from cases and controls in at-home interviews. Cases were more likely to report a history of other anogenital cancers than were controls, with relative risks of 3.5-29.8, depending on the type of case group and type of control. These associations were not explained by case-control differences in demographic characteristics or frequency of cervical screening. On the other hand, prior or concurrent non-anogenital cancers were equally common in cases and controls. These results support the hypothesis that the different anogenital cancers have at least one aetiology in common.

The effectiveness of cervical screening: a population-based case-control study

The cervical smear histories of 36 women with invasive cervical cancer were compared to those of 120 age-matched controls, drawn from local registrar's offices. Of the cases 47% were screened at least once, while for the controls this figure was 68%. The relative risk of getting invasive cervical cancer for women screened at least once compared to women who were never screened was 0.32. The most important confounding factor was age at first intercourse. Contrary to other studies however, it was found that women who were younger when having first intercourse were screened more often. After correcting the relative risk of screened vs unscreened for age at first intercourse, the relative risk became 0.22. When the length of the interval since the last smear was considered, the relative risk was 0.18 when the smear was made between 2 and 5 years earlier and 0.30 when this smear was made more than 5 years earlier. These results support the assumption that screening is effective in the prevention of invasive cancer of the uterine cervix. Even a screening interval of more than 5 years provides considerable protection.

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.

The Pap smear revisited

Papanicolaou smear screening for cervical cancer has become an established practice in most developed countries. This is because the cervix is relatively accessible to investigation and treatment, and early stages in the morphogenesis of cervical cancer are both recognizable and easily treated. The Pap smear is a valid test. It is simple, relatively inexpensive, reliable, and free of risk. Although the test has far from perfect sensitivity, it has high specificity, and false-positive results are rare. In most reported series, the majority of false-negative results have been found to be attributable to collection errors rather than laboratory errors. Despite the importance of Pap smear screening, controlled prospective trials have not been undertaken to determine its efficiency in reducing cervical cancer incidence and mortality. However, countries with well-organized programmes, wide population coverage and correct follow-up appear to have had some impact on mortality from cervical cancer. Nevertheless, coverage of high-risk groups, particularly women over 40 years of age, remains the greatest problem. Recommendations on the frequency of testing vary considerably. Statistical models indicate triennial testing may deliver almost all of the effectiveness of annual testing at a substantially reduced cost, but the numerous reports of false-negative results argue strongly in favour of annual screening. It is possible that these problems may be solved in the future by increasing the sensitivity of the test and/or by the use of additional tests.

The influence of nicotine abuse and diabetes mellitus on the results of primary irradiation in the treatment of carcinoma of the cervix

References in the literature to the frequent occurrence of cervix carcinoma accompanied by nicotine abuse led us to investigate the effects of cigarette smoking on the results of treatment in primary irradiation of cervix carcinoma. As not only nicotine abuse but also diabetes mellitus can lead to angiopathy, we also investigated the influence of diabetes mellitus on the results of treatment. Of 410 nonsmokers with carcinoma of the cervix in Stages I and II, 260 (63.4%) reached the 5-year limit, but only 62 of 115 smokers survived (53.9%). In Stages III and IV there were significantly less favorable rates of cure in patients with nicotine abuse. Of 626 nonsmokers with cervix carcinoma in Stages III and IV, 212 survived (33.9%); but of 153 smokers, only 31 (20.1%) could be cured (P less than 0.01). The frequency of side effects of primary irradiation was distinctly higher in smokers than in nonsmokers. Reversible complications occurred in 17.5% of the smokers and 15.5% of the nonsmokers. Severe irreversible changes occurred in 28% of the smokers versus 15.2% of the comparative group of nonsmokers (P less than 0.01). The injuries caused by smoking not only reduce the biologic effectiveness of ionizing radiation but also increase the rate of side effects due to the deficient capacity for regeneration of the tissue surrounding the tumor. With diabetes as a complication, however, no significant changes in frequency of side effects were noted. Five-year survival in diabetic patients was affected in Stage I and II, but not in the advanced stages.

Prospective evaluation of risk of cervical cancer after cytological evidence of human papilloma virus infection

846 women with cytological evidence of human papillomavirus infection on their Papanicolaou smears in 1979 were followed for the subsequent development of cervical malignant disorders. Carcinoma-in-situ developed in 30 women during the next 6 years, compared with an expected number of 1.9 by general population incidence figures, giving a relative risk of 15.6. The risk was greatly increased (38.7) in women younger than 25 years when the cytological diagnosis of human papillomavirus infection was made.

Epidemiology of uterine cervical cancer

The epidemiology of cervical cancer presents a number of unique challenges, mainly with respect to disentangling correlated factors and to elucidating biological mechanisms. The available evidence suggests a complex multifactorial etiology, although the relative contributions of risk factors and their interactions remain obscure. Infectious agents are strongly suspected, but as yet not conclusively identified. It is also unclear whether there are subgroups of women or periods of life that are most susceptible to the action of infectious agents, and the contribution of the "male factor" needs to be defined. Several epidemiologic leads can be pursued through biochemical and molecular techniques. Most promising is the recent evidence linking certain HPV types to cervical abnormalities, including cancer, and newly developed probes can be incorporated into epidemiologic studies to evaluate an array of risk factors. Endocrine and metabolic assays may be helpful in clarifying the role of exogenous and possibly endogenous hormones. The effects of cigarette smoking may be further evaluated by studying constituents of tobacco smoke and their metabolites in cervical mucus. Finally, the relationship of diet to cervical cancer should be assessed by examining the levels of micronutrients, trace minerals, and other nutritional indices in body tissues and fluids, as well as through interview data. An understanding of cervical cancer etiology will require a better identification of risk factors for precursor lesions as well as factors that enhance their progression to invasive cancer. Through studies that focus on disease stage and time-related events, it should be possible to clarify the multi-stage processes involved in cervical carcinogenesis, and those factors that may inhibit as well as promote transition rates. The protective effects of screening programs deserve further attention, and research into dietary factors may lead in time to nutritional intervention. Investigation by cell type should also be pursued to define the epidemiology of the rarely occurring adenocarcinomas and adenosquamous carcinomas of the cervix. Finally, preventive strategies should be targeted to high-risk populations, especially those of the lower socioeconomic classes and with limited access to medical care. The need for a renewed focus on epidemiology and prevention is emphasized by recent increases in exposure to several postulated risk factors, including sexual promiscuity, oral contraceptives, and smoking.(ABSTRACT TRUNCATED AT 400 WORDS)