Parity as a risk factor for cervical cancer

Shared chemoresistance genes in ESCC and cervical Cancer: Insights from pharmacogenomics and Mendelian randomization

BACKGROUND

Neoadjuvant chemotherapy, particularly the use of platinum-based compounds and taxanes, is pivotal in the treatment of epithelial-derived tumors, such as cervical cancer and esophageal squamous cell carcinoma (ESCC); however, resistance remains a significant challenge. Utilizing Mendelian randomization (MR) with pharmacogenomics offers a novel approach to understanding the genetic underpinnings of drug responses, thereby aiding in personalized treatment.

METHODS

Single-cell RNA sequencing (scRNA-seq) analysis revealed a shared cellular subpopulation of CD8 + T effector memory (CD8 + TEM) cells that are pivotal in mediating chemotherapy resistance in ESCC and cervical cancer. A two-sample approach was employed for MR using data from genome-wide association studies, focusing on single nucleotide polymorphisms (SNPs) linked to CD8 + TEM cell expression. The SNPs were carefully selected, and statistical models, including the Wald ratio and inverse variance weighted methods, were used for robust causal effect estimation. These were supplemented by MR-Egger and weighted median analyses to address pleiotropy and variant heterogeneity. 3-(4,5-Dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) and immunohistochemistry assays were used to verify the relationship between the gene and drug sensitivity.

RESULTS

Increased proportion of CD8 + TEM cells were observed in resistant samples. MR identified IL32, SPOCK1, and TRBC2 as key genes associated with resistance to cisplatin, carboplatin, and paclitaxel, respectively. These findings were validated across various cohorts and underscored the role of CD8 + TEM cells in drug responsiveness. The results of the MTT and immunohistochemistry assays confirmed the MR findings.

CONCLUSIONS

Our study highlights the significant role of CD8 + TEM cells in the chemoresistance of ESCC and cervical cancer and identified three genetic markers crucial for resistance to common chemotherapeutic agents. These findings suggest potential pathways for developing personalized treatment strategies, offering clinically relevant insights that could enhance therapeutic efficacy and help overcome drug resistance in patients with ESCC or cervical cancer.

Patterns of Care, Prognostic Factors, and Survival Outcomes for Patients of Cervical Carcinoma: A Study From North India

OBJECTIVES

Cervical cancer is the second most common malignancy among Indian women after breast cancer. This study was undertaken to determine the pattern of care, long-term survival outcomes, and prognostic factors for cervical cancer patients treated at a tertiary care cancer centre in North India.

METHODS

Ten-year data was retrieved for 435 stage I-IVA carcinoma cervix patients treated between 2009 and 2019. A sociodemographic profile of the patients, treatment methods, and conditions at follow-up were obtained.

STATISTICAL ANALYSIS

 Data was analyzed using Stata 15.1 (StataCorp LLC, College Station, Texas, United States). Qualitative variables were shown as frequencies/percentages, and quantitative as means/standard deviations. Key endpoints were overall, disease-free, and locoregional survival. Kaplan-Meier curves represented survival. Cox regression models assessed parameter influence. Statistical significance was set at p < 0.05, with hazard ratios and 95% confidence intervals reported.

RESULTS

Fourteen (3.2%) patients underwent surgery; of the patients who underwent surgery, except two patients who underwent surgery alone, all patients received external beam radiotherapy (EBRT) followed by EBRT (26.4%) or brachytherapy boost (72.4%). Seventy-one per cent of patients received more than four cycles of concurrent chemotherapy. The median overall survival (OS) was 42.04 (0.25-171) months, and the median disease-free survival (DFS) was 32.85 months (1-171) months. The median overall survival was 58.76%, and the two-year and five-year overall survival percentages were 81.34% and 64.52%, respectively. The median time to locoregional relapse and distant metastasis was 35 (1-171) and 37.6 (1-171) months, respectively. Bilateral parametrial involvement was a predictor of poor OS (p = 0.039), DFS (p = 0.039), and locoregional failure-free survival (LFFS) (p = 0.020). Age less than 50 years was a predictor of worse DFS (p = 0.034) and LFFS (p = 0.005), while paraaortic nodal involvement was a predictor of worse DFS (p = 0.045). Grade III tumours neared numerical significance (p = 0.051) for worse distant metastases-free survival.

CONCLUSION

Bilateral parametrial involvement was the most significant factor for OS, DFS, and LFFS. Paraaortic nodal involvement predicted poor DFS and young age was associated with poor DFS and LFFS.

The Preventive Role of the Vitamin D Endocrine System in Cervical Cancer

Vitamin D along with its active metabolite calcitriol and its metabolic and signaling system, known as the vitamin D endocrine system, have been widely recognized as a pivotal regulator of calcium homeostasis in addition to non-calcemic antitumoral effects in a variety of human cancers, including cervical cancer. Several studies have found an inverse relationship between the incidence of cervical neoplasia and vitamin D levels. This narrative review updates the current evidence supporting the notion that the vitamin D endocrine system has a preventive role on cervical cancer, mainly in the early phases of the disease, acting at the level of suppressing cell proliferation, promoting apoptosis, modulating inflammatory responses, and probably favoring the clearance of human papillomavirus-dependent cervical lesions. Although an optimal vitamin D status helps in the prevention and regression of low-grade squamous intraepithelial lesions of the cervix, it appears that vitamin D alone or combined with chemotherapeutic agents has little effectivity once advanced cervical cancer is established. These observations suggest that an optimal vitamin D status might exert beneficial actions in the early phases of cervical cancer by preventing its onset and progression.

Cervical cancer in Cape Verde: reappraisal upon referral to a tertiary cancer centre

Background

Cervical cancer (CC) is the first cause of cancer-related deaths among Cape Verdean women. The absence of a national screening programme and a lack of dedicated cancer treatment facilities contribute to its high mortality rate. In an effort to improve the prognosis of these women, a health cooperation agreement was established between Portugal and Cape Verde (CV), allowing their evacuation to Portuguese hospitals. Our aim was to characterise CC among CV women, and to assess the response given to these patients in Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG), so that their treatment and follow-up protocols can be optimised and overall prognosis improved.

Methods

Retrospective evaluation of women diagnosed with CC in CV that underwent therapy in IPOLFG between 2013 and 2020. Risk factors, demographic and tumour characteristics, treatment and outcomes were reviewed.

Results

Fifty-eight patients were included. Squamous cell carcinoma was the most frequent (91.5%) histological type. HPV DNA was present in 25 out of 26 samples.The agreement rate between the pathology analysis performed in CV and in Portugal was high (87.9%); however, the agreement regarding the FIGO stage was low (15.5%). This may be explained by both the time interval between diagnosis and treatment (around 6 months) and by the absence of resources to accurately stage the disease in CV. In IPOLFG, 77.6% of patients received combined chemo-radiotherapy. Post-treatment follow-up varied widely, due to disease-related and bureaucratic issues. Eighteen patients developed cancer-related complications and/or cancer-related death. The survival rate and median overall survival (OS) in our cohort were of 89.7% and 73.2 months, respectively.

Conclusions

Although most women had advanced-stage disease, the OS in our cohort was better than what has been reported for other African countries, probably because state-of-the-art treatment, frequently not accessible in those countries, was offered to all patients.

High parity is associated with increased risk of cervical cancer: Systematic review and meta-analysis of case-control studies

Background:

Cervical cancer is the fourth most common cancer among women. High parity has long been suspected with an increased risk of cervical cancer. Evidence from the existing epidemiological studies regarding the association between parity and cervical cancer is variable and inconsistent. Therefore, the objective of this systematic review and meta-analysis was to synthesize the best available evidence on the epidemiological association between parity and cervical cancer.

Methods:

Case–control studies reporting the association between parity and cervical cancer were systematically searched in databases like MEDLINE/PubMed, HINARI, Google scholar, Science direct, and Cochrane Libraries. All studies fulfilling the inclusion criteria and published between 2000 and 7 March 2020 were included in this meta-analysis. This study reported according to PRISMA guideline. Cochran’s Q-statistics and I² tests were performed to assess heterogeneity among included studies. Egger’s regression analysis was performed to assess publication bias. A random-effect meta-analysis model was used to compute pooled odds ratio of the association between parity and cervical cancer.

Results:

A total of 6685 participants (3227 patients and 3458 controls) were incorporated in the 12 studies included in this meta-analysis. The meta-analysis revealed that women with high parity had 2.65 times higher odds of developing cervical cancer compared to their counterparts (odds ratio = 2.65, 95% confidence interval = 2.08–3.38).

Conclusion:

High parity is positively associated with cervical cancer. Strong epidemiological studies are recommended to further explore the mechanisms and role of parity in the causation of cervical cancer.

Ranking lifestyle risk factors for cervical cancer among Black women: A case-control study from Johannesburg, South Africa

BACKGROUND

Aside from human papillomavirus (HPV), the role of other risk factors in cervical cancer such as age, education, parity, sexual partners, smoking and human immunodeficiency virus (HIV) have been described but never ranked in order of priority. We evaluated the contribution of several known lifestyle co-risk factors for cervical cancer among black South African women.

METHODS

We used participant data from the Johannesburg Cancer Study, a case-control study of women recruited mainly at Charlotte Maxeke Johannesburg Academic Hospital between 1995 and 2016. A total of 3,450 women in the study had invasive cervical cancers, 95% of which were squamous cell carcinoma. Controls were 5,709 women with cancers unrelated to exposures of interest. Unconditional logistic regression models were used to calculate adjusted odds ratios (ORadj) and 95% confidence intervals (CI). We ranked these risk factors by their population attributable fractions (PAF), which take the local prevalence of exposure among the cases and risk into account.

RESULTS

Cervical cancer in decreasing order of priority was associated with (1) being HIV positive (ORadj = 2.83, 95% CI = 2.53-3.14, PAF = 17.6%), (2) lower educational attainment (ORadj = 1.60, 95% CI = 1.44-1.77, PAF = 16.2%), (3) higher parity (3+ children vs 2-1 children (ORadj = 1.25, 95% CI = 1.07-1.46, PAF = 12.6%), (4) hormonal contraceptive use (ORadj = 1.48, 95% CI = 1.24-1.77, PAF = 8.9%), (5) heavy alcohol consumption (ORadj = 1.44, 95% CI = 1.15-1.81, PAF = 5.6%), (6) current smoking (ORadj = 1.64, 95% CI = 1.41-1.91, PAF = 5.1%), and (7) rural residence (ORadj = 1.60, 95% CI = 1.44-1.77, PAF = 4.4%).

CONCLUNSION

This rank order of risks could be used to target educational messaging and appropriate interventions for cervical cancer prevention in South African women.

Higher Parity Is Associated With Lower Mortality in a European Population of Women With High Fertility: Results From Ireland

Research has often found a U- or J-shaped association between parity and mortality. Many researchers have suggested repeated pregnancy, childbirth, and lactation taxes the body beyond a certain parity level. Available research has concentrated on populations with controlled fertility or historic populations. Ireland presents an opportunity to explore these associations in a modern sample with high fertility. We use data from the Irish Longitudinal Study on Ageing (TILDA) to test whether parity is associated with mortality in women aged 50 years or over (n = 4177). We use Cox proportional hazards models to model survival and adjust for demographics and early life circumstances. We test whether a number of health characteristics mediate these effects. Models were also stratified by birth cohort to test possible cohort effects. Higher parity was associated with lower risk of mortality, even after adjustment for early life and socioeconomic circumstances. This effect was not mediated by current health characteristics. The effects were largely driven by those born between 1931 and 1950. Increasing parity is associated with decreasing mortality risk in this sample. The effects of parity could not be explained through any of the observed health characteristics. These findings are in contrast to much of the literature on this question in similar populations. Lack of fertility control in Ireland may have "selected" healthier women into high parity. Social explanations for these associations should be further explored.

Gardnerella vaginalis and Trichomonas vaginalis infections and the risk of persistence or progression of low-grade cervical intraepithelial neoplasia

Gardnerella vaginalis (GV) and Trichomonas vaginalis (TV) infections have been proposed as risk factors for persistence or progression of low-grade precancerous cervical lesions (CIN1/L-SIL). However, their role is still undefined. We aimed to assess if GV and TV infections affect the risk of persistence/progression of CIN1/L-SIL. A retrospective cohort study was performed to assess the risk of CIN1/L-SIL persistence or progression, persistence alone and progression alone in patients with GV and/or TV infections (GV + and/or TV+), only GV (GV+), only TV (TV+), or GV and TV coinfections compared to patients without these infections. Relative risk (RR) with 95 % confidence intervals (CI) was adopted (significant p-value>0.05). Two hundred and seventy patients were included. RR for CIN1/L-SIL persistence or progression was 1.63 in GV + and/or TV+ (p = 0.02), 1.99 in GV+ (p = 0.0008), 0.25 in TV+ (p = 0.32), 1.78 in coinfection (p = 0.26). RR for persistence was 1.55 in GV + and/or TV+ (p = 0.1), 2.179 in GV+ (p = 0.0013), 0.32 in TV+ (p = 0.41), 0.45 in coinfection (p = 0.55). RR for progression was 1.92 in GV + and/or TV+ (p = 0.22), 1.34 in GV+ (p = 0.68), 1.16 in TV+ (p = 0.91), 8.39 in coinfection (p = 0.0002). In conclusion, GV infection may be a risk factor for CIN1/L-SIL persistence. TV infection alone does not significantly affect the risk of persistence or progression of such lesions, while it may greatly increase the risk of progression when associated with GV infection.

Fas Ligand (FasL) in Association with Tumor-Infiltrating Lymphocytes (TILs) in Early Stage Cervical Cancer

OBJECTIVE

To date, little is known about the roles of FasL and TILs in cervical cancer. This study aims to determine the correlation between FasL expression and TILs presence in cervical cancer.

METHODS

In this study, we analysed the FasL and TIL presence in 32 squamous cell carcinoma or adenocarcinoma that were obtained from early stage (≤ IIA2) cervical cancer patients using immunohistochemistry. The level of FasL and TIL was assessed qualitatively, and then quantified with the H-Score system.

RESULTS

Most of the patients were between 30 to 50 years old (59,4%), and had never taken pap smear examination before (96,9%). Based on the Pearson analysis of FasL and TIL presence, we found that FasL was inversely correlated with CD45 or TIL number when the level of FasL is above 140 and the CD45 is below 160. Based on Chi-Square test of FasL and TIL classification, there was a nine-fold odds ratio (OR) of lower TILs classification in high expression of FasL classification (OR 9, p=0.01).

CONCLUSION

An inverse correlation between FasL expression and TILs level, that might indicate FasL-induced TILs apoptosis in tumor tissue, was observed. The strong inverse correlation between FasL and TILs presence showed some insight about the interactions between cancer cells and its surroundings inside of the cervical cancer tissue. This might also be further developed to tailor a prognostic marker that can predict the outcome of therapy in patients, not only in cervical cancer, but generally in all cancer.

Population risk factors for late-stage presentation of cervical cancer in sub-Saharan Africa

BACKGROUND

Cervical cancer is the most prevalent malignancy in sub-Saharan Africa (SSA) with many women only seeking professional help when they are experiencing symptoms, implying late-stage malignancy and higher mortality rates. This ecological study assesses population-level exposures of SSA women to the numerous risk factors for HPV infection and cervical cancer, against late-stage presentation of cervical cancer.

MATERIALS AND METHOD

A literature review revealed the relevant risk factors in SSA. Open-access databases were mined for variables closely representing each risk factor. A proxy for late-stage presentation was used (ratio of incidence-to-mortality, IMR), and gathered from IARC's GLOBOCAN 2012 database. Variables showing significant correlation to the IMR were used in stepwise multiple regression to quantify their effect on the IMR.

RESULTS

Countries with high cervical cancer mortality rates relative to their incidence have an IMR nearer one, suggesting a larger proportion of late-stage presentation. Western Africa had the lowest median IMR (1.463), followed by Eastern Africa (IMR = 1.595) and Central Africa (IMR = 1.675), whereas Southern Africa had the highest median IMR (1.761). Variables selected for the final model explain 65.2% of changes seen in the IMR. Significant predictors of IMR were GDP (coefficient = 2.189 × 10^-6, p = 0.064), HIV infection (-1.936 × 10^-3, p = 0.095), not using a condom (-1.347 × 10^-3, p = 0.013), high parity (-1.744 × 10^-2, p = 0.008), and no formal education (-1.311 × 10^-3, p < 0.001).

CONCLUSION

Using an IMR enables identification of factors predicting late-stage cervical cancer in SSA including: GDP, HIV infection, not using a condom, high parity and no formal education.

TP53 Codon 72 Polymorphism does not Affect Risk of Cervical Cancer in Patients from the Gambia

Aims

A case-control study was performed to investigate the relationship between cervical cancer and TP53 polymorphism at codon 72 in young black African women from The Gambia.

Materials and Methods

The TP53 polymorphism at codon 72 was examined by PCR amplification and SSCP analysis in 40 patients with primary cervical cancer and in 20 healthy women of the same age and from the same geographical area. The occurrence of TP53 polymorphism in combination with the HPV-16 E6 genotype (assayed by PCR) was evaluated.

Results

The distribution of TP53 genotypes in cervical cancer patients and in the control group was not statistically different (p=0.45) and homozygosity for argine at residue 72 was not associated with cervical cancer (odds ratio: 1.24; 95% confidence interval 0.21-9.16). Similarly, a different genotype distribution, cervical cancer and presence of HPV-16 E6 were not observed.

Conclusions

These results cannot rule out an association between TP53 polymorphism at codon 72, HPV infection and the etiology of cervical cancer in this population sample.

Risk Factors Associated with Invasive Cervical Carcinoma among Women Attending Jimma University Specialized Hospital, Southwest Ethiopia: A Case Control Study

Background

Cervical cancer is a more serious public health problem than other cancers in women in Sub-Saharan Africa in general and in Ethiopia in particular. Thus, this study assessed risk factors related to invasive cervical carcinomas in southwestern Ethiopia.

Methods

Unmatched case control study was conducted in Jimma University Specialized Hospital from April 1 to September 30, 2010. The study consisted of 60 cases (women who had cervical cancers based on histopathologic examination) and 120 controls (women with no cervical cancers). Semi-structured questionnaire was utilized for data collection. Vaginal examinations often visualized with speculum insertions were done for both cases and controls. Punch cervical biopsies were then performed for the suspected cases at Jimma University Hospital that serves about 15 million people in a catchment radius of 250 kms. Data were analyzed using SPSS version 13.0 software. Univariate and multivariate analyes were done to describe and identify independent predictors of cervical cancer.

Results

The mean ages of cases and controls were 47.7 (SD=10.8) and 35.5 (SD =10.5) years respectively. Older women (40–59 years), (OR= 4.7; 95%CI= 2.3–9.6), more than one husband (OR= 2.0; 95%CI=1.0–3.9), as well as more than one wife in lifetime, (OR= 3.0; 95% CI= 1.5–5.9), women who had more than 4 children, (OR =10.3, 95% CI= 3.6–29.0), and age greater than 25 years at first full term delivery, (OR= 8.8; 95% CI= 3.5–22.0) were statistically significant and the latter two were independently associated with invasive cervical cancer. Only 7(11.7 %) of cases and 58(48.3%) of controls ever heard of cervical cancers; however, 2(3.3%) of cases and 7(5.8%) of controls had ever had history of papaneocolous (pap) smear tests done.

Conclusion

Poor knowledge on cervical cancer was observed that required more work to be done to increase knowledge of mothers on cervical cancer and on associated risk factors. Behavioral communication activities and establishment of cervical cancer screening programs for the young could help reduce the advancement of cervical cancer particularly among the less knowledgeable, older and grand multiparous women in our parts of the world.

Awareness of cervical cancer risk factors and symptoms: cross-sectional community survey in post-conflict northern Uganda

BACKGROUND

Lack of awareness of risk factors and symptoms for cancer may lead to late diagnosis and poor prognosis.

OBJECTIVE

We assessed community awareness about cervical cancer risk factors and symptoms and perceptions about prevention and cure of cervical cancer in order to contribute data to inform interventions to improve cervical cancer survival.

DESIGN

Cross-sectional population-based survey.

SETTING AND PARTICIPANTS

We conducted this study in Gulu, a post-conflict district in Uganda in 2012. The sample included 448 persons aged 18 years and above, selected through a multi-stage stratified cluster sampling process.

DATA COLLECTION METHODS AND ANALYSIS

We collected data using a pretested structured questionnaire. Logistic regressions were used to determine magnitudes of associations between socio-demographic and outcome variables.

RESULTS

Most participants (444/448) had heard about cervical cancer. Known risk factors including multiple sexual partners, human papillomavirus infection, and early onset of sexual activity, were recognized by 88%, 82%, and 78% of respondents respectively. 63% of participants believed that prolonged use of family planning pills and injections caused cervical cancer. The majority of participants recognized symptoms of cervical cancer including inter-menstrual bleeding (85%), post-menopausal bleeding (84%), and offensive vaginal discharge (83%). 70% of participants believed that cervical cancer is preventable and 92% believed that it could be cured if diagnosed at an early stage.

DISCUSSION AND CONCLUSIONS

Recognition of cervical cancer risk factors and symptoms was high among study participants. Targeted interventions including increasing availability of HPV vaccination, population-based cervical screening and diagnostic services can translate high awareness into actual benefits.

Perception of human papillomavirus infection, cervical cancer and HPV vaccination in North Indian population

BACKGROUND

Human Papillomavirus (HPV) -associated cervical cancer is the second-most common cancer in women worldwide but it is the most frequent gynaecological cancer and cancer associated death in India women. The objective of this study was to assess knowledge about cervical cancer, HPV, HPV vaccine, HPV vaccine acceptance among school and undergraduates students and their parent's perception about acceptance of HPV vaccine in Northern part of India (Delhi and NCR regions).

MATERIALS AND METHODS

A qualitative questionnaire based survey among 2500 urban/rural students aged 12-22 years was conducted.

RESULTS

Overall, a low frequency (15%) of HPV and cervical cancer awareness was observed in students and their parents. However, the awareness was much higher in females belonging to urban setup compared to boys with a perception that HPV causes cervical cancer in women only. Additionally, only (13%) participants who were aware of cervical cancer and HPV) were willing to accept HPV vaccination. Apparently, parents of female students were two times more willing to accept HPV vaccination for their ward than male students (p<0.001; OR 95%CI = 2.09 (1.58-2.76).

CONCLUSION

Cervical cancer and HPV awareness among school, undergraduate students and also to their parents was found to be very low in this part of India. The level of awareness and education appears to be insignificant determinants in rural compared to urban setup. Better health education will be needed to maximize public awareness for cervical cancer prevention.

Assessment of cervical cancer risk in women between 15 and 49 years of age: case of Izmir

BACKGROUND

The aim of the study was to determine risk factors for cervical cancer for women in Izmir.

METHODS

This cross-sectional, descriptive field covered a population of 4319 women of reproductive age (15-49) (household registration in the Mukhtar's office-2007). A total of 1,637 women were included in the sample given a four-part questionnaire through face-to-face interview by visiting the women in their homes in order to determine socio-demographic factors, obstetric history, genital hygiene and the use of family planning methods. In addition, during the data collection process, the women were given group training in order to raise awareness of cervical cancer. The number and percentage distributions of the data were calculated.

RESULTS

While the average age of the women was 31.9±9.77 (Min: 15.00-Max: 49.00), education level of 43.4% of them was elementary school only. It was determined that 70.3% of the women experienced at least one pregnancy, 71.0% had vaginal delivery and 75.9% used a contraceptive method. In the study it was determined that among the cervical cancer related risks vaginal delivery, vaginal lavage and having three or more pregnancies had the highest rates, while having sexual intercourse before 16 years of age and having more than one sexual partner constituted lower rates. The rate of the women who stated not having a smear in the last three years was 82.4%.

CONCLUSIONS

Considering the case in terms of having Pap smear test, women's awareness on the risk factors and early diagnosis of cervical cancer was found to be low. Due to this reason, awareness of women has to be raised through education.

Differences in patterns of high-risk human papillomavirus infection between urban and rural low-resource settings: cross-sectional findings from Mali

BACKGROUND

The burden of cervical cancer is disproportionately high in low-resource settings. With limited implementation of human papillomavirus (HPV) vaccines on the horizon in the developing world, reliable data on the epidemiology of high-risk HPV (HR-HPV) infection in distinct geographic populations is essential to planners of vaccination programs. The purpose of this study was to determine whether urban patterns of HR-HPV occurrence can be generalized to rural areas of the same developing country, using data from Mali, West Africa, as an example.

METHODS

Urban and rural women in Mali participated in a structured interview and clinician exam, with collection of cervical samples for HPV DNA testing, to determine HR-HPV prevalence and correlates of infection. Correlates were assessed using bivariate analysis and logistic regression.

RESULTS

A total of 414 women (n=202 urban women; n=212 rural women) were recruited across both settings. The prevalence of HR-HPV infection in rural women was nearly twice that observed in urban women (23% v. 12%). Earlier age of sexual debut and fewer pregnancies were associated with HR-HPV infection among urban women, but not rural women. Twenty-six percent of urban women who had sexual intercourse by age 14 had an HR-HPV infection, compared to only 9% of those who had later sexual debut (p<0.01). Overall, age, income, and polygamy did not appear to have a relationship with HR-HPV infection.

CONCLUSIONS

Compared to urban women, rural women were significantly more likely to be infected with high-risk HPV. The patterns and risk factors of HR-HPV infection may be different between geographic areas, even within the same developing country. The high prevalence in both groups suggests that nearly all rural women and most urban women in Mali will be infected with HR-HPV during their lifetime, so the effects of risk factors may not be statistically apparent. To control HPV and cervical cancer in West Africa and the rest of the developing world, planners should prioritize vaccination in high-burden areas.

The Effects of Twins, Parity and Age at First Birth on Cancer Risk in Swedish Women

The effect of reproductive history on the risk of cervical, colorectal and thyroid cancers and melanoma has been explored but the results to date are inconsistent. We aimed to examine in a record- linkage cohort study the risk of developing these cancers, as well as breast, ovarian and endometrial cancers, among mothers who had given birth to twins compared with those who had only singleton pregnancies. Women who delivered a baby in Sweden between 1961 and 1996 and who were 15 years or younger in 1961 were selected from the Swedish civil birth register and linked with the Swedish cancer registry. We used Poisson regression to assess associations between reproductive factors and cancer. Twinning was associated with reduced risks of breast, colorectal, ovarian and uterine cancers, although no relative risks were statistically significant. The delivery of twins did not increase the risk of any cancers studied. Increasing numbers of maternities were associated with significantly reduced risks of all tumors except thyroid cancer. We found positive associations between a later age at first birth and breast cancer and melanoma, while there were inverse associations with cervix, ovarian, uterine and colorectal cancers. These findings lend weight to the hypothesis that hormonal factors influence the etiology of colorectal cancer in women, but argue against any strong effect of hormones on the development of melanoma or tumors of the thyroid.

Cervical cancer risk factors and feasibility of visual inspection with acetic acid screening in Sudan

Objectives:

To assess the risk factors of cervical cancer and the feasibility and acceptability of a visual inspection with acetic acid (VIA) screening method in a primary health center in Khartoum, Sudan.

Methods:

A cross-sectional prospective pilot study of 100 asymptomatic women living in Khartoum State in Sudan was carried out from December 2008 to January 2009. The study was performed at the screening center in Khartoum. Six nurses and two physicians were trained by a gynecologic oncologist. The patients underwent a complete gynecological examination and filled in a questionnaire on risk factors and feasibility and acceptability. They were screened for cervical cancer by application of 3%–5% VIA. Women with a positive test were referred for colposcopy and treatment.

Results:

Sixteen percent of screened women were tested positive. Statistically significant associations were observed between being positive with VIA test and the following variables: uterine cervix laceration (odds ratio [OR] 18.6; 95% confidence interval [CI]: 4.64–74.8), assisted vaginal delivery (OR 13.2; 95% CI: 2.95–54.9), parity (OR 5.78; 95% CI: 1.41–23.7), female genital mutilation (OR 4.78; 95% CI: 1.13–20.1), and episiotomy (OR 5.25; 95% CI: 1.15–23.8). All these associations remained statistically significant after adjusting for age, educational level, employment, and potential confounding factors such as smoking, number of sexual partners, and use of contraceptive method. Furthermore, the VIA screening method was found to be feasible and acceptable to participants.

Conclusion:

This pilot study showed that women who have uterine cervix laceration, assisted vaginal delivery, female genital mutilation, or episiotomy are at an increased risk of cervical cancer. It also showed that VIA is a feasible and acceptable cervical cancer screening method in a primary health care setting.

Assessing the relationship between HIV infection and cervical cancer in Côte d'Ivoire: a case-control study

Background

The association between HIV infection and invasive cervical cancer that has been reported may reflect differential prevalence of human papillomavirus (HPV) infection or uncontrolled confounding. We conducted a case-control study in a West African population to assess the relationship between HIV infection and invasive cervical cancer, taking into account HPV infection and other potential risk factors for cervical cancer.

Methods

Women with invasive cervical cancer (cases) or normal cervical cytology (controls) were recruited in a hospital-based case-control study in Abidjan, Côte d'Ivoire. Odds ratios and 95% confidence intervals (CI) were estimated in logistic regression analyses controlling for important cofactors.

Results

HIV infection was noted in 22/132 (16.7%) cases and 10/120 (8.3%) controls (p = 0.048). High-risk HPV infection was detected in cervical tumor samples from 89.4% of case-participants and in cervical cytology samples in 31.1% of control-participants. In logistic regression analysis, HIV infection was associated with cervical cancer in women with HPV (OR 3.4; 95% CI 1.1-10.8). Among women aged ≤ 40 years, risk factors for cervical cancer were high-risk HPV infection (OR 49.3; 95% CI 8.2-295.7); parity > 2 (OR 7.0; 95% CI 1.9-25.7) and HIV infection (OR 4.5; 95% CI 1.5-13.6). Among women aged > 40 years, high-risk HPV infection (OR 23.5; 95% CI 9.1-60.6) and parity > 2 (OR 5.5; 95% CI 2.3-13.4), but association with HIV infection was not statistically significant.

Conclusions

These data support the hypothesis that HIV infection is a cofactor for cervical cancer in women with HPV infection, and, as in all populations, the need for promoting cervical screening in populations with high prevalence of HIV infection.

Cervical cancer: the sub-Saharan African perspective

Cervical cancer is the second most common cancer in women worldwide and the leading cause of cancer deaths in developing countries. While incidence and mortality rates of cervical cancer have fallen significantly in developed countries, 83% of all new cases that occur annually and 85% of all deaths from the disease occur in developing countries. Cervical cancer is the most common cancer among women in sub-Saharan Africa. The incidence is on the increase in some countries. Knowledge and awareness of this disease on the continent are very poor and mortality still very high. Facilities for the prevention and treatment of cervical cancer are still very inadequate in many countries in the region. Governments in sub-Saharan Africa must recognise cervical cancer as a major public health concern and allocate appropriate resources for its prevention and treatment, and for research. Indeed, cervical cancer in this region must be accorded the same priority as HIV, malaria, tuberculosis and childhood immunisations.

Cervical cancer risk factors and predictors of cervical dysplasia among women in south-west Nigeria

AIM

This study identified predictors of cervical dysplasia and assessed the prevalence of risk factors for cervical cancer among women of different socioeconomic classes in Ogun State, Nigeria.

METHOD

In a two-phase study, self-reported information on cervical cancer awareness, risk factors and cervical cancer screening practices was obtained from 278 randomly selected working women. A random subset was screened for dysplasia using visual inspection with acetic acid (VIA).

RESULTS

Of the 278 women, 126 (45.3%) were semi-skilled while 152 (54.7%) were skilled and professional workers. Median age at first sexual intercourse was 19 years (range 13-29) and lower than the median age at first marriage (25 years). Gonorrhoea and genital warts were the commonest reported sexually transmitted infections. Only 12.2% of the women used male condoms as their primary method of birth control and 4.7% of the women had ever had a Papanicolaou smear, a practice that was significantly higher among the professional/skilled compared with semi-skilled workers (P = 0.031). Of the 125 screened, 20 (16%) had positive VIA. Young age at first sex (< or = 17 years) (OR = 3.7 (95% CI, 1.07-12.8)) and early first marriage (< 25 years) (3.3 (1.00-10.9)) were associated with a positive VIA. Women with lower parity (0-3) had borderline significantly increased risk of having a positive VIA (3.1 (0.9-10.6)). Women currently over 34 years and those without a history of sexually transmitted infections had lower risk of positive VIA (P > 0.05).

CONCLUSIONS

Acceptable screening services and cervical cancer awareness campaigns that address modifiable risk factors are urgently needed in this community.

Descriptive evidence that risk profiles for cervical intraepithelial neoplasia 1, 2, and 3 are unique

OBJECTIVE

This study aimed to estimate if risk factor profiles for histologically confirmed cervical intraepithelial neoplasia (CIN) 2 lesions differ from those for CIN 1 or 3.

METHODS

A total of 2,055 women positive for high-risk human papillomavirus, with a minimum of five cervical biopsies, were enrolled in the Shanxi Province Cervical Cancer Screening Study II. We evaluated risk factor profiles for CIN 2 in comparison with CIN 1 and 3. Polytomous logistic regression was used to generate odds ratios and corresponding 95% confidence intervals and to test for differences in odds ratios across histologic grades.

RESULTS

The risk for CIN 3 associated with three or more pregnancies and sexual intercourse within 4 months of childbirth was higher than that for CIN 2 (P(difference) = 0.02 and 0.0007, respectively). Significant differences in the associations of age groups with CIN 1 and 2 were observed, such that there were positive associations with CIN 2 but none for CIN 1. There was no difference in the association of number of sexual partners or reported number of abortions between CIN 1 and 2 or between CIN 3 and 2.

CONCLUSIONS

In our study, the patterns of risk factor profiles for CIN 1, 2, and 3 were unique. Conventional grouping of CIN 2 with 3 for analysis of risk factors may need revisiting.

Association between invasive cancer of the cervix and HIV-1 infection in Tanzania: the need for dual screening

Background

Cancer of the cervix is the second commonest malignancy in females worldwide and is the leading malignancy among women in Tanzania. Cancer of the cervix has been strongly associated with Human Papilloma Virus (HPV) which is a sexually transmitted disease. However, the role of HIV-1 in the aetiology of cancer of the cervix is less clear. Studies suggest that HPV and HIV-1 infection are synergistic and therefore their dual occurrence may fuel increased incidence of cancer of the cervix and AIDS. We therefore conducted a study to determine the association between cancer of the cervix and HIV-1.

Methods

The study was carried out in Ocean Road Cancer Institute, Dar-es-salaam, Tanzania between January and March 2007. A hospital-based case control design was used to study 138 cases and 138 controls. The cases were consenting women 18 years and above with histologically confirmed squamous cell carcinoma of the cervix, while the controls were consenting non-cancer adult women attendants or visitors. The participants were counselled and tested for HIV-1 and interviewed to assess risk factors for cancer of the cervix and HIV-1. Estimation of risk was done by computing odds ratios and confidence intervals. Confounding and interaction between the factors were assessed using logistic regression.

Results

HIV-1 prevalence was much higher among the cases (21.0%) than among the controls (11.6%). In logistic regression, HIV-1 was associated with cancer of the cervix (OR = 2.9, 95% CI = 1.4–5.9). Among the cases the mean age was lower for HIV-1 infected (44.3 years) than HIV-1 uninfected women (54 years, p = 0.0001).

Conclusion

HIV-1 infection is associated with invasive cancer of the cervix. Resource-constrained countries with a high burden of HIV-1 and cervical cancer should adopt a high-risk approach that targets HIV-1 positive women for screening of cervical cancer initially by utilizing HIV/AIDS resources.

Knowledge about cervical cancer risk factors, traditional health beliefs, and Pap testing among Vietnamese American women

INTRODUCTION

The objective of this paper was to examine knowledge about cervical cancer risk factors and traditional health beliefs in relation to Papanicolaou (Pap) testing among Vietnamese women.

METHODS

A population-based survey was conducted in Seattle (n<352, response rate=82%) during 2002.

RESULTS

The proportions of women who knew that older age, not getting regular Pap tests, and Vietnamese ethnicity are associated with an elevated cervical cancer risk were only 53%, 62%, and 23%, respectively. The majority (87%) incorrectly believed poor women's hygiene is a risk factor for cervical cancer. Approximately two-thirds (68%) of the women had received a Pap test during the preceding three years. Knowing that lack of Pap testing increases the risk of cervical cancer was strongly associated (p<0.001) with recent Pap smear receipt.

CONCLUSION

Our results confirm that Vietnamese women have lower levels of cervical cancer screening than non-Latina white women. Intervention programs addressing Pap testing in Vietnamese communities should recognize women's traditional beliefs while encouraging them to adopt biomedical preventive measures into their daily lives.

Cervical carcinoma and reproductive factors: Collaborative reanalysis of individual data on 16,563 women with cervical carcinoma and 33,542 women without cervical carcinoma from 25 epidemiological studies

The International Collaboration of Epidemiological Studies of Cervical Cancer has combined individual data on 11,161 women with invasive carcinoma, 5,402 women with cervical intraepithelial neoplasia (CIN)3/carcinoma in situ and 33,542 women without cervical carcinoma from 25 epidemiological studies. Relative risks (RRs) and 95% confidence intervals (CIs) of cervical carcinoma in relation to number of full-term pregnancies, and age at first full-term pregnancy, were calculated conditioning by study, age, lifetime number of sexual partners and age at first sexual intercourse. Number of full-term pregnancies was associated with a risk of invasive cervical carcinoma. After controlling for age at first full-term pregnancy, the RR for invasive cervical carcinoma among parous women was 1.76 (95% CI: 1.53-2.02) for > or => or =7 full-term pregnancies compared with 1-2. For CIN3/carcinoma in situ, no significant trend was found with increasing number of births after controlling for age at first full-term pregnancy among parous women. Early age at first full-term pregnancy was also associated with risk of both invasive cervical carcinoma and CIN3/carcinoma in situ. After controlling for number of full-term pregnancies, the RR for first full-term pregnancy at age <17 years compared with > or => or =25 years was 1.77 (95% CI: 1.42-2.23) for invasive cervical carcinoma, and 1.78 (95% CI: 1.26-2.51) for CIN3/carcinoma in situ. Results were similar in analyses restricted to high-risk human papilloma virus (HPV)-positive cases and controls. No relationship was found between cervical HPV positivity and number of full-term pregnancies, or age at first full-term pregnancy among controls. Differences in reproductive habits may have contributed to differences in cervical cancer incidence between developed and developing countries.

High-Risk Human Papillomavirus Detection and Related Risk Factors Among Pregnant and Nonpregnant Women in Mexico

BACKGROUND

Significant differences in human papillomavirus (HPV) prevalence between pregnant and nonpregnant women have been reported. Some studies suggest that physiological processes during pregnancy modify the host-immune response, increasing detectability of high-risk HPV infection as a result of viral reactivation. It remains uncertain, however, whether pregnancy has an effect on HPV DNA positivity as a result of a general lack of data and based on contradictory results found in previous epidemiologic studies. We conducted an epidemiologic study to identify differences in the prevalence of HPV infection between pregnant and nonpregnant women in Mexico. We also investigated the relationship of HPV DNA positivity with socioeconomic, gynecologic, and obstetric risk factors.

METHODOLOGY

We screened pregnant and age-matched nonpregnant women for high-risk HPV infection. The study population was clients of the family medicine healthcare services of the Mexican Institute of Social Security in Cuernavaca, Morelos, Mexico. A total of 274 pregnant and 1060 nonpregnant study participants were screened for the presence of high-risk HPV DNA in self-collected specimens by the Hybrid Capture 2 test (HC2; Digene Corp., Gaithersburg, MD).

RESULTS

High-risk HPV DNA was detected in 37.2% (95% confidence interval [CI], 31-43%) of pregnant women and in 14.2% (95% CI, 12-16%) of nonpregnant women. Combining both groups for the multivariate analysis, pregnancy was associated with an increased risk for HPV infection (odds ratio, 3.5; CI, 2.7-4.9).

CONCLUSIONS

Our results are consistent with other studies reporting increased high-risk HPV detection rates among pregnant women. HPV-positive status in pregnant and nonpregnant women appears to be influenced by age. The decrease in HPV positivity by number of pregnancies in both currently pregnant and nonpregnant women is consistent with a possible effect of immune protection as a result of earlier HPV infections. Despite lack of information about a woman's history of sexual behavior, these data support the hypothesis that an alteration of immunologic responses during pregnancy may be associated with an increased risk of HPV acquisition or reactivation.

The influence of smoking and other cofactors on the time to onset to cervical cancer in a southern European population

Cervical cancer is a complex and multifactorial disease. Although there are substantial data supporting the causative role of persistent human papillomavirus (HPV) infection in the development of cervical cancer, the complete course of the disease has never been completely understood. Several risk cofactors have been suggested with controversial results. Portugal has the highest incidence of squamous cell carcinoma (SCC) within western Europe and there are no known studies regarding the role of cofactors in SCC. The aim of our study was to evaluate the role of smoking, sexual behaviour, reproductive and contraceptive history, in the time-to-onset (TTO) of severe cervical lesions (HGSIL/SCC) in the Portuguese population. We verified that age of first sexual intercourse under 18 years (odds ratio (OR) 2.8), pregnancy (OR 2.9), first pregnancy under 21 years (2.6), number of pregnancies (OR 2.3-5.4) and parity (OR 1.9-5.7) are risk factors in the development of cervical neoplasia. Smoke exposure index (SEI) was significantly different (P=0.002) between cases and controls. Our results regarding time-to-onset demonstrate that smoking (P<0.001, log rank test), number of sexual partners (P<0.001, log rank test) and use of oral contraceptives (P<0.001, log rank test) are important determinants in the earlier onset of severe cervical lesions. Using this approach, our findings may help to clarify the role of smoking and other cofactors in the persistence and progression of cervical lesions.

Evaluation of tamoxifen in persistent or recurrent nonsquamous cell carcinoma of the cervix: a Gynecologic Oncology Group study

This study was undertaken to estimate the antitumor activity of tamoxifen in patients with persistent or recurrent nonsquamous cell carcinoma of the cervix. Furthermore, the nature and degree of adverse effects from tamoxifen in this cohort of individuals was examined. Tamoxifen citrate was to be administered at a dose of 10 mg per orally twice a day until disease progression or unacceptable side effects prevented further therapy. A total of 34 patients (median age: 49 years) were registered to this trial; two were declared ineligible. Thirty-two patients were evaluable for adverse effects and 27 were evaluable for response. There were only six grades 3 and 4 adverse effects reported: leukopenia (in one patient), anemia (in two), emesis (in one), gastrointestinal distress (in one), and neuropathy (in one). The objective response rate was 11.1%, with one complete and two partial responses. In conclusion, tamoxifen appears to have minimal activity in nonsquamous cell carcinoma of the cervix.

Cancer of the Uterine Cervix

HEALTH ISSUE: Cervical cancer is one of the most common malignant diseases of women; it is diagnosed in almost half a million women every year and half as many die from it annually. In Canada and other industrialized countries, its incidence has decreased due to cytology screening. However, invasive cases still occur, particularly among immigrant groups and native Canadian women. Although incidence of squamous cell carcinomas has decreased, the proportion of adenocarcinomas has increased because Pap cytology is ineffective to detect these lesions. KEY FINDINGS: In Canada, cervical cancer will cause an estimated 11,000 person-years of life lost. In most Canadian provinces, early detection is dependent on opportunistic screening. Primary prevention can be achieved through health education (sexual behavior modification) and vaccination to prevent infection from Human Papillomavirus (HPV). The initial results from vaccination trials are encouraging but wide scale use is more than a decade away. DATA GAPS AND RECOMMENDATIONS: Most cases of cervical cancer occur because the Pap smear was either false negative, was not done or not done often enough. Appropriate recommendations and guidelines exist on implementation of cytology-based programs. However, most Canadian women do not have access to organized screening. Further research is needed to 1) evaluate automated cytology systems; 2) define appropriate management of precursor lesions and 3) deliver definitive evidence of HPV testing efficacy in long-term follow-up studies with invasive cancer as an outcome and 4) provide Canadian data to justify augmenting or modifying current programs to use HPV testing in secondary triage of equivocal Pap smears.

TP73 alterations in cervical carcinoma

Infection with human papillomaviruses (HPV) is essential in the carcinogenesis of the uterine cervix. However, a complex interrelation between viral and cellular genes is necessary for cell-cycle control deregulation and development and progression of cervical cancer induction. The TP73 gene is localized in 1p36.3 band, which is often deleted by loss of heterozygosity (LOH) in human cancers. We analyzed the p73 cytosine thymine polymorphism and LOH in this locus by polymerase chain reaction restriction fragment length polymorphism in 134 DNA samples from biopsies of 67 primary untreated invasive cervix tumors and the corresponding peripheral blood. Genotype frequencies of 56.7% for homozygous genotype GC/GC and 43.3% for heterozygous genotype GC/AT were found. The presence of the GC/AT genotype in tumors was associated with lower age at menarche (P=0.039) and high parity (P=0.015). In 20.0% of DNA tumor samples, the AT allele was lost compared with their DNA normal blood pairs. The AT allele was conserved in women with high parity. This was not the case in the group with low parity, with 33.3% of patients showing loss of the AT allele in tumor DNA (P=0.041). These results suggest that TP73 genetic alterations may contribute to the genesis and/or progression of cervical carcinoma in an HPV-infected transformation zone under prolonged exposure to events related to pregnancy.

A population-based study on the risk of cervical cancer and cervical intraepithelial neoplasia among grand multiparous women in Finland

Previous studies suggest that high parity increases the risk of cervical cancer. We studied the risk of cervical cancer (CC) and cervical intraepithelial neoplasia (CIN3) in a Finnish cohort of grand multiparous (GM) women (at least five children) with low prevalence of sexually transmitted infections (STI). The Finnish Cancer Registry data revealed 220 CC and 178 CIN3 cases among 86 978 GM women. Standardised incidence ratios (SIR) were calculated from the numbers of observed and expected cases. Interval analyses by parity, age at first birth and average birth interval were done using multivariate Poisson regression. Seroprevalence of human papillomavirus (HPV) 16 and Chlamydia trachomatis was tested among 561 GM women and 5703 women with 2–4 pregnancies. The incidence among GM women was slightly above the national average for squamous cell carcinoma of cervix uteri (SIR 1.21, 95% CI 1.05–1.40) and CIN3 (1.37, 95% CI 1.17–1.58), but lower for adenocarcinoma (SIR 0.77, 95% CI 0.52–1.10). The seroprevalence of HPV16 and Chlamydia trachomatis among GM women was lower than in the reference population, except among those women who had their child under age 19. Age under 20 years at first birth increased the risk of CC and CIN3 especially in premenopausal GM women, while increasing parity had no effect. The small relative risks of CC and CIN3 among GM women in our study as compared to studies from other countries can be explained by the exceptionally low prevalence of STIs in Finnish GM women. The observed SIRs between 1.2 and 1.4 should be interpreted to represent increased risk attributable to grand multiparity. The increased incidence of CC and CIN3 among young GM women suggests causal association to HPV 16 and Chlamydia trachomatis infections.

Association between war and cervical cancer among Vietnamese women

Decades ago, cervical cancer was the leading form of cancer among women in both North Vietnam and South Vietnam. Currently, cervical cancer rates are considerably lower in the northern region of the country. We performed a case-control study to measure factors associated with the development of cervical cancer among Vietnamese women. Questionnaire-based interviews were conducted with 202 women in southern Vietnam and 97 women in northern Vietnam. Case subjects were women hospitalized with cervical cancer. Control subjects were women hospitalized with extrauterine neoplasms. Data were analyzed using logistic regression, and odds ratios for the development of invasive cervical cancer were measured. The development of invasive cervical cancer was significantly associated with military service by husbands during the Second Indochinese War and with parity status. Odds ratio for the development of cervical cancer among southern Vietnamese women whose husbands had served in the armed forces was 2.6 (95% CI = 1.2-5.5). Odds ratio for the development of cervical cancer among northern women whose husbands had served in the armed forces was 3.9 (95% CI = 1.5-10.4) if their husbands had been stationed in South Vietnam during the war years. Northern women whose husbands had served in the military experienced no significant increase in cervical cancer risk if their husbands had been stationed in North Vietnam during the war years. Geographic and temporal variation in cervical cancer rates among Vietnamese women was associated with the movement of soldiers. These findings may be useful for cervical cancer prevention efforts in Vietnam and in other countries.

Behavioural risk factors for cervical cancer from a prospective study in Khon Kaen, Northeast Thailand

Fifty seven cases of cancer of the cervix were identified within a cohort of 16,648 women enrolled in a cohort study of lifestyle and cancer in a rural population of Northeast Thailand. They were compared with 228 matched controls from the same cohort, with respect to demographic, behavioural and reproductive factors potentially associated with risk of the disease. Number of pregnancies and age at having first child were associated with the risk of cervical cancer, but in contrast to studies elsewhere, age at having first sexual intercourse, number of sexual partners and sexually-transmitted infections were not associated with risk. The lack of effect may be simply due to the small size of the study. But it is also likely that these aspects of female sexual behaviour are not very relevant in a relatively conservative rural population. These aspects may be investigated further in future, as new incident cancers are accrued into the cohort.

Human papillomavirus and risk factors for cervical cancer in Chennai, India: a case-control study

To evaluate the role of human papillomavirus (HPV) and other risk factors in the aetiology of invasive cervical carcinoma (ICC), we conducted a hospital-based case-control study in Chennai, Southern India. A total of 205 ICC cases (including 12 adenocarcinomas) and 213 frequency age-matched control women were included. HPV DNA in cervical cells was evaluated by means of a polymerase chain-reaction assay. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were computed by means of unconditional multiple logistic regression models. HPV infection was detected in all but one ICC cases and in 27.7% of control women (OR = 498). Twenty-three different HPV types were found. HPV 16 was the most common type in either cases or controls, followed by HPV 18 and 33. The association of ICC with HPV 18 and HPV 16-associated types was somewhat stronger than the one with HPV 16. Multiple HPV infections did not show a higher OR for ICC than single infections. Other than HPV infection, high parity (OR for >4 vs. </=2 births = 7.3), a woman's report of her husband's extramarital sexual relationships (OR = 10.0) and early menopause (OR for <45 vs. >/=45 years = 4.2) were significantly associated with ICC, also after restricting the analysis to HPV-positive cases and controls. Poor hygienic conditions were associated with an increased risk of HPV infection among control women but not with ICC risk among HPV-positive women. A vaccine against HPV 16 and 18 may be effective in more than three-quarters of ICC in the study area.

Prise en charge d’une néoplasie intra-épithéliale du col de l’utérus en cours de grossesse

Approximately 30% of women diagnosed with cervical cancer are in their childbearing years. Prenatal care provides an excellent opportunity for cervical cancer screening. The incidence of abnormal Pap smear has been reported in 5-8% of pregnant women. But we must know that Pap smears have cytologic modifications because of pregnancy. All abnormal smears have to be referred to colposcopic examination. The squamocolumnar junction is visualized in almost 100% of cases. The sensitivity of colposcopy is nearly 87% with complete concordance in 72.6%. Colposcopically directed biopsies have a good correlation with the final diagnosis with very minimal risks for both mother and fetus. The high rate of complications (hemorrhage, abortion, premature labor) and residual lesions in half of cases do not encourage conization during pregnancy. The final treatment is carried out after delivery. The only absolute indication for conization in pregnancy is to rule out microinvasive disease or make the diagnosis of invasive carcinoma when such a diagnosis will alter the timing of delivery but also when there is a no satisfactory colposcopy and a high-grade Pap smear. In these cases conization is performed for diagnostic and not therapeutic purpose. We must be aware of the high rate of loss of follow-up (6-33%).

The Epidemiology of Cervical Cancer

Cervical cancer is one of the most common neoplastic diseases affecting women, with a combined worldwide incidence of almost half a million new cases annually, second only to breast cancer. Basic and epidemiologic research conducted during the past 15-20 years have provided overwhelming evidence for an etiologic role for infection with certain types of sexually-transmitted human papillomavirus (HPV) as the primary cause of cervical cancer. The relative risks of cervical cancer following HPV infection as ascertained in case-control and cohort studies are among the highest in cancer epidemiology. The available evidence indicates that the HPV-cervical cancer association satisfies all relevant causal criteria for public health action. Other cervical cancer risk factors, such as smoking, parity, use of oral contraceptives, diet, other infections, and host susceptibility traits must be understood in the context of mediation of acquisition of HPV infection or in influencing events of the natural history of cervical neoplasia that occur following the establishment of a persistent HPV infection. Virtually all cervical carcinoma specimens contain HPV DNA, which suggests that HPV infection is a necessary cause of cervical neoplasia. This is the first instance in which a necessary cause has been demonstrated in cancer epidemiology--a realization that has obvious implications for primary and secondary prevention of this neoplastic disease.

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.

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.

Knowledge of cervical cancer risk factors among Chinese immigrants in Seattle

Chinese American immigrants are a growing part of the United States population. Cervical cancer is a significant cause of morbidity and mortality among Chinese Americans. Pap smear testing is less common in Chinese American immigrants than in the general population. During 1999, we conducted a community-based survey of Chinese American women living in Seattle. We assessed knowledge of cervical cancer risk factors and history of Pap smear testing along with socioeconomic and acculturation characteristics. The overall estimated response rate was 64%, and the cooperation rate was 72%. Our study sample included 472 women. Most cervical cancer risk factors were recognized by less than half of our participants. Factors independently associated with knowledge of cervical cancer risk factors included marital status, employment, and education. Respondents with the highest knowledge had greater odds of ever receiving a Pap smear, compared to those respondents with the lowest knowledge (OR 2.5; 95% CI: 1.1,5.8). Our findings suggest a need for increased recognition of cervical cancer risk factors among Chinese American immigrants. Culturally and linguistically appropriate educational interventions for cervical cancer risk factors should be developed, implemented and evaluated.

Cervical cancer risk as a predictor of Pap smear use in rural North Carolina

Risk for invasive cervical cancer is reported to be higher in rural areas than urban ones, and cervical cancer-related mortality is higher in rural women due to poorer utilization of preventive services and subsequent presentation at late stages of the disease. This cross-sectional study examined the relationship between prevalence of risk factors for cervical cancer and the degree of compliance with risk-appropriate screening guidelines for cervical cancer. Secondary data were analyzed for 614 women from Robeson County, NC, aged 40 and older, and of mainly rural and low socioeconomic status. High-risk status was determined by the presence of any of the following five risk factors: a history of more than two sexual partners, age at first sexual intercourse under 18 years, history of sexually transmitted disease, history of sexually transmitted disease in sexual partner(s), and smoking. Low-risk status was the absence of all factors. A high-risk participant was considered compliant if she had had at least three Pap smears in the 3 years prior to the interview, while a low-risk participant was considered compliant if she had had at least one Pap smear within the previous 3 years. Overall, 82% of the participants were at high risk for cervical cancer. However, only 41% of all participants were compliant with the risk-appropriate screening guidelines. Low-risk status was significantly associated with compliance with cervical cancer screening guidelines (adjusted OR = 6.7; 95% CI = 3.7 to 11.1, p = .0001). Findings in this study population suggest rural women at high risk for cervical cancer are less likely to be compliant with appropriate Pap smear screening guidelines, indicating the need to target educational programs.

Role of parity and human papillomavirus in cervical cancer: the IARC multicentric case-control study

BACKGROUND

High parity has long been suspected of being associated with an increased risk of cervical cancer, but previous analyses of this association have not taken the strong effect of human papillomavirus (HPV) into account. To assess the role of reproductive factors in the progression from HPV infection to cancer, we did a pooled analysis including only HPV-positive women.

METHODS

We pooled data from eight case-control studies on invasive cervical carcinoma (ICC) and two on in-situ carcinoma (ISC) from four continents. 1465 patients with squamous-cell ICCs, 211 with ISCs, 124 with adenocarcinomas or adenosquamous ICCs, and 255 control women, all positive for HPV DNA by PCR-based assays, were analysed. We calculated pooled odds ratios by means of unconditional multiple logistic regression models, and adjusted them for sexual and non-sexual confounding factors. The 95% CI were estimated by treating the odds ratio as floating absolute risk.

FINDINGS

We found a direct association between the number of full-term pregnancies and squamous-cell cancer risk: the odds ratio for seven full-term pregnancies or more was 3.8 (95% CI 2.7-5.5) compared with nulliparous women, and 2.3 (1.6-3.2) compared with women who had one or two full-term pregnancies. There was no significant association between risk of adenocarcinoma or adenosquamous carcinoma and number of full-term pregnancies.

INTERPRETATION

High parity increases the risk of squamous-cell carcinoma of the cervix among HPV-positive women. A general decline in parity might therefore partly explain the reduction in cervical cancer recently seen in most countries.