Risk factors associated with uterine cervical cancer in Korea: a case-control study with special reference to sexual behavior

Screening for cervical carcinoma in HIV-infected women: Analysis of main risk factors for cervical cytologic abnormalities

AIM

The aim of this study was to identify potential predictive factors for cervical disease in women with HIV and to evaluate adherence during follow-up to cervical cancer screening.

METHODS

In order to identify the independent role of factors associated with the presence of a cervical abnormality, all of the variables showing in univariate analyses a potential association with the outcome variable (presence of cervical abnormalities) were entered into a multivariate logistic regression model, along with age at first visit to our center, and age at diagnosis.

RESULTS

A total of 540 HIV-positive women who received screening for cervical cancer during the first year after their first visit to our center were included in the analysis; 423 (78.3%) had normal cytology and 117 (21.7%) had cytological abnormalities, classified as follows: 21 atypical squamous cells of undetermined significance (17.9%); 51 low-grade squamous intraepithelial lesions (43.6%); 41 high-grade squamous intraepithelial lesions (35.0%); and four cervical cancers (3.4%). In our study, women with more than two previous pregnancies were significantly associated with a lower risk of cervical cytological abnormalities compared to the other women. Women with CD4+ levels of 200-499/mm³ had a higher risk of developing cervical cytological abnormalities compared to those with a CD4+ level > 500/ mm³ .

CONCLUSION

In summary, management of HIV-positive women must be modeled on HIV-clinical status, CD4+ cell count, drug regimen, and adherence to follow-up, relying on the cooperation of highly qualified professionals. In HIV-positive women, an adequate screening and follow-up allows for a reduced occurrence of advanced cervical disease and prevents recourse to invalidating surgical interventions.

Multiple Sexual Partners as a Potential Independent Risk Factor for Cervical Cancer: a Meta-analysis of Epidemiological Studies

It's known that having multiple sexual partners is one of the risk factors of human papillomavirus (HPV) infection which is a major cause of cervical cancer. However, it is not clear whether the number of sexual partners is an independent risk factor for cervical cancer. We identified relevant studies by searching the databases of MEDLINE, PubMed and ScienceDirect published in English from January 1980 to January 2014. We analyzed those studies by combining the study-specific odds ratios (ORs) using random-effects models. Forty-one studies were included in this meta-analysis. We observed that the number of sexual partners was associated with the occurrence of non-malignant cervical disease (OR=1.82, 95%CI 1.63-2.00) and invasive cervical carcinoma (OR=1.77, 95%CI 1.50-2.05). Subgroup analyses revealed that the association remained significant after controlling for HPV infection (OR=1.52, 95%CI 1.21-1.83 for non-malignant disease; OR=1.53, 95%CI 1.30- 1.76 for invasive cervical carcinoma). We found that there was a non-linear relation of the number of sexual partners with both non-malignant cervical disease and invasive cervical carcinoma. The risk of both malignant and non-malignant disease is relatively stable in women with more than 4-7 sexual partners. Furthermore, the frequency-risk of disease remained significant after controlling for HPV infection.The study suggested that having multiple sexual partners, with or without HPV infection, is a potential risk factor of cervical cancer.

Alcohol consumption and persistent infection of high-risk human papillomavirus

Alcohol consumption is a possible co-factor of high-risk human papillomavirus (HR-HPV) persistence, a major step in cervical carcinogenesis, but the association between alcohol and continuous HPV infection remains unclear. This prospective study identified the association between alcohol consumption and HR-HPV persistence. Overall, 9230 women who underwent screening during 2002-2011 at the National Cancer Center, Korea were analysed in multivariate logistic regression. Current drinkers [odds ratio (OR) 2·49, 95% confidence interval (CI) 1·32-4·71] and drinkers for ⩾5 years (OR 2·33, 95% CI 1·17-4·63) had a higher risk of 2-year HR-HPV persistence (HPV positivity for 3 consecutive years) than non-drinkers and drinkers for <5 years, respectively (vs. HPV negativity for 3 consecutive years). A high drinking frequency (⩾twice/week) and a high beer intake (⩾3 glasses/occasion) had higher risks of 1-year (OR 1·80, 95% CI 1·01-3·36) HPV positivity for 2 consecutive years) and 2-year HR-HPV persistence (OR 3·62, 95% CI 1·35-9·75) than non-drinkers. Of the HPV-positive subjects enrolled, drinking habit (OR 2·68, 95% CI 1·10-6·51) and high consumption of beer or soju (⩾2 glasses/occasion; OR 2·90, 95% CI 1·06-7·98) increased the risk of 2-year consecutive or alternate HR-HPV positivity (vs. consecutive HPV negativity). These findings suggest that alcohol consumption might increase the risk of cervical HR-HPV persistence in Korean women.

Attributable fraction of tobacco smoking on cancer using population-based nationwide cancer incidence and mortality data in Korea

Background

Smoking is by far the most important cause of cancer that can be modified at the individual level. Cancer incidence and mortality rates in Korea are the highest among all Asian countries, and smoking prevalence in Korean men is one of the highest in developed countries. The purpose of the current study was to perform a systematic review and provide an evidence-based assessment of the burden of tobacco smoking-related cancers in the Korean population.

Methods

Sex- and cancer-specific population-attributable fractions (PAF) were estimated using the prevalence of ever-smoking and second-hand smoking in 1989 among Korean adults, respectively, and the relative risks were estimated from the meta-analysis of studies performed in the Korean population for ever-smoking and in the Asian population for passive smoking. National cancer incidence data from the Korea Central Cancer Registry and national cancer mortality data from Statistics Korea for the year 2009 were used to estimate the cancer cases and deaths attributable to tobacco smoking.

Results

Tobacco smoking was responsible for 20,239 (20.9%) cancer incident cases and 14,377 (32.9%) cancer deaths among adult men and 1,930 (2.1%) cancer incident cases and 1,351 (5.2%) cancer deaths among adult women in 2009 in Korea. In men, 71% of lung cancer deaths, 55%–72% of upper aerodigestive tract (oral cavity, pharynx, esophagus and larynx) cancer deaths, 23% of liver, 32% of stomach, 27% of pancreas, 7% of kidney and 45% of bladder cancer deaths were attributable to tobacco smoking. In women the proportion of ever-smoking-attributable lung cancer was 8.1%, while that attributable to second-hand smoking among non-smoking women was 20.5%.

Conclusions

Approximately one in three cancer deaths would be potentially preventable through appropriate control of tobacco smoking in Korean men at the population level and individual level. For Korean women, more lung cancer cases and deaths were attributable to second-hand than ever-smoking. Effective control programs against tobacco smoking should be further developed and implemented in Korea to reduce the smoking-related cancer burden.

Genotypic prevalence of human papillomavirus infection during normal pregnancy: a cross-sectional study

AIM

Genital human papillomavirus (HPV) infection is a necessary factor in most cases of cervical cancer, but malignant transformation requires the presence of additional cofactors such as pregnancy. Little is known about the effect of pregnancy on genital HPV carriage. We therefore analyzed the prevalence and genotypic patterns of genital HPV infections in normal pregnancies.

METHODS

The prevalence of HPV infection was measured in 960 consecutive normal pregnant or post-partum women by HPV-DNA chip analysis of cervical swabs. Data were analyzed by trimester and adjusted for sociodemographic, reproductive and reported sexual history.

RESULTS

The overall prevalence of HPV infection in the population was 24.3%. High-risk HPV genotypes were detected in 68.2% of infected subjects, including HPV 16 (18.7%), 39 (16.4%), 53 (10.1%), and 56 (9.4%). High-risk HPV genotypes were significantly more prevalent in the second trimester (23.8%) compared with the other periods (first trimester, 13.2%; third trimester, 17.4%; post-partum, 15.1%; P = 0.010). However, the high-risk HPV genotypes 16 or 18 were detected most frequently in the third trimester (7.2%) as compared to the other periods (first trimester, 2.9%; second trimester, 5.2%; post-partum, 2.1%; P = 0.03). After adjusting for confounding variables, overall HPV infection (odds ratio = 1.84, 95% confidence interval = 1.24-2.75) and high-risk HPV genotypes (odds ratio = 1.94, 95% confidence interval = 1.23-3.05) were significantly more common in the second trimester.

CONCLUSION

The second trimester may be the most vulnerable period in high-risk HPV infections, which necessitates future investigations.

Mild obesity, physical activity, calorie intake, and the risks of cervical intraepithelial neoplasia and cervical cancer

Objective

We investigated whether obesity, physical activity, and calorie intake are associated with the risks of cervical intraepithelial neoplasia (CIN) and cervical cancer.

Methods

We enrolled 1125 women (age, 18–65 years) into a human papillomavirus cohort study established from 2006 to 2012. Multinomial logistic regression models were used to estimate crude and multivariate odds ratios (ORs) and the corresponding 95% confidence intervals (95% CIs), and to assess whether body mass index (BMI), height, weight, total calorie intake, and physical activity were associated with the risks of CIN and cervical cancer.

Results

Cervical cancer risk was positively associated with BMI and inversely associated with physical activity. When compared with women with a normal BMI (18.5–23 kg/m²), the multivariate ORs (95% CIs) for those overweight (23–25 kg/m²) and mild obesity (≥25 kg/m²) were 1.25 (0.79–2.00) and 1.70 (1.10–2.63), respectively. When compared with women with the lowest tertile of physical activity (<38.5 MET-hours/week), the ORs (95% CIs) for cervical cancer were 0.95 (0.61–1.48) and 0.61 (0.38–0.98) for women with medium physical activity (38.5–71.9 MET-hours/week) and those with high physical activity (72 MET-hours/week), respectively (p for linear trend  = 0.03). The CIN2/3 risk was inversely associated with physical activity after adjustment for confounders. Compared with women with low physical activity (< 38.5 MET-hours/week), the ORs (95% CIs) for CIN2/3 were 0.64 (0.40–1.01) and 0.58 (0.36–0.93) for the medium and high physical activity groups, respectively (p for linear trend  = 0.02). Total calorie intake was not statistically associated with the risks of CIN and cervical cancer after adjustment for confounders.

Conclusion

Our results indicate that in addition to screening for and treatment of CIN, recommendations on the maintenance of an appropriate BMI with an emphasis on physical activity could be an important preventive strategy against the development of cervical cancer.

Multiple HPV infection in cervical cancer screened by HPVDNAChip

This study determined the distribution of high-risk HPV type infection in cervical cancer using newly developed oligonucleotide chips (HPVDNAChips). The study subjects included 80 cases of cervical neoplasia and 746 controls with a normal Pap smear. For HPV genotyping, the commercially available HPVDNAChips was used. The risk of cervical cancer was increased in women with a family history of cervical cancer (adjusted OR=2.3, 95% CI: 0.92-6.17) and in smokers (adjusted OR=3.2, 95% CI: 1.45-7.06). There was also a trend of increased risk with the number of full term pregnancies (P(for trend)<0.001). There were only 7.2% (54 of 746) infected high-risk HPV types in the control, whereas 54.5% (six of 11) and 76.5% (52 of 68) were infected in the CIN and cervical cancer, respectively. Multiple HPV infection was observed in 0.5% (three of 592) of the control group but in 9.1% (seven of 77) of cases. Multivariate analysis revealed that subjects infected with multiple HPV types had a 31.8-fold (95% CI: 7.50-134.75) higher risk of cervical cancer, while the single HPV type had a 19.9-fold increased risk (95% CI: 10.90-36.18) (P(for trend)<0.001). These results show that the detection and typing of HPV infection by HPVDNAChip can be a useful in clinical applications because it provides information on multiple infections and the types of HPV in addition to HPV infection status.

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.

Tailoring clinical management practices to meet the special needs of adolescents: sexually transmitted infections

Sexually transmitted infections are a major health risk to all sexually active adolescents and improving clinical management for this age group is of major importance. Currently, adolescents are managed in the same way as adults. This paper summarizes recommendations by the World Health Organization that services be more responsive to adolescent concerns about confidentiality, risk assessment be more attuned to their sexual behavioral patterns, and services be tailored to give more time for counseling, assessment of stage of maturity and continuity of reproductive health care.

Co-factors related to the causal relationship between human papillomavirus and invasive cervical cancer in Honduras

BACKGROUND

A case-control study was conducted in Honduras to identify co-factors in the carcinogenic pathway by which human papillomavirus (HPV) causes invasive cervical cancer.

METHODS

Ninety-nine cases aged 23-65 (median 47) years participated. Two controls were matched to each case by age and clinic where they first presented for cytological screening; controls had no cervical abnormalities. Information on risk factors was obtained by personal interviews in the clinics regarding sociodemographic, reproductive and behavioral characteristics. Human papillomavirus was detected in cervical scrapes by general primer-mediated polymerase chain reaction (PCR) followed by sequence analysis to identify the different types present.

RESULTS

All cases had squamous cell tumours and most were FIGO (International Federation of Gynecologists and Obstetricians) class II or higher; HPV was strongly associated with cervical cancer (odds ratio [OR] = 7.66, 95% CI : 3.88-15.1). Among HPV-positive women, dose-response relationships were observed for education, age at first intercourse and exposure to wood smoke that persisted after adjustment for previous screening. Among HPV-negative women, the number of sexual partners and parity were associated with cervical cancer. The protective effect of previous cytological screening operated independently of HPV.

CONCLUSIONS

Our findings speak for the powerful role that both primary and secondary education plays in fostering a lifestyle that reduces the risk of invasive cervical cancer. The data suggest that important elements of such a lifestyle include later age at first sexual intercourse, a limited number of pregnancies, greater likelihood of undergoing cytological screening and reduced exposure to carcinogens in the household environment.

Management of cervical cancer in pregnancy

Carcinoma of the cervix is the most common gynecologic cancer found during pregnancy. Management and treatment of this condition depend on cancer stage, estimated gestational age, and ethical, religious, and personal desires. Review of the medical literature in English from 1965 to 1998 is presented with recommendations for management.

Complaints and complications in pregnancy: a study of ethnic Norwegian and ethnic Pakistani women in Oslo

OBJECTIVES

To describe the pattern of complaints and complications in pregnancy among ethnic Norwegian and ethnic Pakistani women in Oslo in order to modify antenatal care services.

DESIGN

A cross-sectional study of hospital patients conducted in community hospitals in Oslo, Norway. A total of 137 obstetrical patients, 66 ethnic Pakistani and 71 ethnic Norwegian women were included in the study. Medical complications and subjective reported physical complaints during pregnancy were the main outcome measures.

RESULTS

Among the ethnic Pakistani women complications were more common and the risks were higher for gestational diabetes [crude odds ratio (OR) = 5.6, 95% confidence interval (CI) = 1.5-20.5), intrauterine growth retardation (crude OR = 5.0, 95% CI = 1.4-18.8), hyperemesis gravidarum (crude OR = 3.7, 95% CI = 1.1-12.2) and anaemia (crude OR = 10.2, 95% CI = 3.3-31.4). The frequency of congenital malformations (p = 0.048, OR not calculated) were also higher. Among the ethnic Norwegian women the frequency of subjective reported physical complaints were more common and the risks were higher for pelvic girdle pain (crude OR = 0.4, 95% CI = 0.2-0.8) and exhaustion (crude OR = 0.2, 95% CI = 0.04-0.1). Infections such as hepatitis and tuberculosis only occurred in the Pakistani study group.

CONCLUSION

This study indicates that health personnel delivering antenatal care to women of Pakistani origin need to be watchful for the following conditions: gestational diabetes, hyperemesis gravidarum, early diagnosis of the type of anaemia, fetal malformations and infections like hepatitis and tuberculosis. In addition, a correct diagnosis of intrauterine growth retardation is important. Among ethnic Norwegian women pelvic girdle pain and exhaustion were common complaints.