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Indian Journal of Cancer
Medknow Publications on behalf of Indian Cancer Society
ISSN: 0019-509X EISSN: 1998-4774
Vol. 40, Num. 1, 2003, pp. 15-22

Indian Journal of Cancer, Vol. 40, No. 1, (January - March 2003) , pp. 15-22

Review Article

A Survey on Risk Factors Associated with Cervical Cancer

Juneja A, Sehgal A,* Mitra AB,* Pandey A

Institute for Research in Medical Statistics (ICMR), Ansari Nagar, New Delhi - 110029, India; and *Institute of Cytology and Preventive Oncology (ICMR), Maulana Azad Medical College, BSZ Marg, New Delhi - 110002, India.
Correspondence to: Atul Juneja. E-mail: atul_juneja@hotmail.com

Code Number: cn03002

ABSTRACT

Carcinoma of the cervix is one of the leading malignancies in the developing countries including India. In view of this health care program might have to be redefined. Most of the data are available from the developed countries, which rely mainly on cytology screening on regular basis. This however may not be feasible in developing countries because of various constraints. Thus alternative approaches are needed based on risk reduction modalities. This article while dealing with the control approaches based on secondary prevention, reviews several risk factors associated with cervical cancer. The various articles were approached through Medline search including cross-references. The important life styles associated with cervical cancer and which are amenable to primary prevention strategies through health education, behavioral interventions, legislative approaches and modifying the health care seeking behavior were identified through the review process. These factors mainly pertain to early sexual debut, multiple sexual partners, menstrual hygiene and unprotected sex. Role of male partners has also been delineated in the process of cervical carcinogenesis. These factors are essentially conducive to the transmission of an etiological agent; the high-risk types human papillomaviruses, the more proximal cause in the web of causation. Barrier method of contraception and prophylactic vaccine in future could help to check the transmission of the virus. Role of smoking and oral contraceptives has also been discussed. Till the facilities for mass scale screening are developed in developing countries the primary prevention approaches could certainly help to check the incidence of the disease.

Key Words: Cervical cancer, Cervical neoplasia, Cytology screening, Primary prevention.

Introduction

There has been a tremendous change in the demographic profile of the country. The birth and death rates have declined and the life expectancy of birth has also increased to 62 years as a result of betterment in health services. The increase in the expectation of life has brought about the change in the disease pattern of the population. In the midst of already existing communicable diseases, non-communicable disease like cancer has become a major cause of morbidity. Realizing the threat of cancer in a developing country like India, cancer control activities got due attention. Realizing the importance of this disease, Indian Council of Medical Research (ICMR) initiated a network of cancer registries under National Cancer Registry Programme (NCRP) in December 1991 to establish the database of magnitude of problem of cancer in different parts of the country. This move also recognized the need to augment and strengthen the existing registries. In the process, Bombay Cancer Registry under Indian Cancer Society, which has been providing data on cancer incidence since 1963 also became part of National Cancer Registry Programme. The population based cancer registries in India are working on active system of registration. These are based at Bangalore, Bhopal, Chennai, Delhi, Mumbai and rural registry at Barshi Maharashtra.These registries which represent different parts of the country are providing incidence and mortality data on cancer according to different factors. In addition there are hospital based cancer registries at Chandigarh, Dibrugarh and Trivandrum, which provide information mainly on relative frequencies of various cancers to help the planners to prioritize the control measures. The quality control for data collection and validation procedures is based on the international standards. The Indian data as available from NCRP is represented in the Cancer Incidence in five Continents published by International Agency for research in Cancer.1 As per the information generated through this programme, the cancer of the uterine cervix and the breast are the leading malignancies seen in Indian women where as tobacco related cancers are dominating in males.2 In view of the natural history of the cancer of the uterine cervix and availability of effective screening technique tool-PAP Test, the cancer of the uterine cervix gets priority in terms of control activities.

Squamous cell carcinomas usually arise from the squamocolumnar junction of the cervix and preceded by precancerous stages CIN I, CIN II and CIN III, (Cervical intra epithelial neoplasia) When abnormal cells occupy lower one third of the epithelium, the cytological reporting is termed as CIN I where as it falls in the category of CIN II when half of the total thickness is occupied by abnormal cells. When neoplastic cells replace the entire thickness of epithelium except the basement membrane, the stage is cytologically reported as CIN III (Severe Dysplasia and CIS). Invasive carcinomas occur when malignant epithelial cells break through the basement membrane and invader the stroma, continued growth results in visible lesions that involve more of tissues.3,4 The disease in stage CIN III and micro invasion can be easily diagnosed by exfoliative cytology and colposcopy. A leading study from Canada revealed that the disease in the in situ stage (CIN III), on an average takes about 10-12 years to enter in the invasive stage i.e. the time gap between detectable pre clinical phase and the clinical phase is quite long so that it provides enough opportunity to administer management when complete cure is possible.5 Hence it is justified to keep the cervical cancer as one of the priority areas for cancer control activities.

In view of the natural history of the disease, cervical cytology screening continues to be the main stay for the control of cervical cancer. The treatment of disease in its pre clinical phase will result in higher cure rate than if a disease is permitted to progress to a higher grade. Exfoliative cytology in spite of certain limitations, is an efficient method to detect the disease in pre invasive stage. Various studies have demonstrated reduction in morbidity and mortality from the disease.6 The situation in developing country is entirely different. There is no organized screening activity because of lack of resources including trained manpower. It has been accepted that there are primary health care deficiencies, as a result there cannot be referral system networking for cervical cancer screening for years to come. Even when the disease is detected in preinvasive stage there is no system to recall the patient for further investigation and treatment. The facilities for treating the precursors are also limited. In a country like India, the screening is only institution based and caters to a limited group. Hence there is there is need to look at the alternate strategies for mass screening.

In view of the logistic difficulties of cytological screening, alternate strategies have been advocated for developing countries. One of the strategies is based on the down staging of the disease by visual inspection of cervix.7,8 It has also been demonstrated that paramedical health workers could be trained to pick abnormal cervix.9,10 Visual inspection of cervix by application of acidic acid (VIA) is another approach for cervical cancer screening, where in addition to detecting early stage cancer, even pre cancerous lesions can also be picked up. This technique helps to identify changes in the transformation zone. It has been demonstrated in Indian settings and has yielded encouraging results. The high false positivity is matter of concern with this approach.7,11

The focus of screening is now shifting towards HPV testing in screening programs. Recent studies have reported HPV testing to be highly sensitive for detecting high-grade lesions.12 An effort has been made to study the HPV screening in Indian rural settings, the results confirm to the studies conducted in West.13 It has to be mentioned that the HPV testing in conjunction with Pap smear would again be non-economical affair for a setting with limited resources. However the strategy could be employed for institutional based screening. There is also need to consider inducting primary prevention module into the control programme. Considering the above mentioned facts it becomes very important to review the various studies that evaluated the risk factors associated with cervical cancer in different parts of the world and the scenario in the Indian context. This would help to formulate the strategies for the control of cervical cancer in India and other developing countries.

The present paper aims to review various studies of risk factors associated with the development of cervical cancer or carcinoma in situ (CIN III) in the developed and developing countries including India. An exhaustive search through Medline was carried out to reach at the various articles (published in English) related with various issues of screening and risk factors of cervical cancer. The articles were further cross-referred based on the Medline search. This included the classical papers, which formed the basis of the research on cervical cancer. Different relevant reports were procured from the libraries.

The studies on risk factors of cervical cancer were available since early seventies.14,15 Most of the studies recruited invasive cancers reporting to cancer clinics. No information was available for early cancerous or pre cancerous lesions (CIN I-III). The Institute of Cytology and Preventive Oncology (ICMR) New Delhi launched the first study, involving pre cancerous and early cancerous lesions in 1976. The study was first of its kind in India since it had recruited the subjects based on the cytology screening program carried out through the gynecology departments of major hospitals of the Delhi. The study examined the biological behaviour of precancerous lesions and the effect of certain sociodemographic and biological factors on progression of dysplasia to higher grades.16,17 The study was under the strict supervision of the scientific advisory committee. Various modifications were incorporated in the study based on the recommendations of the committee from time to time. The study was carried out in different phases and segments. In one of the segments, women revealing severe dysplasia and malignancy and further confirmed on biopsy were considered for case control comparison (WHO Classification was used for cytological diagnosis). Indepth information on various socidemographic factors, sexual behaviour, obstetric, menstrual and hygienic practices was elicited by the trained field worker on cases as well as controls to carry out the risk factor analysis. Women revealing normal or inflammation in cytology during twice in a month were recruited as controls. The results of the study have already been published.18,19 The results have been discussed along with other Indian studies in relation to the studies carried out in the developed world.

Sociodemographic factors

Data from the cancer registries indicate that more than 75% of cervical cancers develop in women above the age of 35 years.20 Most of the studies in developing countries indicate that average age of women with CIS or CIN III was between 35 to 44 years. The age parameter defines a `high risk' group relevant for the screening activities and providing health care facilities. It has been observed that that incidence of cervical cancer varies widely according to the geographic distribution. The highest rates have been reported from Latin America and low rates are observed in US whites and Jewish women in Israel. It has also been reported that women belonging to the lower social class are at much higher risk of development of cervical cancer. A recent study analyzed 127 low and medium developed countries where the rates varied from 3 to 61 per 100,000 females, identified geographical area and religion as the independent factors associated with the cervical cancer rates.21 The rates due to racial differences are also considered; the magnitude of the risk in black diminished when adjusted for socio economic status.22 Various studies have tried to analyze the variables associated with low socio economic status (education, income etc.) with the other life style practiced by them such as sexual and hygienic practices. In most of the studies low socio economic status has been observed to be the confounding factor.23

Sexual behavior

Domenico Rigoni-Stern in the middle of 19th century, who was an Italian Chief Physician of Verona Hospital and an instructor at University of Padua, first raised the issue of relationship of cervical cancer and marriage. He had observed for the first time that more uterine cervical cancer is found in married than unmarried based on mortality records. The relationship of cervical cancer with sexual behavior is supported by the fact that disease is rare in nuns.24,25 The first review of literature on the risk factors associated with sexual behavior was published in 1967, which reviewed nine studies.26

According to Martin the epidemiology of cervical neoplasm is based on three fundamentals, which are (i) near absence of neoplasms among nuns (ii) Near absence of neoplasms among other species other than humans, (iii) Extremely low incidence of disease among virgins. The main factors explored were early age at marriage, marital dissolution and remarriage. Rotkin also presented a review of different studies related with sexual behaviour in the process of cervical carcinogenesis.27 In all the studies the percentage of women having married before 20 years was significantly higher than controls. The studies clearly demonstrated that early coitus, marital dissolution and remarriage occur more frequently in cases than controls. Studies conducted in 1990s have highlighted early age at consummation of marriage as an important risk factor after adjusting for confounding variables.28-30 Attempts have also been made to study the risk patterns in cancer cervix in Indian situation. The first major study was carried out from 1960-63 in Agra.14 The study suggested that risk of development of cervical cancer increased with the onset of sexual activity. The results revealed that average age of women was 13.6 years for cases of cancer cervix where as it was 15.6 years for the control group. Jayant has also shown through the age cohort analysis that incidence of cervical cancer shows a decline if the age of marriage increases.31 In depth studies were carried out in the city of Bombay to identify role of sexual risk factors.15 It was observed that risk factors associated were of the same order as prevailing in the developed countries. Recent Indian studies also have also been made to study the risk patterns in cancer cervix in Indian situation. The first major study was carried out from 1960-63 in Agra.14 The study suggested that risk of development of cervical cancer increased with the onset of sexual activity. The results revealed that average age of women was 13.6 years for cases of cancer cervix where as it was 15.6 years for the control group. Jayant has also shown through the age cohort analysis that incidence of cervical cancer shows a decline if the age of marriage increases.31 In depth studies were carried out in the city of Bombay to identify role of sexual risk factors.15 It was observed that risk factors associated were of the same order as prevailing in the developed countries. Recent Indian studies also highlighted sexual behavior as an important contributing factor in the process of cervical carcinogenesis.32,33

Multiple sexual partners have also been the focus of attention of researchers as regards cervical cancer is concerned. The odds ratios ranged from 1.6-2.9 for the different studies reviewed by Rotkin. Based on the lead provided by the earlier studies, the research on sexual behavior continued in 1980's with focus on multiple contacts and Human Papillomavirus. The risk associated with 10 or more partners has been reported to be nearly three to four times higher than associated with one partner. The population attributable risk that can be associated to having two or more partners is approximately 36%.34,35 It has also been hypothesized that age at first coitus and number of sexual partners may be correlated hence attempts have also been to study their independent effect. Some of the studies have found independent effect of early age at marriage and multiple sexual partners.34-36 The risk of development of cervical cancer is elevated by 2 to 4 times if a women reports having more than one contact.26,37-39 The study by Brinton et al (1987) has a special significance because it included five geographical areas reporting to comprehensive cancer patient data system. To ensure proper representation of the population into sample, different racial groups were also included.

Attempts have also been made to study the role of multiple sexual partners in Indian situation by providing specialized training to the interviewers.40 Indian study conducted by ICPO (ICMR) highlighted extramarital relations (more than one partner) as significant variable in the development of high-grade lesion (sev dysplasia and above). (Ph.D. Thesis by A. Juneja, MD University Rohtak 1998-unpublished). It is important to mention that Indian studies did not include Human Papillomavirus in the analysis because of the lack of availability of the data on substantial number of cases for subjecting to indepth multi variate analysis. A limited analysis has revealed that the magnitude of odds ratios associated with sexual promiscuity and age of onset of sexual activity diminished when adjusted with status of HPV 16/18.41

Male behaviour

The risk of cervical cancer is influenced not only by woman's sexual behaviour but also by male behaviour. This hypothesis is based on the observations that there have been clusters of cervical and penile cancers and husbands of cervical cancer patients reported significantly more sexual partners.42 Poor penile hygiene of male partners has also been hypothesized as a risk factor for cervical cancer. The role of male behaviour in the genesis of cervical cancer was also examined in India. It was observed that risk of cervical cancer was about three times higher in women whose husbands reported sexual contacts with more than one woman during their lives other than wife. The results were adjusted for possible confounding factors.43 Hence the control strategies should also focus on male partners.

Menstrual/Reproductive/Hygienic factors

Attempts have also been made to study the relationship of cervical cancer with the age at menarche or menopause but it did not result in any statistical significance.27,30,34,44 The study carried out by ICMR also did not get any significance with the age of menarche.19 The type of material used is one of the important components associated with menstrual practice and has a direct concern with menstrual hygiene. Some of the studies carried out in west did not reveal any association between type of material and cervical neoplasia.45,46 The Indian study revealed that risk associated with the use of unclean cloth was 2.5 fold higher for the development of CIN III and malignancy as compared to the use of clean cloth or use of sanitary napkins. The factor remained statistically significant even after adjustment with other factors such as age, age at marriage, promiscuity and education, thus highlighting the importance of menstrual hygiene. It was observed that if any of the deliveries were conducted by untrained personnel (untrained dai) the women were at significantly higher risk of development of severe dysplasia and malignancy (CIN III) further emphasizing the role of hygiene. Women who abstained for less than forty days after delivery were also at elevated risk of development of disease highlighting the importance of this social practice. The odds ratios were adjusted for other obstetric practices, age at Ist pregnancy, education etc18,47 A very recent study in Mali also highlighted the use of home made napkins as a statistically significant risk factor in the development of cervical cancer. It is important to mention that poor hygiene was observed to be a co factor for cervical cancer with prevalent HPV infection.48 A report from WHO also suggests genital hygiene to be an important component associated with cervical neoplasia.49 These factors may not be of relevance in the developed countries. Abstinence from sex during periods as a factor in the process of cervical carcinogenesis has not been studied in the reports from the developed countries. Indian study also did not reveal any important finding for this variable.19

The role of multi parity has also been explored in the development of cervical cancer. It was hypothesized that multi parity could be one of the confounding variables. This variable is highly correlated with other marital factors. However some of the recent studies have revealed multiparty to be an independent risk factor.28,29,50

Frequency of sexual contact

The role of frequency of sexual contact on the risk of development of cervical is a difficult area of research, yet efforts have been in this direction to explore this sensitive variable. Earlier studies carried out did not reveal any statistical significance of enhanced frequency of sexual intercourse.26,27,44 The research on this aspect still continued because of hypothesis of association of sexual behavior with cervical cancer. The study by Herrero et al (1990) stated that frequency of coitus was a significant factor only for women reporting multiple exposures before 20 years supporting the hypothesis of vulnerable cervix. An attempt was also made to study this sensitive parameter in Indian situation. The frequency of contact did not emerge as a significant variable through a multiple logistic model after adjusting for possible confounders such as age, age at consummation of marriage, extramarital affairs.19 The recent studies are not evaluating this parameter possibly for the reasons mentioned above.

Family planning practices

Several investigations have studied the effect of different contraceptives practices on the risk of cervical cancer. One of the most common practices adopted for family planning is the use of oral contraceptives particularly in West. Recent investigations have raised concern for the long term users. Majority of the studies have revealed high risk of cervical neoplasia with increasing use of pill.45 Recent studies are focused on interactive effect oral contraceptive and HPV infection.29,51 Barrier method of contraception has been recommended as the preventive measure for cervical cancer possibly because it offers against some of the STDs. Very limited information was available from Indian studies on the role of contraceptive methods in the development of cervical cancer. In one of the studies the cases reporting OC use were too little for subjecting them to statistical analysis. However protective effect was reported in relation to the use of barrier method of contraception and (Ph.D. Thesis by A. Juneja, MD University Rohtak 1998-unpublished).

Smoking

Tobacco use has also been considered as an important candidate responsible in the process of cervical carcinogenesis. Winkelstein was the first person to set up the hypothesis that cigarette smoking could be one of the candidates responsible in the process of cervical carcinogenesis. His hypothesis was prompted by the high correlation in the geographic distribution of cancer of the cervix and the cancer of the lung in the third national cancer survey.52,53 Cigarette associated tumors are predominantly squamous cell tumors like lung or esophagus. It was hypothesized that smoking effect is most manifested by squamous cell oncogenic response. Hence cancer of the cervix could possibly be associated with cigarette smoking. An exhaustive review of the literature, examining the relationship of smoking with cervical neoplasia, revealed positive association between the factor and the disease. Most of the studies reported dose response relationship further supporting the theory.54 It was observed that studies which did not reveal positive association had some bias in the selection of the controls. One of the studies tried to explore the effect of smoking cessation on the lesion size.55 The study revealed that women who had completely stopped smoking showed a reduction in size of lesion by at least 20% revealing a high degree of statistical significance. A recent study from Sweden observed smoking to be an important risk indicator. Most of the variables had lost significance after adjusting the role of human papillomavirus but the odds ratios associated with smoking retained their statistical significance.51

The Indian study conducted by ICMR revealed a high degree of statistical significance with role of smoking for the development of severe dysplasia and malignancy even after adjusting with sociodemographic factors and variables associated with sexual behavior. In this study the comparison was made between ever smoker and non-smoker. There were only 20% of the women who had reported history of smoking as compared to 4% in controls. Role of smoking in husbands was also evaluated for risk of development of cervical cancer. It was observed that an elevated risk of CIN III and was reported for the women whose husbands were smokers. However the risk diminished when adjusted for other confounding factors. As per the results available till date, the tobacco habit including passive smoking could be considered as an important variable for primary prevention.18,19

Dietary factors

Diet has also been under consideration of this important research. Vitamin C and Beta-carotene have been considered as the protective agents against cervical cancer.46 Various studies have been carried out in developed countries on dietary pattern based on diet recall and level of micronutrients in the blood. Study from China had indicated that intake of green vegetables had protective role for cancer cervix.56 A study by Ziegler had expressed a weak relation between the risk of both cervical cancer and in situ disease and intake of carotenoids, vitamin C, folate, fruits and vegetables. Vitamin A was not found to be statistically protective factor.57 Not much information is available from the developing countries including India. There is a need to take up the research on this important aspect for considering this important component of diet for primary prevention strategy.

Viral etiology

The association of cervical neoplasia and the sexual risk factors has inspired the research for a search of venereal agent. The attention was initially focused on Herpes Simplex Virus type II (HSV II). The relationship of HSV II with the risk of cervical cancer was of immense interest in 1960s. The interest in the oncogenic potential of HSV II was reduced when HSV II DNA protein were not detected consistently in tumors. The Indian study at also failed to establish any direct relationship between HSV II and cervical neoplasia.58 The recent investigations focus on possible role of Human Papilloma Virus. Various types of HPV infect the cervix producing flat condyloma (genital warts) or koilocytoic atpia, which resembles mild or moderate dysplasia. Presently around 100 HPV geno types have been identified and one third have been sequenced. HPV types 16 and 18 are considered to be high risk type and HPV 6 and 11 are low risk types. The role of HPV in the process of carcinogenesis is further established by the presence of infections in the cancers of oral cavity esophagus and larynx. The oncogenic potential of the virus is attributed to its E6 and E7 genes. The detailed review has been published else where.59 It has been possible to demonstrate structural HPV antigen in all grades of dysplasia and carcinoma in situ, including invasive carcinoma.

The evidence for causal role of HPV in the development of cervical neoplasia comes from observational and epidemiological studies. The epidemiological data strongly support that HPV infection is primary risk factor, playing a significant role in development of in development of cervical neoplasia. The past or present infection may be an indicator for sexual promiscuity and would act as a surrogate variable. Majority of the studies have revealed that HPV infection of type 16 and 18 is emerging as a primary risk factor for cervical cancer even after adjusting for other confounding factors.60 Recent studies have indicated that high parity becomes a risk factor in the development of CIN III or invasive lesions in the presence of HPV. Among HPV +ve women, dose response relationship were observed for education and age at onset of sexual activity and among HPV _ve women, number of partners and parity were associated with cervical cancer.61 There is a need to generate data on HPV collating it with the other factors in developing countries. Controlling Genital infections is another area, which could lead to prevention of this deadly disease. Studies have generated information on this aspect.62

It is well known that immune system of the body controls the viral infections by neutralizing the virus with antibodies or killing the virus. The recent studies are indicative of important role of immune system in controlling HPV infections. The recent attempt to control HPV induced diseases are targeted to develop preventive immunotherapies and HPV vaccines to prevent infections with high risk genotype.63

Methodological issues

The present exercise attempted to review the work related with the development of cervical neoplasia specifically high-grade lesions (CIN III and invasive cancer). The studies reviewed here had to elicit the information on various sensitive parameters, which might have been a difficult exercise, the quality and the extent of information might be different in the studies leading to the difference in the results. Most of the studies reviewed were of case control approach. The `case control' methodology is most suited for evaluation of risk factors for cancer, as it is a rare disease. The cohort approach might not yield substantial number of cases for the analysis for a defined time period. However some of the studies have adopted nested case control approach from the cohort generated. There is a special advantage of these studies as it includes only incident cases and possibility of recall bias in eliciting of information is minimum.

All the studies under consideration had applied unconditional logistic regression analysis to study the effect of potential confounding variables to elicit the effect of independent risk factors in the process of cervical carcinogenesis. For the very obvious reason classical method of analysis was just not possible because of low sample size in stratum. None of the studies had applied conditional logistic regression since it was difficult to recruit the subjects in matched pairs. It might be quiet difficult to consider matching factors because the disease is of multifactorial etiology. It may also not be possible to study the control for the same investigations. Incomplete information in any of the parameters may render the matched set useless for the analysis. These are some of the issues, which make the matched analysis difficult. Most of the studies had considered age matching (for unconditional logistic regression analysis) although it being an important determinant of the disease, the interest was focused on other risk factors.

Control strategies

Control of cancer of uterine cervix forms a major thrust area of National Cancer Control Programme through secondary prevention approach.64 As discussed earlier, there is severe constraints concerning organized mass scale screening in India, hence the alternatives need to be worked out. It may be mentioned that before the advent of wide scale application of cytology screening in West, before 1960s, much of the mortality from cervical cancer could be brought down through health education of masses, training of professionals and changing the health care seeking behaviour of women.65 These issues are in active focus again in view of the circumstances. There is a definite possibility of carrying out primary prevention approach by modifying life style. Various factors have been discussed which are directly or indirectly associated with the development of cervical cancer. It is possible to modify variables associated with life style through health education, which could help to bring down the incidence of cervical cancer. These include increase in age of marriage through health education and strictly enforcing the legislation. Health education campaign against smoking habits should also target cervical cancer including passive smoking. There is a need to strengthen the Maternal and Child Health Services. This would help in taking care of pelvic infections and nutritional status during anti natal period. It would also encourage deliveries conducted through trained personnel, thus providing better hygiene and facilities. There is also a need to rope in male partners in the programme for health education on sexual promiscuity and smoking. Facilities need to be developed for screening and treating the husbands for any genital infections so as to prevent transmission. Women revealing cervical erosion or cervicitis need to be treated appropriately. Since OC users have been considered at an elevated risk of development of cervical cancer, they should be screened for cervical cancer at regular intervals. Early detection through VIA or cytology could form as an important strategy for early detection of cervical cancer for masses in developing countries. The recent thrust of research on cervical cancer points towards Human Papillomavirus. Thus HPV screening for the high risk group could also be considered for screening. The research on HPV vaccination would definitely get encouraging results and could form an important measure for prevention of this deadly disease. The various studies on this disease have enlightened scientist of different dimensions, but still it is long way to go.

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