Cervical Cytology - Essay Example

INTRODUCTION      Cervical cancer is one of the most common types of cancer in women world-wide, and is associated with significant mortality rates The most recent statistics in the UK indicate that in 2005 2,800 women were diagnosed with cervical carcinoma, resulting in 950 deaths. In the UK, cervical cancer is the third most common cancer in women under the age of 35 years (Office of National Statistics UK, 2003a).     Approximately 70% of cervical cancers are associated with infection by two oncogenic strains of Human Papilloma Virus (HPV), types 16 and 18 (Schiffman 2005). Other epidemiological risk factors for the development of this disease include sexual activity at an early age, a large number of different sexual partners, cigarette smoking, the use of oral contraceptives and additional socio-economic factors (Office of National Statistics UK, 2003b).  Cervical screening is one of the most effective approaches to detect early cellular pre-cancerous changes in order to prevent the occurrence of cervical carcinoma. The procedure is relatively simple and involves the removal of cells from the surface of the cervix using an instrument called a speculum (Kitchener 2006). This can be performed in several minutes time in a physician’s office. These cells are then spread on a microscope slide, called a smear, which is then analysed by a trained cytologist for the presence of abnormal cells or tissue that may presage the early stage development of cervical carcinoma. When early cellular changes that may be pre-cancerous are detected by cervical screening, there are follow-up procedures that can be implemented to prevent the further progression of tissue abnormalities to cancerous lesions of the cervix (Kitchener 2006). These procedures involve the removal of cervical tissue from the affected area and a detailed histological assessment to ensure that all abnormal tissue is excised to prevent the further development of disease.    Cervical screening techniques were the brain-child of physician Georges Papanicolaou who developed this screening method to detect early stage cervical pre-cancerous lesions. Since then, the “pap smear” as it is called in honor of its discoverer, has been used world-wide for the routine screening of females in an effort to decrease the incidence of this common type of gynecological cancer in women. Despite the availability of this reasonably simple and inexpensive screening test, cervical carcinoma continues to extract a high incidence and mortality rate worldwide (Kitchener 2006). Important areas of current debate regarding the cervical screening policies in the UK involve the question of the age at which screening should commence and the impact of the screening programme and clinical advances in the prevention and detection of cervical carcinoma that require the attention of policymakers, health professionals and women of all ages.    NHSCSP guidelines for cervical screening eligibility    The National Health Service Cervical Screening Programme (NHSCSP) was established in the 1980s to provide eligibility rules and guidelines to encourage cervical cancer screening in the UK (Cervical Screening Programme UK NHS 2006). The guidelines were revised in 2003 to include newer recommendations about appropriate screening intervals and age eligibility requirements to access the free testing service in the UK. Most significantly, the age of initial screening was significantly increased from 20 years to 25 years which has provoked an ongoing controversy regarding the appropriateness of the change in age eligibility for cervical screening. Research data cited by the NHS indicate that cervical screening has a very positive effect in reducing the incidence of cervical carcinoma in women of every age group. These recent statistics published in 2003 show that 3 year screening programmes produced a decreased occurrence in women aged 20-39 by 39%, women aged 40-64 by 69% and women 55-69 years by 73%. These encouraging statistics suggest that routine screening in all age groups could produce further significant reductions in the incidence of this very common gynecological cancer.  Epidemiological evidence suggests that 80% screening rates could be expected to produce a 95% decrease in the incidence of cervical carcinoma. 2006-7 screening rates in UK were estimated at 79%, representing a drop below 1990 statistics which has prompted concern in the medical community. Epidemiological data suggest that cervical screening prevents approximately 4500 deaths per year in the UK with an estimated cost savings of £18,000 per cancer. Screening programme costs and the cost of treating patients with cervical cancer are currently estimated at £157 million per year.    Significance of age restrictions in cervical screening    For millions of women worldwide, the cervical screening tests remain the only available option for the prevention and early detection of cervical carcinoma. Unlike the current policy of the NHS, many advisories world-wide recommend that cervical screening be made available to women beginning at age 20 (Rieck 2005). In contrast, the National Health Service (NHS) cervical screening programme current guidelines afford free cervical screening to women beginning at age 25 with 3 year repeat screening intervals. Women under the age of 25 are currently ineligible for the cervical screening program. In contrast, cervical screening programmes in Wales and Scotland commence eligibility at age 20.  The age eligibility requirement for the initiation of cervical screening tests would appear to be difficult to justify for many reasons. Firstly, as the test is a preventive screening test, it would be advisable to administer the test to ensure the earliest possible detection of pre-cancerous lesions. Recent research indicates that cervical cancer may develop within two years of exposure to oncogenic strains of HPV (Clifford 2003). Given that most women have been sexually active for many years before reaching 25 and the rapidity with which infection may lead to the development of cancerous lesions of the cervix, it would be highly advisable to begin screening in early adolescence, at or before the time an adolescent becomes sexually active. Given current sociological statistics that indicate that the incidence of sexual activity in early adolescence has increased significantly in the past 20 years, early screening may be essential to reduce the incidence of this often-fatal cancer.    Factors contributing to resistance to early-age cervical screening    Advocates of early age cervical screening are often met with resistance by certain religious groups and those who decry what is frequently viewed as a loss of cultural morality reflected in early age sexuality.  These individuals often view the implementation of early age screening for sexually transmitted infections such as HPV- associated cervical cancer as a tacit approval of current cultural mores. This is a difficult challenge for health professionals and other concerned individuals who feel that testing is essential and in no way should be interpreted as a stamp of approval for irresponsible sexual behaviour.  Given that the stated purpose of the NHS cervical screening programme is to reduce the incidence and number of fatalities from cervical carcinoma, the current age eligibility requirements for cervical screening authorization appear unjustifiable. The stated arguments of the NHS for ref  using to authorize cervical screening tests for women under age 25 include the argument that cervical carcinoma in women below age 20 years is uncommon. This argument begs the question of cervical screening. The purpose of the test is to identify abnormal cells of the cervix that may pose a future health problem, and not to identify women who already have the disease. It is entirely possible that apparently healthy women below age 20 may have early cellular changes that, if detected, might prevent the occurrence of cervical cancer later, at about the time when preventive screening is authorised, but too late to prevent the devastating occurrence of advanced disease.    Another justification by the NHS for delayed screening is that the cervical tissue of adolescent women is too variable cytologically to provide conclusive assessment by cervical microscopic screening. This argument is specious, since very few studies have engaged in the analysis of cervical tissue of adolescent women. One of the major reasons for this absence of data is that the programme does not include young women of this age into their screening programme. Their conclusion is mainly speculative rather than data-driven. It is very likely that the inclusion of adolescent women into cervical screening programmes would provide relevant data regarding the differential diagnosis of pre-cancerous lesions and abnormal cell structures in at-risk women as compared to their healthy counterparts. The failure to screen women of this age group represents a loss of a potentially valuable opportunity to assess early stage cellular and tissue changes associated with HPV infection in young women who represent a very high-risk group for the transmission of this sexually-transmitted disease.    The further assertion in the current NHS guidelines that early stage screening is “unnecessary” given the “evidence” that early age pre-cancerous lesions “will still be there” at age 25 when authorised screening begins is untenable and perhaps even ludicrous. How one would obtain such evidence in the absence of early age testing in difficult to understand. If, indeed, early age pre-cancerous lesions were detected, there is no researcher that would ethically permit the patient to wait until age 25 to determine if the pre-cancerous lesion is still around (or more probably, has progressed to a full invasive malignancy).    Research studies relevant to early age cervical screening    The arguments presented by the NHS for increasing the age eligibility requirements for programme screening to 25 years appear indefensible based on current research evidence to the contrary. The current changes to the NHS cervical screening programme that recommend screening to commence at age 25 rather than at age 20 were based on clinical research data that were interpreted to suggest that earlier age  screening was unnecessary. The research study involved a pap smear assessment of almost 3000 women in the Lewisham Borough of London for the occurrence of cervical intraepithelial neoplasia (CIN) in women under age 25 (Bano 2003). The results of this clinical study indicated that 71.5% women displayed normal results. 5.1% showed borderline normal results.  7.4% women had mild cellular abnormalities. Another 2.5% showed serious lesions and 13% could not be analysed. In the high risk group, 34% were tested further and were diagnosed with CIN-2-3 (high grade lesions) and 27% were diagnosed with low grade lesions (CIN-1). !3% were diagnosed as normal. Another 22% refused further testing.  The results of this study may be logically interpreted to indicate that pre-cancerous and potentially cancerous lesions occur in a significant percentage of women under the age of 25. Bano et al (2003) suggested that this study suggests that a failure to screen women under the age of 25 may result in the neglect of an important group of high risk individuals for the development of high–grade precancerous lesions that may progress to invasive cervical carcinoma. The authors strongly recommended the inclusion of 18-24 year old women in cervical screening guidelines.   A different conclusion was reached by an additional research study that used a mathematical modelling system to assess the potential impact of the 2003 NHSCSP guidelines changes on the projected future prevention and incidence rates for cervical carcinoma in the UK (Canfell 2004). The model incorporated factors such as frequency of screening within various age groups in its assessment. A Markov mathematical model was developed in two areas. The first involved HPV infection, CIN progression and the occurrence of cervical cancer. The second area involved screening and treatment of cervical cancer. The study assessed a group of women between the ages of 16-80 years. The model output was a calculated annual age-specific incidence of cervical carcinoma.  The results showed excellent correlation for predicted versus observed incidence rates for women between the ages of 20 and 64 years (Canfell 2004). The data from this study supported the current NHS recommendation change from 20-25 years as the initial screening age based on positive data screening results incorporated into their predictive model (Canfell 2004). Clearly, most observers would agree that current guidelines are very useful and appropriate prevention recommendations, but the theoretical model may not sufficiently address factors important to consider in increasing the recommendation to include women under age 25. As the precise events that result from oncogenic HPV infection and cervical malignancy are not currently understood, there may be insufficient data for the generation of reliable predictive models as they relate to this young age group.  Additional reasons that have been cited to initiate early age screening include the fact the early age recommendations encourage screening in young women as they enter their young adult years, and that there is significant epidemiological data to indicate that adolescent women are engaging in unprotected sexual activity at high rates making this group particularly vulnerable to risk of oncogenic HPV infection and cancer development at a young age (Masicki 2003). Although rarely diagnosed in this age group, early cervical changes may occur during these years that may present as clinical cervical cancer a decade later. For this reason, the younger adolescent group may be a very important cohort that should be routinely screened to monitor cervical abnormalities at early pre-cancerous stages of development (Masicki 2003).    Impact of social and psychological attitudes on cervical screening policy recommendations relevant to age    A research study by involved a questionnaire to assess the attitudes of young women enrolled in university in the UK regarding cervical screening and HPV testing (Philips 2003). The results indicated that 80% of the young women respondents regarded cervical cancer as an important cause of cancer deaths in women. Indeed, the women over-estimated the seriousness of the cervical cancer problem based on current health statistics. The women correctly identified the major risk factors associated with the development of this disease. In regard to the available screening programmes, many women were misinformed about programme recommendations. For example, many believed that the average age at which abnormal lesions generally present in screening results to be considerably older than the facts indicate. Such an erroneous conclusion may serve to cause young women to delay screening under the false impression that young women generally do develop cervical abnormalities. Most importantly, the respondents did not indicate any reluctance to undergo testing based on social issues or concerns. These published findings were meant to reassure policymakers that young women of university age are supportive of cervical screening programme recommendations and might be anticipated to show a high compliance rate if the eligibility requirements for testing included this younger age group (Philips 2003).  Many health professionals have also questioned the issue of informed consent as it relates to psycho-social issues pertinent to cervical screening. Several clinical studies have suggested that women are frequently misinformed about the purposes and limitations of currently available screening tests which they are routinely advised to receive. In the case of cervical screening, there appears to be limited awareness that the screening cannot generally distinguish between early stage abnormalities that may progress to invasive malignancy versus those that may be benign. Despite these misunderstandings of the nature of the test indications, there appears to be little reserve or disinclination among college aged women to undergo cervical screening despite the cultural disrepute associated with sexually transmitted diseases. In younger women the traditional negative associations attributed to the transmission of disease via sexual activity appears far less pronounced and recent studies suggest that young women generally have a positive impression of the introduction of preventive tests and screening methods that decrease the risk of developing serious diseases later in life (Masicki 2003).     New preventive and therapeutic approaches: potential impact on health policy recommendations    The successful development of a preventive vaccine which protects against infection by the most common strains of Human Papilloma Virus (HPV) responsible for cervical carcinoma should prove to be a very important tool in the prevention of this deadly cancer; however, it will not obviate the need for continued cervical screening (Domenighetti 2000). Firstly, the vaccine does not provide protection against all strains of HPV associated with cervical cancer (Schiffman 2005). Secondly, the long-term efficacy of the new vaccines has not yet been established as hey were introduced only recently. In addition, the preventive vaccine is useful only in individuals who have already been exposed to HPV infection. The vaccine is useless in protecting against the development of cervical carcinoma in women with prior exposure to HPV. As HPV is a sexually transmitted viral infection that is widespread throughout the world, it is necessary that young women receive the preventive vaccine prior to the age of beginning sexual activity. Ongoing cervical screening will continue to represent an important adjuvant to the vaccine to assess the long-term utility and effectiveness of this preventive vaccine (Sasieni 2003).    Researchers and healthcare professionals are in general agreement that future health policy recommendations should include HPV screening along with cervical smears as a co-diagnosis of infection with an oncogenic strain of HPV in the presence or absence of cytological changes as these co-administered screening tests may be an important step forward to identify women at significant risk for the development of cervical carcinoma (Conaglen 2001). Many health care providers are of the opinion that policymakers and legislators must be made aware of the newer viral testing methods that may effectively supplement current standard histological tests to increase the accuracy of early stage diagnosis and the prevention of disease progression in high risk individuals (Domenighetti 2000).  These recommendations are especially relevant to young women between the ages of 18-25, who are current ignored by NHS policy recommendations (Sasieni 2003). This group of women has experienced the full impact of changing sexual mores by a culture they have largely inherited along with the increased risks of sexually transmitted disease such as HPV infection. Educational and social policy should focus on responsible personal behaviour, but also provide access to all currently available screening and preventive approaches to sexually transmitted diseases which may have life-threatening consequences that particularly affect the future of this young group.    CONCLUSION    Cervical screening to detect cytological abnormalities that may lead to the development of cervical cancer continues to be an important screening tool responsible for significant decreases in the incidence and mortality rates for cervical carcinoma in decades after its introduction (Kitchenera 2003). The UK NHSCSP has played an important role over the past 20 years in achieving the widespread implementation of this important screening tool in clinical practice. The NHS guidelines are extremely important to patients and clinicians alike as they determine the eligibility criteria for diagnostic screening.   The revisions incorporated in the 2003 NHSCSP guidelines regarding the increased age requirement for screening eligibility represent a step backwards to achieving a national goal of eliminating cervical cancer in the minds of many (Kitchenera 2003). The guidelines revision has had a significant impact on health care practitioners who now must turn away young patients from routine cervical screening despite a plethora of research that suggests that this age group may be a great risk for oncogenic HPV infection and pre-cancerous cytological abnormalities that could be diagnosed early and treated to prevent the possibility of further disease progression (Schiffman 2003).  The revised guidelines especially impact young women who will not reach the age of screening eligibility until age 25. Many of these young women are educated to the risks of oncogenic HPV infection and display positive attitudes about the cervical screening tests that may detect early stage cellular changes before they progress further. This group has been made especially aware of HPV infection due to the current widespread media campaign for HPV vaccination within this targeted age group. Although the introduction of the new HPV vaccine represents an exciting development, it will not replace the need for routine cervical screening within this age group. Moreover, routine cervical screening of vaccinated young women may provide valuable research data on the efficacy of this vaccine in the first generation of recipients.  For all the reasons cited in this essay, the preventive testing for cytological abnormality in young women aged 18-25 is an important component of health policy that should be immediately restored to the NHSCSP health policy guidelines to ensure the best practice prevention of cervical carcinoma.  References Bano, S., Kolhe, D., Zamblera, A., Jolaoso, O., Folayan, L., and Page, J. (2003). Cervical screening in under 25s: a high-risk population. European Journal of Obstetrics & Gynecology and Reproductive Medicine, 139(1), 86-89. Canfell, K., Barnabus, R., Patnick, J., and Beral, V. (2004). The predicted effect of changes in cervical screening practice in the UK: results from a modeling study. British Journal of cancer, 91, 530-536. Clifford, M., Smith, J., Plummer, M., Munoz, N., and Franceschi, S. (2003). Human papillomavirus types in invasive cervical cancer worldwide: a meta-analysis. British Journal of Cancer (2003) 88, 63– 73. Conaglen, H. M., Hughes, R., Conaglen, J. V. and Morgan, J. (2001). A prospective study of the psychological impact on patients of first diagnosis of human papillomavirus. International Journal of STD and AIDS, 12, 651–658.    Domenighetti, G., Grillia, R. and Maggi, J. R. (2000). Does provision of an evidence-based information change public willingness to accept screening tests? Health Expectations, 3, 145–150.  Kitchenera, C., Castleb, P., and Cox, J.  HPV Vaccines and Screening in the Prevention of Cervical Cancer Moscicki, A. (2003). Cervical cytology screening in teens. Curr Womens Health Rep. 3,433–437.  Philips, Z., Johnson, S., Avis, M., and Whynes, D. (2003).  Human papillomavirus and the value of screening: young women’s knowledge of cervical cancer.  Health Education Research, 18 (3), 318-328. 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