Biology 103
2001 First Web Report
On Serendip

The leading cause of cervical cancer is HPV, or the human papilloma virus.HPV is a sexually transmitted disease that infects the cells of the cervix and slowly causes cellular changes (dysplasia) that can result in cancer. These changes can be relatively mild ones that often do not progress, or regress. Larger, deeper lesions (severe dysplasia) are more likely to progress to cancer. Women generally are infected with HPV in their teens, 20s, or 30s, although the disease can take up to 20 years after HPV infection to develop. Cervical cancer can quickly progress to an invasive disease which, where surgery and radiation therapy are unavailable, is always fatal(3).

Cervical cancer prevention efforts worldwide have focused on screening women at risk of the disease using Pap smears and treating precancerous lesions.Precancerous lesions are ones which occur on or in the skin of the cervix, but which are still confined to the skin, without penetrating the surrounding tissues, as found in cancer itself. Where screening quality and coverage have been high, invasive cervical cancer has been reduced by as much as 90 percent (1). Most developing nations, however, have been unable to implement comprehensive Pap smear screening-based programs. In countries where Pap smear screening is available, it often is accessible only to a relatively small proportion of women attending private practices, or, is offered primarily to young women through maternal/child health or family planning clinics where the population that is screened is not generally at high risk. These approaches have had little effect on mortality and are not as cost-effective as centrally organized screening programs implemented by government agencies(3).

Some countries have redesigned their cervical cancer screening programs to be more successful and effective. There have been several strategies that have been developed, including to limit screening to women at highest risk of high-grade dysplasia, to reduce the frequency of screening among women who have had at least one normal smear, and to recommend regular follow-up rather than treatment for young women with mildly abnormal smears. These strategies are important to lower the rate and the intensity of cervical cancer(5).

Several alternative approaches to cervical cancer screening have been proposed and are being researched. These include: visual screening (both magnified and unmagnified visual screening) to identify cervical lesions without reliance on cytology; human papilloma virus tests that may be able to identify women at high risk for cervical cancer, and automated Pap screening machines to identify irregularities in Pap smears that should then be examined by cytologists. These approaches are being evaluated for clinical effectiveness, acceptability to clients and providers, and cost-effectiveness (5).

Increasing the awareness of cervical cancer and also resources available to high-risk women (30 to 50 years of age) will decrease the fatality of cases of cervical cancer.Because cervical cancer generally develops slowly and has a readily detectable and treatable precursor condition (severe dysplasia), it can be prevented through screening and treating women at risk. In many Western nations, invasive cervical cancer incidence and mortality has been reduced by as much as 90 percent through screening programs based on routine cytological examination of Pap smears and treatment of precancerous conditions (4).

It has been argued that cervical cancer screening services are not possible in developing countries because cytology treatment and services are largely unavailable. Many have also assumed that the cost of implementing an effective program would be impossible due to the economically and politically changing state of these nations (2).These arguments are often based on the assumption that successful screening programs must follow a Western model of regular screening of all sexually active women with aggressive follow-up and treatment of women with moderate and even mild dysplasia as well as severe dysplasia. In fact, a large proportion of cervical cancers can be prevented through a much more limited approach. A more limited, feasible, and cost-effective approach would include: targeting older women (age 35 and older); treating only women with severe dysplasia, based on the recognition that most mild dysplasia does not progress to more severe disease; and using relatively inexpensive outpatient treatment techniques to remove cervical lesions . (5).

Alternative approaches to the traditional model that reduce the need for extensive cytology services would make cervical cancer screening and treatment possible in developing countries.Traditional screening programs (based on Pap smears) are almost impossible in developing nations, due to their lack of laboratory facilities, trained personnel and client follow-up, among other factors (2).Aided visual inspection (AVI) could be a cost-effective solution. AVI is the use of a magnifying lens to view cervices treated with acetic acid solution to highlight abnormal tissue, alone or in conjunction with back-up cytology. HPV screening is also an effective method of prevention. Many of the commonly accepted risk factors for cervical cancer, including history of sexually transmitted diseases (STDs) and history of multiple sex partners (or a partner with multiple sexual partners), are probably indicators of HPV infection. Cytology and diagnostic services could be focused on women positive for the HPV types strongly associated with cancer development. Although an inexpensive, accurate HPV test is not yet available, there is continuous research on various tests and HPV screening could become a viable option within the next several years (3). (5).

New screening and treatment methods that are being developed to identify and treat cervical cancer will only be of use to women in developing nations if they are given access to these resources.In order to serve the entire population, developing nations will have to develop new strategies that are possible in their economic state.

WWW Sources

1)Homepage of the American Cancer Society ,

2)Homepage of the National Cervical Cancer Public Education Campaign,

3)Homepage of CAncerBACUP,

4)Homepage of the Centers for Disease Control and Prevention,

5)Homepage of the University of Pennsylvania Cancer Center,

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