Deconstructing the Myths of Cervical Cancer
By Dr. Sylvia C. Robles, photo EM Unit, VLA/SPL/Photo Researchers, Inc.
The doctor had confirmed that she had cancer, that it was on the cervix of the uterus, and that with surgery and possibly radiation therapy, it could be cured completely. But they would need further tests to know the real extent of the tumor.
Despite all the words intended to relieve her anxiety, Flory knew it was certainly cancer-and cancer kills. She could not hold back her tears, and she did not know at this moment whether she wanted to be alone or with someone, whether to shout out her rage or try to wake up from this nightmare.
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She tried to find rational explanations, but there were none -or it was already too late to find them. She did not understand how this could happen to her, at age 45, when she had made sure to get a Pap smear test every year since she had her first daughter at age 19. And the results had always been negative. When the doctor reviewed her previous tests once again, there was nothing-all of them had been negative. Nor could she understand how today, when she had requested an appointment with the doctor in the new clinic, they performed the test and told her:
"You have something there, but I'm going to do the Pap test at any rate."
There was no referral, no new appointment, nothing-but this time when Flory went to get the results-they read "hemorrhagic."
"And what does that mean?" she asked the receptionist, who told her, "I don't know-but I don't think it's bad. Probably nothing-just one of those weird things doctors say."
But wasn't there anyone else she could ask? If not a physician, then a nurse? "No, they are all very busy," she was told firmly. "If you want an appointment, you can have one in two months, but let me warn you, the doctors aren't pleased when people come for nothing."
It was not until almost a year later that she began to notice pain during sexual relations.
Not a great deal-but it had never happened before. After several weeks, she got up the courage to ask the doctors if that meant something.
The news about her having cancer found her at a point in life where she was still working hard to educate her children.
This is a true story and unfortun-ately, it is not unique. It happens to nearly 200 women every day in Latin America and the Caribbean.
This type of cancer is preventable. We now know that is of an infectious etiology, but from a public health perspective we are aware that control programs have not worked as expected. Now we know much more about the natural history of the disease, and scientists are close to making available a vaccine.In 1941, George Papanicolaou described a way of staining the cells that are shed from the epithelium, or outer surface of the cervix, which made it possible to detect the ones with abnormal transformations through a microscope. This technique worked for both the precursor cells, prior to the onset of the cancer, and the fully cancerous cells themselves.
This procedure was based on the knowledge that during the process of carcinogenesis, or the development of cancer, the cells begin to reproduce in a disorderly manner. Therefore, the cell nu-cleus acquires morphological changes that can be identified under the microscope. It was also known that cancerous cells lose their cohesion to the tissue of which they are part and are shed, or sloughed off, more easily. At the time, it was postulated that cervical cancer progressed slowly and that during the development of the tumor, the precursor lesions could be detected, that is, transformations that occur early in the course of the disease. Thus, a timely treatment would impede progress toward invasive cancer. It was on this basis that the screening programs-such as the annual Pap smears-were initiated.
By the end of the 1950s and the early 1960s, when Latin American fertility rates were especially high, many family planning programs were launched. Various methods for preventing pregnancy were offered to women, and since all required a gynecological exam, it was thought appropriate to take advantage of the opportunity to take a sample from the cervix and do a Papanicolaou exam (Pap smear) in order to detect precursor changes or cancer.
Large investments were then made in building cytology laboratories, in the training of personnel at the technical level, and in public awareness campaigns which informed women that they needed an annual Pap smear when they became sexually active.
Even with all this effort, the screening was purely opportunistic. There was not an organized program, requiring strict quality control of each process and a follow-up of the women, so that they were assured treatment-which in many countries was still nonexistent anyway. In contrast, similar strategies gave very good results in the more developed countries, where mortality from cervical cancer declined considerably.
What were the major differences between one experience and the other? How can we learn from the cases where the same intervention process, but in a different social context, gave different results? This was true not only in programs for the screening of cervical cancer, but for many other health problems as well.
These differences in the social contexts and health service organizations were reflected in the levels of education of women, some of whom perceived the test, not as one element of a diagnostic process, but as a preventive measure. In fact, in some places the exam was called "the preventive exam."
Thus, many women thought that once they took the Pap smear exam, that was the end of it. About a third of them did not even go back to seek the results. Furthermore, when the exam results were delivered, the explanations were difficult for them to understand.
Women would be told that they needed another consultation, that it was necessary to do more tests because it was still possible they could have cancer. This created a sort of despair among women, particularly among the poorer ones, for whom additional consultations could be difficult because of time constraints and cost.
The story of Amalia describes what it is like for one of these women when their Pap smear results come in: "When they tell you have something like cancer, you get very nervous& and they explain everything so rapidly that you don't really hear."
"They said: 'Do you have any questions?' and I said, 'No, it's okay, I understood everything clearly,' but I had not understood& and I was so nervous that all I wanted to do was go home."
"When they told me I had cancer, I left crying, walking blocks and blocks, as if someone had died. People stared at me and at my child. I was looking at the trees, as if I never had seen them in my life. I thought that tomorrow I could be dead-and to whom was I going to leave my children? I wanted to ask the physician, but he did not even look at me and only said, 'Please, I need to see the next patient.'"
The most disturbing fact about this situation was that Amalia had what is known as "a high grade lesion," but the results of the Pap test needed to be confirmed through colposcopy and biopsy, before a true diagnosis could be done.
The Pap smear is not a diagnostic test. It is only a screening that separates those who could have lesions in the uterine cervix from those who most likely don't.
Even less known is the fact that this exam does not always yield accurate results. There are women with a positive cytology who end up not having anything-and women with negative cytology who actually have abnormal changes that were not detected.
Unfortunately, this last situation-which is quite serious-is very frequent. It is now known that these cytology tests are capable only of detecting these changes in half of the women who actually have morphological changes in the cells of the cervix of the uterus That is to say, the Pap smear we are using is a very imperfect exam.
This low index of detection is due to multiple factors that can range from the quality of the sample and the quality of the reading to the fact that there was an underlying infection, among others. Even in laboratories with more experience and higher standards of quality control, the results are certain in only about 7 out of every 10 cases.
Perhaps the most important thing to remember is that the cytology or Pap smear is only a sample, and it is possible that when it is taken, the cells with morphological changes are missed. This often occurs because the person taking the sample cannot physically see the cervix well through the speculum, especially in older women.
Another important factor is the high prevalence of sexually transmitted diseases, which cause inflammatory changes that make the sampling and reading of the Pap smear difficult. Several studies have shown that Latin America has a greater proportion of Pap smears flawed by inflammatory changes than do the industrialized countries. Sexual practices in Latin America favor the transmission of the Human Papilloma Virus (HPV), the etiologic, or causal, agent of cervical cancer.
Now that we know more about the disease, we have discovered that it is actually a sexually transmitted disease (STD), caused by the HPV. We also know that at least one out of every four women is infected at least once in her life by this virus, but that not all of these women develop precursory lesions or cancer.
The majority of women who acquire the virus do so before age 30. They tend to present low grade cervical lesions known as mild dysplasias. They eliminate the virus through their own immunological mechanisms, and the lesions cure themselves.
Women who require diagnostic confirmation and treatment are those women with persistent lesions, particularly older women who have high grade lesions or severe dysplasias-as well as any women with changes suggestive of cancer.
This new knowledge has allowed us to make important changes in the design of preventive programs, because Pap smears within family planning programs had basically been targeted at younger women under 30, who are at a much lower risk of cervical cancer, but had ignored older women, who were at far greater risk. Public health programs had been targeting the wrong population group.
This also affected the perception of women regarding screening and health services. They considered that once they had borne all their children-or were no longer sexually active-they did not need further gynecological examinations.
Nor is prevention incorporated as part of their relation to health services. That is to say, older mature women often consult doctors only when they feel ill.
There are new tests that equal or surpass the Papanicolaou (Pap) smear in detecting positive cases of cell abnormalities, or active cancer in the female uterus.
One of these is liquid-based cytology. In this procedure, a sample is taken and is subjected to a procedure that eliminates the mucus and other cells, so that the sample is shown in a slide as a very fine layer of single cells, which permits a much better visualization of the material. There are precise machines for this procedure, but it can also be done manually.
Another method is the visual inspection of the cervix with acetic acid or a 3 percent vinegar solution. This consists of applying acetic acid or vinegar solutions to the cervix, so that any abnormalities can be more easily detected as they turn white. Several studies have demonstrated that this method may have a similar or better detection capacity than the Pap smear.
However, sometimes this procedure also classifies as positive women who do not have lesions and they may need unnecessary additional diagnosis. A variation on this method uses a magnifier to better distinguish which women require additional diagnostic workup.
More recently, it is becoming more practical to identify the Human Papilloma Virus with a sample, or even a test that a woman can administer herself.
The goal of these new series of tests is to establish their margins of safety, their cost-effectiveness, the practicalities of using them in developing countries, and their potential for acceptance with the population.
The Pan American Health Organization (PAHO) is working with several of its member countries in the controlled application of these screening tests, both independently and in combination with other tests. The same screening tests may not be appropriate in all of the situations and contexts, so the countries will hopefully have several options that fit in with their individual social realities and public health capabilities.
However, the screening tests are only a part of a complete program for the prevention of cervical cancer, and it is necessary to assess the most cost-effective treatments as well. In the earlier programs one of the most significant problems was a lack of adequate treatment facilities, which can still be a problem. Access to health services, waiting lists, and the recovery of costs for treatment are also serious problems in Latin America. While the Pap smears may be free in most cases, further diagnosis and treatment may not be. Often patients lack health insurance coverage, or health care centers for the secondary or tertiary levels of treatment are far away, not to mention that the woman must often make multiple visits for further diagnoses, results, and hospitalization.
Previously, the less advanced lesions on the neck of the cervix were surgically removed under general anesthesia. This required at least two days of hospitalization-with the attendant risks of a surgery of this type.
The more advanced lesions, when they were not yet fully invasive cancers, required a hysterectomy to remove the entire uterus-an even more complex procedure.
In the general population, these practices generated a sort of "amputation fear," where the women felt that the surgery removed everything-leaving them "empty and useless."
It is not necessary to treat all of the primary lesions, unless they are persistent, and even for the more advanced cases, there are some new procedures that can be done in an outpatient facility.
Currently the two procedures most utilized are the following:
- The surgical removal of the transformation zone where the lesions are located, using electrical excision, or
- Cryotherapy, which utilizes extreme cold to do an ablation of the affected area.
Both procedures have low degrees of complication. Women are in the clinic for several hours, but do not require total anesthesia, which contributes to a much lower cost than any surgery requiring hospitalization and specialized testing.
Field research for vaccines is on- going. Any vaccine, that is a candidate for a public health program for the control of the Human Papilloma Virus (HPV) would have to fulfill three basic requirements:
- First, the vaccine should be multivalent, that is effective against the most common types of viruses that are associated with cervical cancer. Currently, about 90 different types of HPV have been identified, of which 15 to 20 are associated with cervical cancer. The prevalence of these different types of virus varies considerably, according to the regions and countries.
- The second requirement is that the vaccine should provide prolonged protection, since the opportunity for infection extends for almost 30 years. Ideally, both boys and girls should be vaccinated before initiating any sexual activity, since HPV is a sexually transmitted disease.
- Finally, the vaccine should be appropriate for use in developing countries, ideally with few problems in the "cold chain" that keeps it potent during transport, and practical forms of administration, such as oral or injected.
There are currently two types of prophylactic vaccines:
- one, which is prepared with particles similar to specific strains of the HPV virus, only protects against a few specific types of HPV. This medication is under Phase III study in human subjects and should become available in about five years.
- The other vaccines are composed of recombinant live vectors, some of which are edible. These vaccines have the best chance of meeting the basic requirements, but have not yet begun the necessary clinical trials.
The development of a successful vaccine against HPV represents, without a doubt, the best future prospect for the control of cervical cancer. Nonetheless, several experts caution that an effective, low-cost vaccine that is acceptable to the general population may not be available for up to 10 or 20 years.
In the meantime, to prepare for the elimination phase of this disease, it is necessary to reduce the number of women likely to develop it. Public health programs using screening provide the current best efforts to reduce unnecessary suffering and death.
Development of cervical cancer prevention programs does not occur in a vacuum. They evolve and are reflected in social constructs that influence the success of programs. Recent advances in scien-tific knowledge are forcing a redesign of thepresent strategies of prevention, which are still in the process of change.
This dynamic scenario has important implications for the public perception of this problem and for these programs that directly affect so many women. These new public perceptions need to be included in the development of innovative public health programs that are based on the strategy of community participation.
In an environment where there is an ongoing decentralization of health services, the incorporation of the women themselves into the development of program design strategies-which will intervene in these disease cycles-is critically important for the projected success of these programs. The successful development and availability of an effective vaccine will change the paradigm again; but a door has already been opened that can help address the health problems of women beyond their merely reproductive functions.
Dr. Sylvia C. Robles is coordinator of Non-Communicable Diseases in the Division of Disease Prevention and Control at the Pan American Health Organization.