Prevention of cervical cancer

CANCER of the cervix, or mouth of the womb, is the fourth most common cancer among women worldwide, with over half-million new cases per year. Over 75 per cent of the cases occur in developing countries and in these countries cervical cancer continues to be one of the leading causes of death. Latin America and the Caribbean are amongst these countries that have the highest incidence and mortality rates from cervical cancer worldwide. In this region, age-adjusted incidence rates range from 20 to 80 per 100,000 women per year. Overall, the mortality rates are extremely high in spite of the availability of Pap smear screening. Women from lower socio-economic status, often less educated, are often unaware of cervical cancer screening or have no access to it.

In Jamaica, cervical cancer is the fourth most common cancer overall, and the second most common in women. The incidence here is as much as over twice the rates in some other Caribbean islands with approximately 200 women dying annually as a result of cervical cancer in Jamaica.

Cervical cancer is caused by the sexually transmitted virus Human Papilloma Virus (HPV). There are over 100 types of HPV and once an individual becomes sexually active he or she is exposed to the virus. Although about 80 per cent of sexually active women will acquire the HPV virus in their lifetime, a significant amount of these infections will be transient as the virus is cleared by the normal immune system within the space of about six months to two years. It is those persistent infections that are at risk of developing into cervical cancer. During the pubertal years when the cervical cells are changing in response to increasing female hormones, there is particular increased vulnerability to infection after exposure to the HPV.

Cervical cancer lends itself greatly to the principle of screening as the pathway to developing the cancer can be tracked, for the most part, over about five to 10 years. The changes range from inflammatory changes, atypical changes, to cancer, and can be detected by the Pap smear which is recommended periodically from age 21 years, or three years after initiation of sexual activity. Abnormalities in the Pap smear, if persistent, can be treated by various methods available, and as such, the development of cervical cancer can be averted.

The evidence is that the majority of cases of cervical cancer occur in women who have never done a Pap smear; or those who had done their smears over five years prior to the detection of the cancer. In Jamaica, Pap smears are recommended annually but the evidence is that up to 25 per cent of women have never done one. It is a simple office procedure done by any medical practitioner or nurse in the private office, or the public hospital or health centres, as well as at the Jamaica Cancer Society. It is important to collect the Pap smear results so that abnormalities can be addressed and managed as appropriate.

As there is no specific treatment for HPV, prevention is the key. The use of condoms and avoidance of the predisposing factors of cervical cancer are important. These include smoking, a diet that is not rich in fruits and vegetables, promiscuity, having a promiscuous partner, and early onset of sexual activity. Women with a weakened immune system have a higher than average risk of developing cervical cancer. This includes women who are HIV positive, and women who have had organ transplants and must take drugs to suppress the immune system so that their bodies do not reject the new organ.

The use of the HPV vaccine is a most important factor in the fight towards decreasing cervical cancer. This aims at going a step ahead of detecting early changes on the cervix, by preventing the development of these changes. Importantly, prior exposure to one type of HPV is not a deterrent to receiving the vaccine as one can benefit from coverage from the other types of the virus prevented by the vaccine. Additionally, the production of antibodies from prior exposure has been shown to be less than 50 per cent. The vaccine is recommended from age 12 to 55 years.

For the past two years the government of Jamaica has made the vaccine available to young girls at their entry into high school. The uptake of the vaccine, however, is only about 27 per cent, with most parents being uncertain as to whether they should allow their daughters to take it. Most studies have shown the vaccine to be safe, so parents and students can be reassured of this.

No single approach will be sufficient to decrease the rate of cervical cancer. However, primary prevention by way of vaccination, along with secondary prevention by early detection using the Pap smear, if properly utilised, will go a long way in decreasing the incidence of cervical cancer in Jamaica. An awareness of the predisposing factors of cervical cancer and avoidance thereof clearly cannot be over-emphasised.