Can cervical cancer be eradicated?

  Cervical cancer places third on the list of the most frequent cancers in women. It follows breast and endometrial (womb) cancers and affects relatively young women with a peak around the age of 40. Mortality linked to this cancer has decreased by more than 50 per cent since pap smear screening was identified in 1941 yet in France, for example, 3,000 cervical cancers are still diagnosed every year and lead to about 1,000 deaths. Here in Thailand, a 2003 study showed that cervical cancer remained the first cancer among women with an estimated 6,000 new cases annually and 2,600 deaths.
Cervical cancer occurs on the cervix, the lower part of the uterus situated at the end of the vagina. Today, its evolution is much better understood and this has had led to significant advances in its prevention and screening. Two main aspects need to be highlighted:
First, the Human Papillomavirus or HPV, which is mainly sexually transmitted, induces the cancer. HPV is very common and is found in more than 50 per cent of women a few years after becoming sexually active. HPV may induce such conditions as genital warts but most of the time does not trigger any symptoms. Out of more than 100 types of HPV, about 30 – the oncogenic or cancer-inducing HPV - can lead to cancer. Interestingly, in about 80 per cent of the cases, the infection is naturally cleared by the body defence’s system within one or two years. Only those with persistent infection are at risk of developing the cancer.
Second, the cancer does not occur overnight and its initial steps can easily be identified during screening. The virus triggers progressive cellular changes called dysplasia, starting with “low grade” lesions that may evolve, in 10 per cent of the cases, to “high grade” or pre-cancerous lesions. Left untreated, about 60 per cent of high-grade dysplasia leads to cervix cancer but this process takes about five to 10 years.
The discovery of the viral root of the disease allowed the development of effective HPV testing in 2000 and the HPV vaccine in 2006. Pap smear findings have also been improved with a more sensitive “liquid phase” method and, combined with HPV testing (HPV DNA), allow physicians to make accurate assessments of the potential evolution of any lesions. These advances have led to new guidelines regarding the prevention and screening of cervical cancer. The guidelines differ slightly from one medical society to another, but can be summed up as follows:
- The Centre for DiseaseControl (CDC) Atlanta, recommends the HPV vaccine for all pre-teens girls (and boys) preferably at age 11 and 12 to allow the build up of immune protection before they become sexually active. Three doses are administered within a six-month period. Women who benefited from the vaccine before their first sexual contact have 70 per cent less risk of getting cervical cancer. This is why, despite effective HPV immunisation, regular screenings must still be carried out.
- Screening for all women should start at 21 with a pap smear every three years until 30 years of age. From 30 through 65, the pap smear is ideally combined with a HPV DNA test every three to five years.
- After 65 years, subsequent screenings depend on past outcomes. Screening may be stopped if the past two combined tests within a five-year interval have been normal.
Unlike many other cancers, which are either too deep within the body or which do not have a simple detection approach, cervical cancer is the most preventable, whether by timely immunisation or early diagnosis of the cellular anomalies. Enhanced awareness in all women and more generous and persuasive prevention campaigns could make this cancer irrelevant in the near future.

Dr Gerard Lalande is managing director of CEO-Health, which provides medical referrals for expatriates and customised |executive medical check-ups in Thailand. He can be contacted |at [email protected].