Geography

The International Agency for Research on Cancer (IARC), part of the World Health Organization (WHO), provides global estimates of the incidence, prevalence and mortality from 27 cancers, in a database known as GLOBOCAN (Ferlay et al 2004).

The GLOBOCAN data indicate that:

• there are nearly 500,000 new cases of cervical cancer every year
  
• worldwide, cervical cancer is the second most common cancer in women between 15 and 44 years of age after breast cancer, and the third most common cause of cancer-related mortality in women, after breast and lung cancer
  
• each year an estimated 270,000 women die from the disease worldwide
  
• cervical cancer is the number one cancer killer in developing countries
  
• unless there is a dramatic improvement in prevention of cervical cancer and the incidence of the disease falls, by 2050, one million new cases of the disease will be diagnosed each year (Ferlay et al 2004).

The prevalence of cervical cancer varies widely around the world. The lowest prevalence is seen in countries such as the UK, Canada, the Netherlands and Finland, where the rates are 9.3, 8.7, 8.6 and 5.5 women per 100,000 per year, respectively (calculated from Ferlay et al 2004). This relatively low prevalence is due to the protective effect of well-established screening programmes, and high levels of compliance with those programmes: 85% of women in the UK, 65-91% in Canada (a figure that varies according to age) and 57% in the Netherlands, are regularly screened (Quinn et al 1999; van Leeuwen et al 2005; SGOC 1998), and organised screening programmes have also had a significant impact on cervical cancer rates in Finland (Anttila et al 1999).

In contrast, cervical cancer is much more prevalent in countries such as Brazil and Thailand, with rates of 18.6 and 15.6 women per 100,000 per year, respectively. This higher prevalence is seen in many countries in which routine screening for cervical abnormalities does not take place (derived from Ferlay et al 2004). Even in well-screened countries, such as the US, there is geographic variation in the incidence of cervical cancer. For example, the incidence is 6.6 cases per 100,000 women in Utah, compared to 12.1 per 100,000 in Los Angeles (SEER Cancer Statistics Review 2005).

These global trends in the prevalence of cervical cancer are reflected in statistics for the incidence of the disease. Again, the incidence of cervical cancer is lowest in countries such as the UK, Canada, the Netherlands and Finland (with age-standardised rates of 8.3, 7.7, 7.3 and 4.3 cases per 100,000 women per year, respectively), which have well-established screening programmes. Incidence is higher in countries such as Brazil and Thailand (with age-standardised rates of 23.4 and 19.8 per 100,000 per year, respectively), in which routine screening for cervical abnormalities does not take place (Ferlay et al 2004).

(Reference: Ferlay et al 2004)

As well as having a higher prevalence and incidence of cervical cancer, mortality rates from the disease are higher in unscreened populations. For example, the age-standardised mortality rates from cervical cancer are 3.1, 2.5, 2.3 and 1.8 deaths per 100,000 women per year in the UK, Canada, the Netherlands and Finland respectively, whilst this rate rises to 10.2 and 8.4 per 100,000 in Brazil and Thailand. In less developed regions, where access to screening programmes can be problematic, cervical cancer remains the leading cause of cancer deaths in women. However, despite the positive impact of screening, even in the developed countries there are still nearly 40,000 deaths per year from cervical cancer (Ferlay et al 2004).

(Reference: Ferlay et al 2004)

While screening has had a significant impact on the prevalence, incidence and mortality of cervical cancer, vaccination against oncogenic HPV types has the potential to further limit the impact of the disease. The addition of vaccination to a well-established screening programme could reduce the lifetime risk of invasive cervical cancer by 46-66%. It could also reduce the incidence of pre-cancerous squamous intraepithelial lesions, thus decreasing the number of women diagnosed with a positive cervical screening result (Goldie et al 2004). Introducing vaccination and triennial cervical screening beginning at age 25 years to countries with no current routine screening could reduce the incidence of cervical cancer by up to 94% (Goldie et al 2004), and a vaccine alone without screening could lead to a 51% reduction in the total number of cases of the disease (Goldie et al 2003).

Pre-cancerous lesions and cervical cancer in Europe

Across Europe as a whole, 60,000 women every year are diagnosed with cervical cancer and 30,000 will die from the disease. Nearly a third of cervical cancer diagnoses in Europe occur in women between the ages of 15 and 45 years (Ferlay et al 2004).

(Reference: Ferlay et al 2004)

The prevalence of cervical cancer varies across Europe. For example, the 1-year prevalence in Slovakia is 21.0 women per 100,000. This figure is similar in Romania (26.8 per 100,000) and Serbia and Montenegro (31.4 per 100,000). In contrast, cervical cancer is less prevalent in Finland (5.5 women per 100,000), the Netherlands (8.6 per 100,000) and Germany (13.2 per 100,000) (derived from Ferlay et al 2004). The differences in prevalence between these countries is largely due to differences in the extent of screening programmes that help to identify and treat cervical abnormalities before the development of invasive cervical cancer (Schiller and Davies 2004; Franco et al 2001).

The age-standardised incidence rate for cervical cancer also varies considerably across Europe with lower rates in Northern and Western regions. The age-standardised incidence rates across Europe in 2002 are (Ferlay et al 2004):

• Eastern Europe: 14.5 cases per 100,000 women per year
  
• Northern Europe: 9.0 cases per 100,000 women per year
  
• Southern Europe: 10.7 cases per 100,000 women per year
  
• Western Europe: 10.0 cases per 100,000 women per year.

The highest rates of cervical cancer are seen in Eastern European countries such as Slovakia (18.5 per 100,000), Romania (23.9 per 100,000) and Serbia and Montenegro (27.3 per 100,000), with the lowest rates in Northern and Western European countries such as Finland (4.3 per 100,000), the Netherlands (7.3 per 100,000) and Germany (10.8 per 100,000), due to the well-established screening programmes in place in these countries (Ferlay et al 2004).

(Reference: Ferlay et al 2004)

Age-standardised mortality rates show a similar pattern, with lower rates in Finland (1.8 deaths per 100,000 women per year), the Netherlands (2.3 per 100,000), and Germany (3.8 per 100,000) where well-established screening programmes are in place, and higher rates in Serbia and Montenegro (10.1 per 100,000), Romania (13.0 per 100,000) and Slovakia (6.1 per 100,000) where cervical screening is less consistent.

As women are more likely to be screened in Western Europe than in Eastern Europe, a correspondingly high number of women will be diagnosed with abnormal cervical cytology. For example, in the UK in 2003-04, over 240,000 women were diagnosed with a positive screening result (UK Government Statistical Services 2004).

Read more about cervical cancer in: Africa, Asia/Pacific, Latin America, North America.