• Home
• GSK in focus
• Cervical cancer: a personal perspective

Cervical cancer: a personal perspective

On International Women’s Day we can celebrate the fact that the outlook for preventing one of the world’s top female cancer killers is better than it has ever been. Cervical cancer kills one woman in the world every two minutes.¹ The good news is that there is now a way to stop cervical cancer before it starts – with vaccination against the challenging virus which causes the cancer, the human papillomavirus.

The global impact of cervical cancer
Worldwide cervical cancer affects over 1.4 million women, is the second most common cancer in women aged 15-45 and the third leading cause of cancer death among women, after breast and lung cancer.¹

Most of the deaths occur in the developing world.  In women who do not undergo regular screening, cervical cancer can be a silent killer as it can take many years to develop and women may not experience symptoms for a long time.² By the time symptoms appear the disease is often in an advanced stage.²

As well as the high death toll associated with cervical cancer, women who survive it –often in the prime of their lives – may be left with the legacy of infertility when radical surgery is needed to remove the cancerous tissue. 

Being diagnosed with cervical cancer was “a living nightmare” for 40-year-old Sabine de Vos who survived this ordeal twice but had to undergo the gruelling experience of three operations, including a hysterectomy, and a three-month course of intensive radiotherapy and chemotherapy to ensure she was totally cancer-free.

“Of course I’m thankful to be alive but the plans my new partner and I had to have another child have had to be abandoned” says Sabine. “I consider myself very lucky that I had my two sons before the disease struck”.

The virus behind cervical cancer
Cervical cancer is caused by a virus called human papillomavirus (HPV) which is caught through sexual activity.³ Unfortunately condoms do not fully protect women from HPV infection since the spread of the virus does not depend on full intercourse only but may also occur simply through skin-to-skin contact in the genital area.^4,5

There are about 100 known types of HPV but only about 15 can cause cervical cancer.⁶ Together four cancer-causing virus types (16, 18, 45 and 31) are the most common, accounting for more than 80 percent of all cervical cancer cases worldwide.⁶

HPV 16, 18 and 45 are particularly concerning since these three are associated with nearly 90 per cent of cases of adenocarcinoma, a particularly aggressive form of cervical cancer.⁷

HPV is very common: it is estimated that up to 80 per cent of women will acquire an HPV infection in their lifetime and up to 50 per cent of these will be with a cancer-causing virus type.^8,9 Luckily most infections resolve spontaneously but when the infection persists the risk of developing cervical cancer rises sharply.¹⁰

A persistent infection with a cancer-causing virus type may cause the development of abnormal and pre-cancerous cervical cell changes which over time can develop into cancer.¹⁰

HPV is a challenging virus because the natural immune response, following infection with a cancer-causing virus type, may not be strong enough to protect against subsequent infection.^11,12,13 What is more, as immune function gets weaker with age, infections are more likely to persist and hence progress to cancer as a woman gets older.¹³

Screening for cervical cancer
The strongest weapon in the fight against cervical cancer is prevention.  Where it is available, regular screening using smear testing provides an early warning system, detecting evidence of abnormal or pre-cancerous cells and allowing in some instances to remove the diseased tissue.  

While screening helps detect abnormalities, around 20 percent of abnormal cases remain undetected.¹⁴ It is also significant that receiving an abnormal smear test result can be a traumatic and unsettling experience for women, as can the surgical procedures used to eliminate the affected cells. 

"Receiving the news of my abnormal pap smear was shocking and scary," says 22-year-old Alexandra "AJ" Stewart who underwent laser surgery to have her abnormal cells removed.  "It was a terrifying experience - I completely shut down and couldn't deal with the possibility of having cancer at my age."

Vaccination against cervical cancer

The good news is that there is now a way to stop cervical cancer before it starts – with vaccination against the human papillomavirus.   It has been estimated that effective vaccination alongside regular screening, could reduce the risk of developing cervical cancer by 94 percent, compared to no intervention.¹⁵

Because HPV is no ordinary virus and poses particular challenges by managing to hide from the natural immune system, it is important to ensure that the immune response induced by vaccination is consistently strong and long-lasting that it protects against the most common and aggressive cancer-causing virus types.  

To stop infections with cancer-causing human papillomavirus types from occurring, vaccination before a first sexual encounter is recommended, but, since a woman can come across the virus at any point in her life, nearly all women could benefit from vaccination.¹⁶

"I’m very pleased that I got the chance to participate in a cervical cancer vaccine clinical trial" says 24-year-old Vanessa Pinto.  "I feel I was given a great opportunity to be involved in bringing this cervical cancer vaccine to women around the world, and I look forward to vaccinating my daughter in the future, so she can be protected from this terrible disease."

Although she may have received the vaccine in the trial, Vanessa – like all sexually active women – has been advised to continue having regular smear tests since rarer HPV types could still cause the disease.  However we now have the means to tackle most of cervical cancer and significantly reduce the alarming statistics associated with the disease.  The essence of International Women's Day is women worldwide choosing to be responsible, independent and in control of their lives.  Today they have the opportunity to safeguard their future by never missing a smear appointment and by talking to their doctor about vaccination – it could save your life.

 

References

1. Ferlay J, Bray P, Pisani P, et al. GLOBOCAN 2002: Cancer incidence, mortality and prevalence worldwide. IARC CancerBase No. 5, version 2.0. IARCPress, Lyon, 2004. Available at: http://www-dep.iarc.fr. Accessed September 20, 2005
2. Canavan TP, Doshi NR. Cervical cancer. Am Fam Physician March 2000; 61(5): 1369-76.
3. Baseman JG, Koutsky LA. The epidemiology of human papillomavirus infections
J Clin Virol 2005; 32 Suppl 1; S16-24
4. Schiffman M, Kjaer SK. Natural history of anogenital human papillomavirus infection and neoplasia. J Natl Cancer Inst Monogr 2003; 31: 14-19
5. Winer RL, Hughes JP, Feng Q et al. Condom use and the risk of genital human papillomavirus infection in young women. N Engl J Med 2006 June 22; 354(25):2645-54.
6. Muñoz N, Bosch FX, de Sanjose S, et al. Epidemiologic classification of human papillomavirus types associated with cervical cancer. N Engl J Med 2003; 348: 518-527
7. Muñoz N, Bosch FX, Castellasague X.  Against which human papillomavirus types shall we vaccinate and screen ? The international perspective.  Int J
Cancer 111; 278-285 (2004)
8. Bosch FX, de Sanjose S. Chapter 1 : Human papillomavirus and cervical cancer – burden and assessment of causality. J Natl Cancer Inst Monogr, 2003; 3-13
9. Brown DR, Shew ML, Qadadri B, Neptune N, Vargas M, Tu W, Juliar BE, Breen TE, Fortenberry JD. A longitudinal study of genital human papillomavirus infection in a cohort of closely followed adolescent women. J Infect Dis 2005; 191: 182-192
10. Kiviat NB, Koutsky LA. Specific human papillomavirus types as the causal agents of most cervical intraepithelial neoplasia: implications for current views and treatment. Journal of the National Cancer Institute 1993; 85(12): 934-5.
11.  Stanley M. Immune responses to human papillomavirus. Vaccine 2006, Vol24S1/16-22
12. Viscidi et al.  Seroactivity to human papillomavirus (HPV) typwes 16,18 or 31 and risk of subsequent HPV infection: results from a population-based study in Costa Rica.  Cancer Epidemiology Biomarkers and Prevention 2004; 13: 324-327
13. Mayrand M, Coutlée F, Hankins C, Lapointe N, Forest P, De Ladurantaye M, et al.  Detection of Human Papillomavirus Type 16 DNA in Consecutive Genital Samples Does Not Always Represent Persistent Infection as Determined by Molecular Variant Analysis. J Clin Microbiol September 2000: 3388–3393
14. Schiller JT, Davies P. Delivering on the promise: HPV vaccines and cervical cancer. Nat Rev Microbiol, 2004; 2: 343-347
15. Goldie SJ, Kohli M, Grima D, Weinstein MC, Wright TC, Bosch FX, Franco E. Projected clinical benefits and cost-effectiveness of a human papillomavirus 16/18 vaccine. J Natl Cancer Inst 2004b; 96: 604-615. 13.
16. Skinner R et al. Presented at EUROGIN 2007

 Back to top