1. INTRODUCTION: CERVICAL CANCER SCREENING

2. Magnitude of the Problem
Third most common cancer in women
Affects 1.4 million women worldwide
Each year, 460,000 new cases occur
Each year, 231,000 women die of the disease
About 80% of new cases are in developing countries

3. Background
99.7% of cervical cancers directly linked to previous infection with human papillomavirus (HPV)
Of more than 50 types of HPV that infect genital tract, 15–20 types linked to cervical cancer
Four of these types are most often detected in cervical cancer
HPV infections often cause no symptoms
Most common signs of infection are small pink or red warts, itching and burning in genital area

4. Background (cont.) After woman becomes infected with HPV:
Infection may remain stable
Infection may regress spontaneously
If cervix infected, may develop into low-grade squamous intraepithelial lesions (LGSILs), also called mild cervical intraepithelial neoplasia (CIN I) or early dysplasia

5. Background (cont.)
For every 1 million women affected, 10% (100,000) will develop precancerous changes in cervical tissue:
These changes are usually in women ages 30–40
About 8% of these women will develop precancer limited to outer layers of cervix (carcinoma in situ) (CIS)
About 1.6% will develop invasive cancer unless CIS detected and treated

6. Background (cont.)
Progression to cervical cancer from high-grade squamous intraepithelial lesions (HGSILs) usually occurs over 10–20 years
Although rare, some precancer lesions become cancerous within a year or two

7. HIV/AIDS, HPV Infection, and Cervical Cancer
39.5 million people living with HIV/AIDS in 2006; almost half women
Heterosexual contact main mode of transmission in new cases
In HIV-infected women:
HPV detected more frequently; resolves more slowly
HPV-associated diseases more difficult to treat
Progression of precancer accelerated

8. HIV/AIDS, HPV Infection, and Cervical Cancer (cont.)
Cervical cancer screening important in this population
Where HIV endemic, 15–20% women positive for precancer
Cervical squamous cell cancer now an “AIDS-defining illness”
Antiretroviral drugs improve quality of life; effect on progression of precancer not known

9. Risk Factors for HPV and Cervical Cancer
Sexual activity before age 20
Multiple sexual partners
Exposure to sexually transmitted infections (STIs)
Mother or sister with cervical cancer
Previous abnormal Pap smear
Smoking
Immunosuppression
HIV/AIDS
Chronic corticosteroid use

10. Age-Related Changes in the T-Zone: Puberty
Columnar cells (red in appearance) are gradually replaced by squamous
cells (pink in appearance). This is a slow process and continues throughout the reproductive years.

11. Preventing Cervical Cancer
Preventing HPV infection will prevent cervical cancer
No conclusive evidence that condoms reduce the risk of HPV infection, although they may provide some protection against HPV-associated diseases

12. Primary Prevention: Development of a Vaccine
A vaccine would be the most effective way to prevent cervical cancer
Vaccine would protect woman against only some types of HPV
Vaccine would need to contain mixture of virus types
At least two vaccines currently being tested

13. Secondary Prevention
Women already infected should be screened to determine whether they have early, easily treatable precancerous lesions
Pap smear is most well-established screening method
Other screening methods:
Visual screening
HPV tests
Automated cytology screening
Pap smear, with its many steps, is problematic in low-resource settings

14. Screening: Visual Inspection with Acetic Acid (VIA)
VIA is at least as effective as Pap smear in detecting disease
VIA has fewer logistic and technical constraints
Studies in South Africa, India and Zimbabwe in 1990s showed VIA as a good alternative to Pap smear
Later studies confirmed that VIA is viable option for screening in low-resource settings

15. Value of VIA in Low-Resource Settings
Can effectively identify most precancerous lesions
Is non-invasive, easy to perform and inexpensive
Can be performed by all levels of health care workers in almost any setting
Provides immediate results that can be used to inform decisions and actions regarding treatment
Requires supplies and equipment that are readily available locally

16. Links to Other Reproductive Health Services
Linking cervical cancer screening and treatment to other services is essential and logical
These services are usually separate, leaving women without access to care and contributing to women’s poor health status
Cervical cancer prevention must be integrated with existing reproductive health care services

17. Links to Other Reproductive Health Services (cont.)
District-based implementation of interventions will ensure that health services are available close to where people live
Nurse or midwife who works in the community is usually the best person to provide community-based, appropriate, safe and cost-effective care