WHO’s cervical cancer screening programmes: managerial guidelines
by Naila Baig Ansari Research Fellow Dept. of Community Health Sciences The Aga Khan University Karachi, Pakistan
Who am I?
Education: MSc (Epidemiology), The Aga Khan University, 2001. Thesis: Care and feeding practices and their association with stunting among young children residing in Karachi-s squatter settlements BBA (Management), The College of William and Mary, Williamsburg, VA, USA, 1989
Research interest: Nutritional and behavioral epidemiology, methodological issues in dietary assessment methods, household food security and gender-related issues, care and feeding practices, management of data and questionnaire designing
Learning Objectives
To understand the importance of establishing a cervical cancer screening programme To be familiar with the WHO recommended managerial factors to consider prior to setting up a screening programme
To understand the concept of “downstaging” in terms of cervical cancer screening
Performance Objectives
Know
the managerial issues to consider when setting up a cervical screening program
the concept of downstaging and possible approaches of downstaging cervical cancer
Understand
Introduction
Cervical cancer is the 2nd most common cancer among women globally Higher cervical cancer mortality in developing countries due to lack of effective screening programs
Introduction
High proportion of women are diagnosed at an advanced stage due to:
– Lack of knowledge among women of the relevance of symptoms – Fatalistic attitude towards cancer and possibility of being cured – Lack of availability of health care in rural areas
– Low priority of women’s health issues
Managerial factors to consider when setting up a screening programme
– Formulation of – Service delivery
screening programmes
– The natural history of
– Information systems – Programme
cervical cancer
– Implications of
evaluation
– Downstaging where
screening policy
cytological screening not possible
Natural History
Cervical cancer develops slowly, and the key precursor is severe dysplasia. The natural history begins with
– the onset of sexual activity at about age 13,
– cervical dysplasia appears about age 18 through 35 years
– Carcinoma in situ begins about age 35 years through to about age 50 when invasive cancers begin to appear as a prelude to death at about age 55.
Risk Factors identified
Human papillomavirus (HPV DNA is present 93% of cervical cancer and its precursor lesions)
– Epidemiologic studies ongoing on cofactors and host
factors that may explain the natural history of HPV infections and their associated lesions.
– Factors under investigation include smoking; use of
hormonal contraceptives; number of live births; young age at first sexual intercourse; use of vitamins such as carotenoids, vitamin C, and folic acid; co-infection with other sexually transmitted diseases (e.g., herpes simplex, HIV, chlamydia); growth factors
Implementation and evaluation of cervical screening
Decision to implement screening for cervical cancer should be based on:
– Evidence that cervical cancer is a major health problem – Characteristics of individuals and populations at risk – An appropriate health service infrastructure
– Technical resources for smear collection and
cytological examination
– Resources for diagnosis and treatment
Which health service sector?
Decision on which health service sector to utilize for screening based on:
Epidemiology
Coverage of women at risk
Use of maternal and child health / family-planning services
Occupational health services
Mobile units of screening
Cost of screening in different health sectors
Frequency of screening
Women with negative cervical smear have low rates of invasive cancer for 5 years. Also rates below those in general population for 10 or more years
Cost-effective approach to recruit high proportion of the population and screen them infrequently rather than low proportion and frequent screening
Estimated reduction in the cumulative incidence of invasive cervical cancer in Chile as a result of a single screen at various ages No. of tests in population (based on 1985 est pop. of Chile) 88,000 81,000 81,000 70,000 57,000 45,000 34,000
Age of single screen
% reduction in cum. incidence 11 15 17 20 26 26 21
30 35 37 40 45 50 60
Cost-effectiveness of two different strategies for cervical cancer screening in Chile
Age Frequency Compliance Reduction in mortality Reduction in treatement costs Cost per case detected
Programme 1 30-55 years 3-yearly 30% 15% US $0.13 million
US $2,522
Programme 2 30-50 years 10-yearly 90% 44% US $0.25 million
US$556
Screening in Primary Health Care
Setting up a screening service
Target group Ensuring target group is screened Recording and reporting Management of women with abnormal smears
What is “downstaging” for cervical cancers
Downstaging is the “detection of the disease in the earlier stage when still curable, by nurses and other non-medical health workers using a simple speculum for visual inspection of the cervix”
Possible approaches to “downstaging” for cervical cancer
Health education Restrict examination to women over 35 years Train female primary health workers to examine the cervix visually and to identify abnormalities
Establish a link between identification of an abnormality and referral
Example of process and impact measures to monitor and evaluate downstaging: Process Measures
– More than 80% of women in the 35-50 year target group are educated on cervical cancer. – More than 80% of primary health workers are educated and trained in visual examination of the cervix.
Impact Measures
– Over 80% of women in the target 35-50 year group are examined at least once.
Example of outcome measures to monitor and evaluate downstaging: Outcome Measures
– Short Term: More than one-third of cervical cancers are discovered by examination – Medium Term: There is more than a third reduction in cases presenting with advanced disease (Stage II and beyond). – Long Term: There is more than a third reduction in the mortality of cervical cancer.
Cancer Control Program
A cancer control program is like a chair with four legs, a seat and a back.
– Four legs represent: interventions or programs of prevention, screening, treatment and palliation.
– Seat joins the four legs into a functional chair. It represents the organizational structure, management and governance of a national cancer control program that integrates its four programs into a functional unity.
– Back of the chair provides support. Represents the infrastructure that needs to be in place for the four programs to function.
Online sources of interest
The Merck Manual of Diagnosis and Therapy, Section 18. Gynecology And Obstetrics Chapter 241. Gynecologic Neoplasms
Cervical Cancer Screening Training Modules
MedlinePlus Health Information on cervical cancer Reproductive Health Outlook (RHO) – cervical cancer