Cervical cancer, which is almost always preventable, continues to be a
large public health problem in many developing countries because of
limited access to screening and treatment. Each year there are about
400,000 new cases of cervical cancer—80% of which occur in women living
in developing countries1,2.
The vast majority (99.7%) are associated with infection with one or more
oncogenic types of human papillomavirus (HPV), which is sexually
transmitted.3 Although women
generally are infected with HPV in their teens, 20s or 30s, invasive
cancer may not develop for as long as 10 or 20 years after infection.
Since 1989, the JHPIEGO Corporation, an affiliate of the John Hopkins
University, has been exploring the feasibility of several low-cost
alternatives for cervical cancer detection. Prominent among these is
unmagnified (naked eye) visual inspection using a dilute solution of
acetic acid (VIA). In March 1999, researchers from JHPIEGO and the
University of Zimbabwe reported in The Lancet that the sensitivity
(77%) and specificity (64%) of VIA is comparable to good quality Pap
smears.4 This large-scale study,
which involved more than 10,000 women attending primary healthcare clinics
in Zimbabwe, confirmed the findings of similar but smaller studies in
South Africa and India. A second major finding from the Zimbabwe study was
that nurse-midwives, who did all the VIA tests, quickly learned to
competently perform VIA.5 This is
important because the vast majority of developing country women who need
to be tested live in areas where there are no doctors and where Pap smears
may never be available. Furthermore, unlike Pap smears that require
several days to a week to get the results back, with VIA the results are
available immediately. As a consequence, these nurse-midwives were able to
quickly and easily identify women with no disease, those with abnormal
findings suitable for immediate treatment, and those requiring referral
for very large lesions or advanced disease.
With the establishment of VIA as an acceptable alternative to Pap
smears,6 it is now possible to
combine VIA with outpatient treatment of precancerous lesions at the same
visit. For example, cryotherapy, which involves freezing the cervix with a
liquid coolant such as carbon dioxide to destroy the abnormal cervical
tissue, is effective and has been used extensively throughout the world
for more than 20 years.7,8,9
Cryotherapy also is one of the easiest methods to learn and can be
performed by nurses and other healthcare workers.
In light of these promising epidemiologic studies and the availability
of a simple, low-cost outpatient method of treatment, the opportunity to
markedly reduce the incidence of cervical cancer globally is at hand. As
the first step (Phase 1) in this process, JHPIEGO will conduct safety,
acceptability, feasibility and program effectiveness (SAFE) Demonstration
Projects in separate regions of the world during the next 2 years.
(Currently, projects are just starting in Thailand and Peru with a third
project to be initiated in Africa within the next 6 months.) These service
delivery demonstrations projects are needed to:
-
show that nurses and midwives can safely and
competently perform both VIA and cryotherapy under field
conditions,
-
demonstrate that they can confidently recommend
and treat (or refer) women with abnormal (precancerous) lesions, and
-
document the acceptability and feasibility of
cervical cancer testing that is directly linked to immediate
treatment.
In countries where SAFE Demonstration Projects will be implemented,
advocacy and community preparedness activities also will be performed to:
-
assess the readiness of a country to launch a
large-scale cervical cancer prevention program, including
identification of key mechanisms for implementing it into a
country’s healthcare delivery structure,
-
develop interventions for increasing knowledge
and awareness at the national and community level that cervical cancer
can be prevented, and
-
identify and implement mechanisms for
mobilizing and empowering women’s groups and other local
organizations to actively support and embrace a national cervical
cancer program.
By 2001, we anticipate that the results will confirm that well-trained
healthcare workers can quickly and easily identify women who are suited
for immediate treatment with cryotherapy or refer those requiring more
aggressive treatment for advanced disease. We also expect to learn that a
test, treat or referral program is a safe, acceptable and feasible
approach for preventing cervical cancer in low-resource settings. Finally
we anticipate identifying ways in which large-scale cervical cancer
prevention programs can be implemented nationally through a combination of
individual and community education, local NGO and women’s groups
participation, and sponsorship by indigenous service organizations and
clubs.
In summary, this approach to managing precancerous cervical
lesions has the potential to reduce disease progression and death in a
majority of the most vulnerable women who currently do not have access to
Pap smears and physician-staffed services. Also, it has the potential to
reduce referrals of women with early lesions to higher levels of the
healthcare system as well as increasing the chance of detecting invasive
cancer at an earlier stage when it can be treated successfully. Finally,
once a precancerous lesion is treated with cryotherapy, a woman’s risk
of developing an infection with other HPV types may be reduced for several
years while those women found to be normal may not need retesting for five
or more years.10
JHPIEGO is founding member of the Alliance
for Cervical Cancer Prevention. The CECAP Program is supported through
a grant from the Bill and Melinda Gates Foundation and by Johns Hopkins
University.
References
-
Pisani P. 1998. International Agency for
Research on Cancer. Personal communication.
-
Sherris J. (ed). 1998. Preventing cervical
cancer in low-resource settings. Outlook 16(1):1-8.
-
Walboomers JMM et al. Human papilloma
virus is a necessary cause of invasive cervical cancer worldwide. J
Pathol (in press).
-
University of Zimbabwe/JHPIEGO Cervical
Cancer Project. 1999. Visual inspection with acetic acid for cervical
cancer screening: test qualities in a primary-care setting. Lancet
353: 869-873.
-
In the Zimbabwe study, nurse-midwives
learned to perform VIA during a week-long competency-based training
course. The training involved use of a specially designed VIA cervical
atlas and repeated practice performing the procedure on pelvic models
prior to working with patients.
-
Kitchener HC and P Symonds. 1999.
Detection of cervical intraepithelial neoplasia in developing
countries. Lancet 353: 856-857.
-
Mitchell MF et al. 1998. A randomized
clinical trial of cryotherapy, laser vaporization, and loop
electrosurgical excision for treatment of squamous intraepithelial
lesions of the cervix. Obstet and Gynecol 92: 737-44.
-
Olatunbosum OA et al. 1997. Outcome of
cryosurgery for cervical intra-epithelial neoplasia in a developing
country. Int J Gynecol Obstet 38: 305–310.
-
Cox JT.1999. Management of cervical
intraepithelial neoplasia The Lancet 353: 857-859.
-
Lonky NM et al. 1997.Selecting treatment
for cervical disease. OBG Management (Part 2, January issue):
63-70.
