**4. Screening for cervical cancers**

grammes are largely opportunistic in nature relying on other channels of health care to

Most female genital tract malignancies have identifiable precursors such as cervical intraepi‐ thelial lesions, vaginal intraepithelial, vulva intraepithelial, atypical endometrial hyperplasia for endometrial cancer while others like ovarian malignancies do not have identifiable precursors making screening modalities non specific. The potential benefits of screening includes early detection of pre invasive cancers and avenue for provision of curative services to patients identified while reassuring those that are negative and rechanneling health resources to other purposes. It must be stated that screening programme have potential limitations of false negative and positive results giving false assurances to affected patients

Irrespective of the type of screening embarked on whether organized or opportunistic, Wilson et al (1968) stipulated certain standards to be met for a successful screening programme and

**•** The condition should be an important health problem, have recognizable latent phase and known natural history with acceptable and available treatment options for identified

**•** The validity and predictiveness of the screening method must be high for the identified

**•** Proposed screening should be a continuous process of case finding and Not "a all in

**•** In addition to the above, policies should aim at designing programmes that will be eco‐ nomically balanced on medicare that will be provided for the diagnosed patients.

Judging from the above stated it is obvious why most of the screening projects designed by most governments in Sub Saharan African and Asia do not succeed as against what is obtained in the developed regions of the world. Gynaecological malignancies like cervical cancer have known life cycle and well established link with 99% of cases of cervical cancer caused by oncogenic strains of human papilloma virus of 16,18, 35 and 41 identified with a duration of 10-20 years of transformation to malignancy noted. The universality and acceptable of the screening methods and treatment options for precursors of the cancer had made it an epitome of success in the area of reducing morbidity and mortality. Ovarian malignancies do not have known precursor thus making screening a challenge without acceptable consensus on

provide a vehicle for screening like the family planning clinics and STI clinics.

and overtreatment of none affected patients. (Kwawukume et al, 2005)

**2. Criteria for a sucessful screeening programme**

these include:

128 Contemporary Gynecologic Practice

patients.

one" project

screening modalities.

precancerous lesion.

The value of screening in identifying precursors of cervical cancers and reducing the cancer burden is well demonstrated in the various methods employed. Ever since the introduction of using cervical exfoliates for screening by George Papanicoloeau and coworkers in 1943, the incidence of cervical cancer related mortalities have reduced by 70% because of well organized screening programmes (Noller 2005,). The relative ease in performing screening of cervical cancer is related to the accessibility of the cervix to allow the analysis of exfoliated cells for cytology, which in turn is a fairly tolerated procedure for patients and relatively cheap to carry out. 60% of cancers of the cervix develop in the unscreened general population but despite screening 40% arise from the screened population. This is attributed to false negative results as result of sampling error or wrong interpretation of cytology reports or improper manage‐ ment abnormal results (Carmicheal, 1984). In addition to the traditional pap smear, other screening methods have being introduced like, liquid based cytology, computer assisted liquid based cytology, colposcopy and Human papilloma virus screening

#### **4.1. Cervical cytology**

This method uses the exfoliated cells, which are examined microscopically, and diagnosis made by recognition of well-known histopathological patterns, which identifies cellular changes of cervical intraepithelial neoplasia. These changes are graded as normal, atypical squamous cells of uncertain significance, low-grade squamous intraepithelial lesions and high grade intraepithelial lesions according to the Betheseda System of classification

The specificity of PAP smear is 98% but the sensitivity is lower and variable because of interobserver differences in interpretation of slides and sampling error

#### **4.2. Preparation for PAP smear**

The procedure of PAP smear is usually scheduled out of menstrual flow periods but should not be deferred because of an unscheduled bleed which may as well errand a cervical pathol‐ ogy.It is advisable for evidence of cervicitis /vaginitis be treated if present and intercourse should be avoided with 24-48hours of the procedure in addition to avoidance of vaginal douching or application of vaginal tampons and creams which may introduce artifacts on the slides examined. Clinical information on the last menstrual period, use of hormonal contra‐ ception, intrauterine contraceptive devices, any form of immunosuppression and previous history of abnormal smears are important to the pathologist in accurate interpretation of smears.
