The 'Pap' or cervical smear and the role of colposcopy in screening for carcinoma of the cervix.

Cervical cancer is the commonest female genital tract cancer in Singaporean women with an annual age-standardized rate of 17.4 per 100,000. High risk factors are early sexual intercourse, multiple sexual partners and cigarette smoking. Population screening with annual cervical (Pap) smears after beginning sexual activity until age 35 and at 5 year intervals after that can reduce both incidence and mortality rate from invasive cervical cancer. Benign, premalignant and malignant conditions may be identified in smears. The term cervical intra-epithelial neoplasia (CIN) reflects better the continuum of change in precursor lesions and is preferred over the older dual terminology of dysplasia/carcinoma-in-situ for precursors of cervical cancer. Colposcopy is essential for evaluation of all patients with abnormal cervical smears. Colposcopy is used to identify the site, severity and extent of abnormality as well as to aid directed biopsy, plan treatment and allow use of conservative methods to treat the precursor lesions. Colposcopy however, has no role as a primary screening procedure for cervical cancer but instead cervical smears are used for screening.