Cervical cytology: use and follow-up.

The Pat smear was introduced to clinical medicine 35 years ago. It is the most practical means of screening for precancerous lesions of the cervix. Endocervical and ectocervical samples improve detection. Colposcopy and colposcopically directed biopsy will document the most advanced lesion in almost all cases. The need for conization has been greatly reduced. Treatment of intraepithelial neoplasia will prevent the development of invasive cancer of the cervix.