Comparative study of cytologic and colposcopic findings in preclinical cervical cancer.

Seventy-seven patients who had PAP smear cytology and colposcopic examination in a 2-year period between 1988 and 1989 were reviewed. Those with findings indicative or suspicious of malignancy were subjected to biopsy. All 50 patients thus biopsied were confirmed to have preclinical cancer on histological examination. Compared against histology, PAP smear cytology gave an accuracy rate of 90% (5 false negatives) and colposcopy gave an accuracy rate of 94% (3 false negatives). These results demonstrate that the two techniques are useful as screening tests for preclinical cervical cancer. The results are improved if they are used complementarily. However, there was poor specificity in the categorisation of cervical cancer by both methods. This was probably due to the subjectiveness of the two procedures. The study also raised the possibility of a higher incidence of preclinical cervical cancer in the Chinese ethnic group.