Microcolposcopy in the diagnostic evaluation of abnormal cervical cytology: when and why to do it.

Microcolposcopy is an in vivo cytological examination of the uterine cervix allowing the localization of exoendocervical precancerous lesions. The aim of this study was to assess the diagnostic reliability of microcolposcopy by means of correlation with histology, colposcopy and Pap test results. For the study, 256 patients with abnormal Pap test results were selected and subjected to colposcopy and microcolposcopy with the aim of evaluating the presence of any intraepithelial lesions. One hundred and nine of these patients were subjected to a biopsy. Colposcopy, histology and cytology results were compared with those obtained by microcolposcopy. In low-grade squamous intraepithelial lesion (LSIL) cytology cases, the percentage agreement on lesion grade between Pap test and microcolposcopy results was 74%, while in high-grade squamous intraepithelial lesion (HSIL) cytology cases, it was equal to 80%. The comparison between colposcopy and microcolposcopy showed a level of agreement of 72% for lower grades and 68% for higher grades. Finally, histology was in agreement with microcolposcopy in 73% of cervical intraepithelial grade 1 neoplasia (CIN 1) cases and reached 71% for CIN 2-3. Microcolposcopy proved to be accurate with regard to the diagnosis of lesion grade, and showed to be definitive in patients where cytology was positive for HPV infection and colposcopy was not able to identify any lesions.