Abnormal Pap smears with negative follow-up biopsies: improving cytohistologic correlations.

A review of the literature noted 11-16% discrepancy rates in cytology and histology diagnoses. We collected 358 cases with abnormal cytology and matching cervical biopsies. There were 123 (30%) discrepant pairs, of which 34 (27%) had negative biopsies following Papanicolaou (Pap) smears with squamous intraepithelial lesions (SIL). These constituted our study group. All biopsies were obtained within an average of 5 wk after Pap smears (range, 0-18 wk). After confirming original diagnoses, all biopsies were evaluated for the presence of squamocolumnar junction, proper orientation, gross size of specimen, denudation of superficial mucosa, and inadequate sectioning through blocks. Each block was recut at three levels and reviewed microscopically. Five biopsies (14%) needed reorientation. Nine biopsies (26%) showed more than a 2-mm difference from gross size. Eleven (32%) new SILs were found. Adequate deep sectioning and proper orientation of tissues can significantly improve cytohistologic correlations. Copyright 2003 Wiley-Liss, Inc.