Additional slides from residual ThinPrep Pap tests: Of potential diagnostic benefit in equivocal cases?

The aim of this study was to further evaluate the diagnostic significance of additional slides prepared from residual ThinPrep (TP) Pap Tests. Up to 10 repeat slides were prepared from 105 residual TP cervical samples. All additional slides were evaluated for the presence of diagnostic elements which were not found on the primary TP slide. After the evaluation of the repeat slides, an upgraded diagnosis was noted in 15 cases (14.3%). The reclassified cases included: three negative cases reclassified as two ASC-US and as one LSIL, seven cases of ASC-US reclassified as six LSIL and as one HSIL, and five cases of LSIL reclassified as HSIL. The highest rate (7/15 cases, 46.7%) of cases with an upgraded diagnosis was noted in the ASC-US diagnostic category. Our results suggest that repeat processing of residual TP cervical samples may represent an adjunctive diagnostic tool for a more accurate classification of ASC-US cases. Nevertheless, the practical value of this approach seems to be limited by its significant cost and its uncertain effectiveness.