Diagnostic value, feasibility, and validity of preparing cell blocks from fluid-based gynecologic cytology specimens.

BACKGROUND The current study was conducted to investigate the diagnostic value, feasibility, and validity of preparing cell blocks from fluid-based gynecologic cytology methods. METHODS The authors independently reviewed 125 cell blocks prepared from material remaining after the ThinPrep smear was diagnosed, with a concentration on those cases demonstrating abnormal results. RESULTS The majority of cases were easy to diagnose on hematoxylin and eosin stained sections. The addition of a cell block preparation increased the detection of an endocervical cell component compared with the use of ThinPrep alone. Of the 125 cell blocks studied, 15 were interpreted as high-grade squamous intraepithelial lesions, 70 were interpreted as low-grade SILs, 24 were interpreted as atypical squamous cells of undetermined significance, and 16 were determined to be within normal limits. Eighty-six of the cell blocks (69%) were found to be in agreement with the ThinPrep diagnosis, 29 (23%) demonstrated a lesser degree of abnormality on the cell block compared with the ThinPrep slide, and 10 (8%) demonstrated changes that were more severe than those diagnosed on the corresponding ThinPrep slide. Of the 54 cases for which histopathologic follow-up was available (e.g., punch biopsy, cone biopsy, or hysterectomy), the biopsies, cytologies, and cell blocks were concordant in 15 cases (28%). Biopsy results were found to agree more closely with the cell block preparation than the ThinPrep slide in eight cases, and were found to identify more closely with the ThinPrep slide in four cases. Biopsy showed changes that were less severe than those found on either cytology or cell block in 23 cases (43%). Biopsy demonstrated changes that were more severe than those observed on either cytology or cell block in 4 cases (7%). CONCLUSIONS The results of the current study demonstrate that this technique is feasible and useful as a complement to routine gynecologic cytology slide preparation and examination. Cancer (Cancer Cytopathol) 2002;96:000–000. © 2002 American Cancer Society.