Routine use of ThinPrep method in fine-needle aspiration material as an adjunct to standard smears

The purpose of this study was to evaluate the efficacy of routine use of ThinPrep® in fine‐needle aspiration (FNA) material as an adjunct to standard smears. We reviewed 50 consecutive, satisfactory‐for‐evaluation FNA materials in which ThinPrep® slides were obtained. In each case, Diff‐Quik‐stained and Papanicolaou‐stained smears were initially prepared, and the ThinPrep® slide was made from the needle/syringe rinse. Smears and ThinPrep® slides were evaluated for the presence of diagnostic material. In addition, the following questions were addressed: could the final diagnosis be made based on smears only, and did the ThinPrep® method add any additional information to the diagnosis? Smears were satisfactory for evaluation in 49/50 cases, and in one case diagnostic material was present on the ThinPrep® slide only. Thirty‐two out of 50 ThinPrep® slides contained material sufficient for evaluation. In 46/50 (92%) cases, final diagnoses could be made based on smears only. In 2 cases, ThinPrep® slides showed additional diagnostic material, and in another 2 cases were critical for the diagnosis. The routine use of ThinPrep® as an adjunct preparatory method to FNA material is not justified, and is associated with an additional, potentially nonreimbursable cost. Diagn. Cytopathol. 2001;25:101–103. © 2001 Wiley‐Liss, Inc.