Diagnostic value of liquid-based (Thinprep) preparations in nongynecologic cases

Most studies utilizing the liquid-based ThinPrep method for the preparation of nongynecological specimens report a diagnostic sensitivity and specificity of over 90%. ThinPrep-processed slides in 162 cases sent to us from outside laboratories were assessed for their diagnostic value. These included fine-needle aspiration (FNA) (128) and other nongynecological specimens (34), representing bronchopulmomary washings, body cavity fluids, and urine samples. Slides were examined independently for adequacy and diagnostic value. These results were compared with the final diagnosis rendered upon examination of the entire submitted cytologic specimens, including direct smears, cytospins, and cell blocks. Based on review of the ThinPrep-processed slides alone, diagnosis of malignancy or neoplasia was made in 54 of 86 cases (63%), while 18/86 (21%) were less than optimal and 14/86 (16%) were unsatisfactory. Pulmonary specimens, body cavity fluids, and urine were generally satisfactory, while thyroid and breast FNA were more often less than optimal or unsatisfactory. This limited study suggests that utilization of ThinPrep processing alone may have reduced diagnostic value in the fine-needle aspiration cases studied here.