Utility of immediate cytologic diagnosis of lung masses using ultrafast Papanicolaou stain

PurposeAt Kagawa University Hospital we conduct immediate cytology using ultrafast Papanicolaou (U-Pap) stain when collecting cytology specimens by bronchoscopy or CT-guided needle aspiration, and report here an investigation of its utility.MethodsThe subjects were 503 patients for whom a final histopathological diagnosis could be made, taken from among 568 immediate cytology patients between July 2000 and June 2008. In immediate cytology at our hospital, a cytotechnologist goes to the bronchoscopy room just before tissue is collected. U-Pap stain is done immediately and examined microscopically. A tentative report is made orally on the spot as to the specimen adequacy, whether it is benign or malignant, and the presumed histopathological type.ResultsOf the 503 patients, the sample was inadequate in only two cases and there were no false positives. With respect to diagnostic accuracy, sensitivity was 82.9%, specificity was 100%, and the correct diagnosis rate was 85.6%. For lesions ≤3 cm, sensitivity was 77.2%, specificity was 100%, and the correct diagnosis rate was 81.3%, and for lesions ≤2 cm sensitivity was 74.7%, specificity was 100%, and the correct diagnosis rate was 81.3%. Diagnostic accuracy was thus maintained even for small lesions. No false positive case was detected.ConclusionBecause immediate cytology enables more precise sample collection, it is thought to be a useful technique that leads to improved diagnostic accuracy, while also improving the technical skill of the doctor collecting samples through immediate feedback.