Application of the Ultrafast Papanicolaou stain to airdried smears in intraoperative diagnosis

Objective: We assessed the usefulness of the Ultrafast Papanicolaou stain (UFP), incorporating air-dried rehydration in intraoperative diagnosis. Study Design: This study involved 482 randomly selected surgical specimens for intraoperative consultation (32 organs from the systemic body: 311 benign and 171 malignant) and 51 cases of peritoneal washing fluid. Specimens were prepared for UFP, frozen sections, Papanicolaou (Pap.), Giemsa, and Alcian-blue stain. Each was diagnosed intraoperatively based on UFP and frozen sections, and postoperatively based on Pap. and permanent histological sections. Results: UFP is simple and fast and produced results within 2 minutes. UFP color differed somewhat from that of Pap. but retained transparency with polychromasia. Nuclear features were clearly observed and nucleoli conspicuous. Lysis of erythrocytes resulted in a clear background. Overall UFP accuracy was 97.3%, frozen section 98.2%, and Pap. 96.1%. Final overall accuracy was 99%. Conclusion: UFP conducted on air-dried smears has many advantages over direct wet fixation and, with adequate sampling for each specimen, is very useful in intraoperative diagnosis.