Morphometric image analysis of pancreatic disease by ThinPrep liquid-based cytology

Liquid-based cytology preparations are being increasingly used in nongynecologic specimens. The aim of this study is to objectively evaluate pancreatic disease by ThinPrep (TP) liquid-based cytology using morphometric image analysis. In all, 30 patients undergoing preoperative evaluation of pancreatic disease by TP were investigated from January to April 2009. We analyzed cytological features, such as cluster area, cluster circularity, and nucleus area, using morphometric image analysis software and further investigated the cytological findings of TP to determine which are useful for detecting malignancy. Pancreatic cytological findings of TP showed small clusters and loss of cluster irregularity in malignant cells. The patients were diagnostically categorized as inadequate, normal or benign, indeterminate, suspected malignancy, and malignant in 6.6% (2), 46.7% (14), 13.3% (4), 13.3% (4), and 20.0% (6) of the cases, respectively. Morphometric image analysis of 28 patients by TP,excluding two inadequate patients, showed no statistical difference in cluster area or cluster circularity among these cytological categories. In contrast, nucleus area in the normal or benign, indeterminate, suspected malignancy, and malignant categories was 17.6, 57.2, 67.4, and 68.0 μm(2) , respectively, and was associated with diagnostic category (P < 0.05). Pancreatic cytological findings of TP preparations generally show small, round cluster shapes in pancreatic disease; however, nucleus size is a more important criteria for detecting malignancy by TP in pancreatic disease.