Cytologic examination of pancreatic juice for differential diagnosis of benign and malignant mucin producing tumors of the pancreas

Background. A new clinical type of pancreatic tumor, the mucin‐producing tumor, has been recognized recently. However, it is not always easy to distinguish benign from malignant tumors preoperatively. In this study, three different methods of differentiating mucin‐producing tumors of the pancreas were compared. Methods. Endoscopic ultrasonography, endoscopic retrograde pancreatography, and cytologic examination of pancreatic juice were performed in 14 patients who had mucin‐producing pancreatic tumors (11 carcinomas and 3 adenomas). Pancreatic juice was collected endoscopically without papillotomy. Results. The sensitivity, specificity, and overall accuracy of endoscopic ultrasonography were 82%, 90%, and 79%, respectively; those of endoscopic retrograde pancreatography were 91%, 91%, and 86%; and those of cytologic examination were 91%, 100%, and 93%. Conclusion. Cytologic examination of pancreatic juice was the best of these three methods for differentiating benign from malignant mucin‐producing pancreatic tumors.