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.