Histology of cystic tumors of the pancreas.

The cystic tumors of the pancreas constitute a considerable diagnostic challenge because of their overlapping clinical, radiologic, and pathologic features. They may be difficult to differentiate from one another and from benign lesions such as pseudocysts. Because many of the tumors in this group are potentially curable, correct diagnosis is essential for proper patient management. Even when correctly diagnosed, thorough microscopic evaluation is required for the mucin-producing tumors to correctly determine their degree of malignant progression in any given case. Most recently, molecular analysis of these tumors has demonstrated definitively that the serous and mucinous types of cystic neoplasms of the pancreas are unrelated pathogenetically. Conversely, molecular data indicate similarities between the mucinous types of cystic tumors and ductal adenocarcinoma of the pancreas, but the essential molecular differences that underlie the differences in biological behavior are as yet undetermined.