The pancreas is an unobtrusive organ, and the prospects and possibilities of solving the physiological and pathological nature of its behavior are numerous. When conducting a pathological study or an investigation of the pancreas, it is important to consider its anatomical and embryological basis as well as the occurrence of age-related frequent lesions. Concerning the latter, both mucous cell hyperplasia and the cystic dilatation of the branch pancreatic duct result in the modification of the tissue surrounding it, i.e. atrophy. Moreover, pathological changes in the pancreas are focal or patchy in nature, especially in non-tumorous lesions, and are related to its neighboring or adjacent organs. Based on the experience and knowledge of its contributors, this publication describes in detail various pathological changes in the behavior of the pancreas. Pathologists, physicians and surgeons who are interested in the pancreas will find it a useful reference source both for their daily work as well as for future research.