Pancreatic cystic tumors.

Cystic tumors of the pancreas are less frequent than other tumors in neoplastic pancreatic pathology, but in recent years the literature has reported an increasing number. After the first report by Becourt in 1830, cystic tumors were classified into 2 different types by Compagno and Oertel in 1978: benign tumors with glycogen-rich cells and mucinous cystic neoplasms with overt and latent malignancy. The WHO classification of exocrine tumors of the pancreas, published in 1996, is based on the histopathological features of the epithelial wall, which are the main factor in differential diagnosis with cystic lesions of the pancreas. Thanks to the knowledge acquired up to now, a surgical procedure is not always required because the therapeutic choice is conditioned by the correct classification of this heterogeneous group of tumors. Clinical signs are not really useful in the clinical work up, most patients have no symptoms and when clinical signs are present, they may help us to pinpoint the organ of origin but never to identify the type of pathology. In the last few years, the great improvement in imaging has enabled us not only to discriminate cystic from solid lesions, but also to identify the features of the lesions and label them preoperatively. More invasive diagnostic procedures such as fine needle aspiration and intracystic fluid tumor marker level are not really useful because they are not sensitive and the cystic wall can show different degrees of dysplasia and de-epithelialization. These are the reasons for sending the entire specimen to pathology. Good cooperation between surgeons, pathologists, radiologists and gastroenterologists is mandatory to increase the chances of making a proper diagnosis. Therefore, we must analyze all the information we have, such as age, sex, clinical history, location of the tumor and radiological features, in order to avoid the mistake of treating a cystic neoplasm as a benign lesion or as a pseudocyst, as described in the literature. Except for inoperable cases due to the critical condition of the patient or non-resectable lesions, surgical treatment differs with the diagnosis. Cystic tumors of the pancreas, therefore, are a heterogeneous group of tumors, with a real problem regarding differential diagnosis between neoplastic and inflammatory lesions. Even with a proper work up, some perplexity may remain about the nature of the lesion and in these cases the surgical procedure has a therapeutic value as well as playing a diagnostic role. The role of surgery is central in the treatment of these tumors because it could be curative when complete resection is possible. In this way, the lack of good therapeutic results with chemotherapy and radiotherapy force the surgeon to go ahead with the procedure. Intraductal papillary mucinous neoplasms represent a new and, from the epidemiological point of view, important chapter in the world of cystic tumors. The margin of resection is important and the surgeon has to be aware that in order to have a curative resection, total pancreatectomy is sometimes required. In the last few years the therapeutic approach has changed thanks to new knowledge of the biological behavior of these tumors. In fact, from a surgical approach in all cases, we are now discussing the possibility of a follow-up not only for asymptomatic serous cystadenomas but also for the little branch side intraductal papillary mucinous neoplasms (IPMNs) in critical patients. A follow-up could be planned even for solid pseudopapillary tumors but it seems risky to leave untreated big tumors in young patients without a certain diagnosis and with so few studies reported in the literature.