Endoscopic ultrasound (EUS) allows high resolution imaging of the pancreas. EUS is a very useful technique for evaluating morphological features of a cystic tumors of the pancreas. These features include thick wall type, tumor protruding type, thick septal type, microcystic type, thin septal type and simple type. Malignant cystic lesions may present as a hypoechoic cystic/solid mass or as a complex cyst and are frequently associated with a dilated main pancreatic duct. There is some overlap between EUS appearances of non-neoplastic and neoplastic cystic pancreatic lesions. EUS guided FNA of cystic pancreatic lesions can play an important role in the differential diagnosis of these lesions and deciding about the need for surgery by evaluating cytology and tumor markers such as CEA in cyst fluid. There is some emerging data on EUS guided treatment of cystic pancreatic tumors by injection of alcohol. Endoscopic ultrasound (EUS) allows high resolution imaging of the pancreas. EUS imaging prior to planned endoscopic drainage is useful for appropriate case selection to avoid complications. EUS imaging may change the planned management of up to 37% of pseudocysts prior to attempting endoscopic drainage . With the development of large channel echoendoscopes, real time EUS guided trans-gastric pseudocyst drainage can be performed under EUS control [2, 3]. Beyond the application of EUS for therapy of pseudocysts, EUS has become an important modality for evaluation of cystic pancreatic tumors. This article will focus on the role of EUS for diagnosis and treatment of cystic tumors of the pancreas. Cystic neoplasms of the pancreas can be divided onto serous and mucinous. Serous cystic neoplasms (serous “microcystic” adenomas) are generally benign, and usually there is little or no risk for malignant transformation (very rare serous cystadenocarcinomas have been reported in the literature). Mucinous cystic neoplasms, on the other hand, are either malignant or, if benign, have potential for malignant transformation. Mucinous cystic neoplasms (MCNs) presenting as a cystic lesion in the pancreas include mucinous cyst adenomas or mucinous cyst adenocarcinoma. Another form of mucinous pancreatic neoplasm that may be associated with a cystic lesion is intraductal papillary mucinous neoplasm (IPMN). Ninety percent of mucinous cystic neoplasms occur in the body and tail of the pancreas while IPMNs are common in the head but can also occur in the body and tail. It is clinically important to differentiate pseudocysts from cystic neoplasms as well as serous cystic neoplasms from mucinous cystic neoplasms . All mucinous neoplasms of the pancreas should be considered potentially malignant.
Manoop S Bhutani