الفهرس 
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Abstract
Cystic lesions of the pancreas were first described in 1824 and can be either inflammatory or proliferative in nature. Pseudocysts make up the majority of all cystic lesions of the pancreas, the remainder comprising cystic tumors and true cysts (true cysts accounting for a very small percentage of these lesions).
PCN may arise from the ductal epithelium SCNs, MCN, IPMN, ITON, endocrine cells, pancreatic acinar cells (acinar cell cystadenoma, acinar cell cystadenocarcinoma), and mesenchymal elements. SPT also appear cystic on imaging studies, but in this group of tumors the cystic change is degenerative in etiology. The originating cell lineage of these tumors is as yet uncharacterized. Rarely, pancreatic neoplasms that are usually solid may appear cystic.
The majority of cystic tumors of the pancreas are slow-growing and asymptomatic. When symptoms occur, they are usually secondary to a mass effect and tend to be vague and poorly localised in nature. Only intraductal papillary mucinous tumours (IPMTs) present with pain and may mimic chronic pancreatitis.
An accurate diagnosis of a pancreatic cystic lesion is often difficult because traditional cross-sectional imaging tests cannot provide diagnostic images. Endoscopic ultrasound (EUS) has several features that may make it an excellent tool for the imaging of pancreatic cysts. As the pancreas lies directly adjacent to the stomach, an EUS transducer can be placed in close proximity to the pancreas, and the entire gland can be readily imaged. Ultrasound imaging is well suited for assessment of cystic lesions. Endoscopic ultrasound (EUS) can provide detailed images of the wall and septations and adjacent masses that characterize many different types of cysts. Endoscopic ultrasound (EUS)-guided FNA of solid pancreatic masses has been successful in improving the diagnostic accuracy of EUS imaging alone.
Fine needle aspiration (FNA) is often used to improve the results of pancreatic imaging. However, CT-guided FNA has been relatively unsuccessful in the diagnostic evaluation of cystic lesions because of the small size and inaccessibility of pancreatic cysts. Markers such as CEA should be absent in the fluid secreted by serous cystadenomas. The ability to distinguish between serous and mucinous cystic lesions using fluid analysis has been demonstrated previously using cyst fluid obtained during surgery or through CT-guided aspiration. EUS-FNA-derived cystic CEA levels have been shown previously to be the most accurate (79%) means of diagnosing mucinous cystic lesions of the pancreas. The cystic fluid CEA level (normal value <2.5ng/mL) remains the most widely used molecular diagnostic test in the preoperative evaluation of pancreatic cystic neoplasm (PCN). Elevated CEA levels (>192 ng/mL) have been associated with MCN and cysts with a low CEA (<5 ng/mL) are more likely to represent SCNs. Overlapping CEA values between cyst types makes interpretation difficult without the aid of additional clinical information. Analysis of CA19-9 (normal value >37u/L) and other cyst fluid markers remains equivocal, with conflicting data regarding the possible utility of such tests.
Few nonsurgical treatment alternatives exist. Although the short-term results following experimental alcohol ablation of unilocular pancreatic cysts appear promising. Complete resection is the only treatment associated with long-term survival in patients with malignant PCN. Surgical removal of premalignant cystic tumors reduces the risk of dying from the eventual development of an invasive pancreatic cancer .Prophylactic resections remain challenging to both the surgeon and the patient because of the uncertain biological behavior of these lesions and the risks of perioperative morbidity and mortality.