الفهرس 
Anatomy of the pancreasOnly 14 pages are availabe for public view
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Abstract
Cystic lesions of the pancreas were first described by Becourt in 1824 (Fernandez-dell; et al., 2010). Until the end of 1970, the spectrum of cystic lesions of the pancreas was relatively narrow and consisted mainly of mucinous and serous neoplasms in addition to pancreatic pseudocyst. from the 1980 onward, the development and widespread use of new imaging techniques led to an increase in the number of resected cystic lesions. This, in turn, advances our knowledge of these tumors. New entities were described, and the pathogenesis, morphology, and biology of the entities already known were studied in more details (Basturk; et al., 2009).
Pancreatic pseudocysts are the most common cystic lesions of the pancreas, accounting for 75% -80% of such lesions (Khanna AK; et al., 2012), and do not present the risk of malignant degeneration (Adsay NV, 2007).
PCN may arise from the ductal epithelium [like SCNs, MCNs, IPMN, and IOPN], endocrine cells, pancreatic acinar cells [acinar cell cystadenoma and cystadenocarcinoma], and mesenchymal elements (Azadeh, 2008). Rarely pancreatic neoplasms that are usually solid may appear cystic (Ji Y; et al., 2006).
The majority of pancreatic cystic lesions is incidental asymptomatic findings, and therefore can present both diagnostic and therapeutic dilemmas (Patwardhan V; et al., 2011). Lesions are often detected when a radiological examination is performed for another reason or when an individual decides to undergo preventive screening investigations (Koen De Jang; et al., 2012).
There is no single test accurate enough to make a sure diagnosis in every pancreatic cystic lesion and so the diagnosis of such lesions is a puzzle (Luca Barresi; et al., 2012).CT is an excellent mean of assessing the pancreatic cystic lesions, however, disadvantages include the use of ionizing radiations particularly when serial examinations are required. Additionally, the internal architecture as fluid content and internal septa are suboptimally evaluated with CT (Jeffrey D & Akram S, 2012). MRI provides the most accurate means of evaluating the internal features of pancreatic cysts (Morgan DE; et al., 1997).
MRCP allows optimal depiction of the internal features of pancreatic cysts, such as septa, cyst contents, and the pancreatic ductal system and its connection (Lucca Barresi; et al., 2012).
Among all methods, EUS, with its high local resolution and whose results of which are not influenced by the presence of gas in the bowel loops, is defined as an examination method essential for the diagnosis of cystic lesions of the pancreas (Okabe Y; et al., 2011). With EUS, it is possible to define cystic localization, size, locularity, internal structural features, mural nodules, contour, cystic wall, pancreatic duct and calcification (Lucca Barresi; et al., 2012).
An advantage of EUS is the possibility to perform fine needle aspiration of cyst fluid. EUS-FNA is considered a safe technique with rare, mostly mild complications (Lee LS, 2012). Cyst fluid can be further studied for cytology, tumor markers, enzymes as well as DNA analysis (Yoon WJ & Brugge WR, 2012).
Complete resection is the only treatment associated with long-term survival in patient 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 the lesions and the risks of preoperative morbidity and mortality (Sharma RR; et al., 2009).
Complete resection includes the resection of the pathologic lesion and appropriate locoregional lymphadenectomy, assessment of the remaining pancreatic parenchyma for residual disease, and reconstruction or drainage of the pancreatic remnant. The range of surgical treatment options include pancreas-conserving resections (enucleation and central pancreatectomy), regional pancreatectomies (pancreaticoduodenectomy and distal pancreatectomy), and total pancreatectomy. The choice of operation is dictated by the location of the lesion, the presence of multifocal PCN, quality life considerations especially with regard to exocrine and endocrine functions and the specific morbidity and mortality of each operation. Most resections can be completed using either traditional open or minimally invasive approaches.