Evaluation and Management of Pancreatic Cystic Lesions
Journal of Clinical Outcomes Management. 2015 December;22(12)
References
). The cyst was surrounded by a thick rind of enhancing tissue and had occluded the splenic and superior mesenteric veins, and was encasing the splenic artery. The main pancreatic duct was dilated at 7 mm with pancreatic body and tail atrophy. There was no evidence of metastatic disease or pathological lymph nodes. An EUS was performed and showed a large complex cyst with thick walls of up to 2 cm. Fine-needle aspiration (FNA) yielded a carcinoembryonic antigen (CEA) value of 2.3 ng/mL and cytology showed “bland epithelial cells.”
Despite the reassuring CEA and cytology results, a high concern for a malignant cystic lesion remained based on cyst size, main pancreatic duct dilation, and atrophy noted in the distal pancreas. The patient underwent surgical resection including subtotal pancreatectomy, splenectomy, subtotal gastrectomy, and superior mesenteric and portal vein resection with reconstruction. Pathology revealed the cyst to be a benign pseudocyst.
This case reflects some of the critical challenges in current management of pancreatic cysts. By history, this patient had no suspicion for pancreatitis, making a pseudocyst less likely in a differential diagnosis. When the patient presented 7 years later, again with no reported history of pancreatitis, there was clinical concern for a branch duct IPMN. Although the cyst fluid CEA and cytology were reassuring, the patient met surgical criteria by the 2006 international consensus criteria and the more recent AGA guidelines. Interestingly, the narrowed 2012 international consensus guidelines for surgical resection would have recommended observation. This case highlights the need for better diagnostic tests.
• What is the epidemiology of pancreatic fluid collections and how do they present?
Pancreatic fluid collections are not true cysts as they lack an epithelial cell lining. They often occur in the context of either acute or chronic pancreatitis, and are considered benign or nonmucinous cysts [7,8]. Duct disruption occurs causing pancreatic fluid accumulation, initially defined as an acute peri-pancreatic fluid collection, or an acute necrotic collection if necrosis is present. Over about 4 weeks a more defined cyst wall forms and the cyst is now classified as either a pseudocyst or walled-off pancreatic necrosis [23]. In one review, the median age at presentation was 49 with a male:female ratio of 2:1. Only 52% of fluid collections were discovered following an acute attack of pancreatitis [24]. The risk factors for pancreatic fluid collections are similar to the risk factors for pancreatitis, with the most common being alcohol use and gallstones [24]. Potential symptoms include abdominal pain, weight loss, gastrointestinal bleeding from pseudoaneurysms, obstructive symptoms, sepsis from super infection, and obstructive jaundice [8,24,25,26,27].
• How are pancreatic fluid collections diagnosed and managed?
Clinical suspicion for pancreatic fluid collections should increase if a cyst is diagnosed in the context of acute or chronic pancreatitis [28]. However, other types of cysts can cause ductal obstruction and pancreatitis, so further investigation may be needed, including review of prior imaging if available. The presence of internal debris, the presence of imaging findings of acute or chronic pancreatitis, and fluid extension beyond the pancreas and taking the shape of the retroperitoneum are often characteristics found in pancreatic fluid collections [29,28,30]. If needed, FNA with assay of amylase may be helpful. An amylase value of 5680 IU/L or greater was 84% sensitive and 64% specific (AUC 0.69) for pseudocysts in one study [31].
