A 68-year-old man comes to the office for follow-up of an abnormal finding on abdominal CT scan. Two weeks ago, the patient was seen in the emergency department for left lower quadrant abdominal pain. CT scan revealed acute sigmoid diverticulitis, which improved with oral antibiotics, as well as a cyst in the head of the pancreas. The patient has no history of pancreatic diseases and reports no epigastric pain, diarrhea, or weight loss. He used to drink alcohol heavily but stopped several years ago and does not smoke cigarettes. Family history is unremarkable. Vital signs are within normal limits. Physical examination shows no abnormalities. MRI of the abdomen confirms a 4.6-cm, multilocular cyst in the head of the pancreas with thickened walls. The main pancreatic duct is mildly dilated. Serum amylase, lipase, and liver chemistry studies are within normal limits. Which of the following is the next best step in management of this patient?

Question

A 68-year-old man comes to the office for follow-up of an abnormal finding on abdominal CT scan.  Two weeks ago, the patient was seen in the emergency department for left lower quadrant abdominal pain.  CT scan revealed acute sigmoid diverticulitis, which improved with oral antibiotics, as well as a cyst in the head of the pancreas.  The patient has no history of pancreatic diseases and reports no epigastric pain, diarrhea, or weight loss.  He used to drink alcohol heavily but stopped several years ago and does not smoke cigarettes.  Family history is unremarkable.  Vital signs are within normal limits.  Physical examination shows no abnormalities.  MRI of the abdomen confirms a 4.6-cm, multilocular cyst in the head of the pancreas with thickened walls.  The main pancreatic duct is mildly dilated.  Serum amylase, lipase, and liver chemistry studies are within normal limits.  Which of the following is the next best step in management of this patient?

Quizplus · Accepted Answer

Explanation: Pancreatic cysts are common incidental findings in the aging population, with an estimated incidence of 40% in individuals age >70. The risk of malignancy in any given cyst is quite low (~0.01%), and many can be managed conservatively with surveillance imaging. However, some pancreatic cysts carry a risk for malignant transformation. Because cyst resection has significant risks of morbidity and mortality, the goal of management is to identify lesions that are at high risk for malignancy. Several radiographic features are associated with higher risk for malignancy, including: Large size (≥3 cm) Solid components or calcifications Main pancreatic duct involvement (ie, ductal dilation) Thickened or irregular cyst wall This patient's pancreatic cyst has several high-risk features (ie, large size, main ductal dilation, thickened walls) and requires further evaluation to rule out malignancy. Endoscopic ultrasound (EUS)-guided biopsy is a minimally invasive approach to tissue sampling; however, surgical resection (without prior biopsy) may be considered for very high-risk lesions. (Choices B and E) Unlike true pancreatic cysts, an uncomplicated pancreatic pseudocyst (eg, rounded, well-circumscribed fluid collection formed by pancreatic necrosis in pancreatitis) has a very low risk of malignancy and usually does not require further intervention. However, symptomatic (eg, abdominal pain) or rapidly enlarging pseudocysts may require endoscopic drainage. This patient has a true cyst with high-risk features concerning for malignancy and requires further evaluation with an EUS-guided biopsy. (Choice C) Screening for intracranial aneurysms is recommended for patients with autosomal dominant polycystic kidney disease (ADPKD). Although ADPKD can be associated with pancreatic cysts, it typically presents with hematuria, flank pain, hypertension, and chronic kidney disease earlier in life. Additionally, numerous renal cysts would likely be visible on CT scan. (Choice D) Serologic testing can help diagnose amebiasis due to Entamoeba histolytica. Although amebiasis can cause abdominal pain, it presents with diarrhea (bloody or nonbloody), fevers, weight loss, and liver abscesses (not pancreatic cysts). Educational objective: Most pancreatic cysts are benign and can be managed conservatively (eg, surveillance imaging); however, some carry a risk for malignant transformation. Cysts with high-risk features (large size, solid components or calcifications, main pancreatic duct involvement, thickened or irregular cyst wall) require further evaluation with endoscopic ultrasound-guided biopsy and possibly surgical resection. References: ACG clinical guideline: diagnosis and management of pancreatic cysts. (http://www.ncbi.nlm.nih.gov/pubmed/29485131) Revisions of international consensus Fukuoka guidelines for the management of IPMN of the pancreas. (http://www.ncbi.nlm.nih.gov/pubmed/28735806)

A 68-Year-Old Man Comes to the Office for Follow-Up of an Abnormal