S1543 The Role of Mirizzi Syndrome in Diagnosis of Malignancy

Abstract

Introduction: Mirizzi syndrome is an uncommon presentation of gallstone disease and refers to an obstruction of the common hepatic duct secondary to a stone wedged into the cystic duct. Many cases are not diagnosed prior to cholecystectomy, and the incidence in the developed world is approximately 1-2%.1 Case Description/Methods: An active 70-year-old male with a medical history significant for hypertension, hyperlipidemia, and well-controlled type 2 diabetes presented to his primary care physician for postprandial right upper quadrant (RUQ) abdominal pain and nausea. Outpatient RUQ ultrasound was concerning for choledocholithiasis with common bile duct dilation (8 mm) and cholelithiasis. He was referred to surgery for a cholecystectomy. However, prior to this consult, he presented to the Emergency Department for worsening RUQ pain and jaundice. At this time, he was afebrile and hemodynamically stable. Overall, he was well-appearing with scleral icterus and jaundice. Abdominal exam was non-revealing, with a soft, non-distended, non-tender abdomen and a negative Murphy’s sign. Labs showed no leukocytosis, total bilirubin 10.2, alkaline phosphatase 1450, AST 743, ALT 848, and normal lipase. CT scan showed cholelithiasis, a thickened gallbladder neck suggesting cholecystitis, and high-grade obstruction of the cystic duct and common hepatic duct consistent with Mirizzi syndrome (Figure 1, A-B). Patient underwent EUS and ERCP, which showed an 8.4x11.6mm ill-defined mass in the mid common bile duct (Figure 1, C). Biopsies were obtained and a plastic biliary stent was placed. Total bilirubin trended down while in the hospital, and pathology revealed adenocarcinoma. Discussion: Those with Mirizzi syndrome have a 5.3% to 28% incidence of developing gallbladder cancer.1 Therefore, providers should have a high suspicion for cancer in patients with signs of Mirizzi syndrome, especially in the elderly population. Further testing, including CA 19-9 and more definitive imaging, should be obtained prior to cholecystectomy in those with suspected malignancy, as subsequent surgery is associated with a worse prognosis.1Figure 1.: (A) Axial view shows abnormal enhancement at the cystic duct as it empties into the common hepatic duct. (B) Coronal view shows abrupt luminal transition in the mid common bile duct. (C) EUS shows mass in the mid common bile duct.