‘Invasive’ Gallbladder Fundus Mass Masquerading as Cancer

Abstract

Background: Gallbladder perforation (GBP) is an uncommon but serious complication of cholecystitis with mortality rates between 12-16%. In 1934, Niemeier described three classifications; chronic perforation with fistula communication, subacute perforation with walled off abscess, and acute perforation into the free peritoneal cavity. Almost 90 years later, GBP remains poorly understood with varying clinical pictures. In this case report of GBP, the overlapping clinical and radiological picture with Gallbadder Cancer (GBC) presented a diagnostic dilemma for radiologists and surgeons. Case: A 77-year-old woman was admitted to The Canberra Hospital, Australia, reporting a 4-month history of weight loss, fatigue, diarrhoea, anorexia, abdominal pain and a firm mass in the right upper quadrant. CT scan demonstrated a mass arising from the gallbladder fundus with invasion into the right sided rectus abdominis and adjacent edge of segment 4b of the liver suggesting malignancy. Surgical resection of the presumed T3 GBC was performed, and surprisingly the histopathology report revealed a gallbladder perforation on a background of acute on chronic cholecystitis, chronic fibrosis at the abscess sites and no evidence malignancy. Conclusion: This rare case illustrates that GBP can have an insidious presentation and with striking clinical and radiological features of malignancy. As gallbladder perforations are uncommon, there is a lack of large studies evaluating clinical and radiological characteristics, especially in the chronic setting. This case exemplifies how complex the evaluation of such patients is for clinicians, and the care needed to confirm diagnosis, especially in an era of evolving neoadjuvant treatment options for GBC.