Double rarity: malignant masquerade biliary stricture in a situs inversus totalis patient

Background: Situs inversus totalis is a rare anatomical variation of both the thoracic and the abdominal organs. Common bile duct strictures can be caused by malignant and benign diseases as well. 7–18% of the latter ones are 'malignant masquerade’ cases, as pre-operative differentiation is difficult. Case presentation: We present the case of a 68y male patient with known situs inversus totalis and a recent onset of obstructive jaundice caused by a malignant behaving common bile duct stricture. Technically difficult endoscopic retrograde cholangiopancreatography, brush cytology, magnetic resonance cholangiopancreatography, endoscopic ultrasound, and percutaneous transhepatic drainage with stent implantation were performed for proper diagnosis. Cholecystectomy, common bile duct resection with hilar lymphadenectomy, and hepatico-jejunostomy have been performed following multidisciplinary consultation. The final histology report did not confirm any clear malignancy, the patient is doing well. Conclusion: In situs inversus patients, both diagnostic and therapeutic procedures can lead to various difficulties. Benign biliary strictures are frequently misdiagnosed preoperatively as cholangiocellular carcinoma. Surgery is usually unavoidable, involving a significant risk of complications. The co-existence of these two difficult diagnostic and therapeutic features made our case challenging. © 2021, The Author(s).