Hilar and Extrahepatic Inflammatory Pseudotumour: A Case Report and Systematic Literature Review

Inflammatory pseudotumor (IPT) is a benign inflammatory lesion that is exceptionally rare in the biliary tree. Its clinical and radiological presentation mimics neoplastic disease, so diagnosis often relies on histology. Surgical resection is the mainstay of treatment. A case of histologically confirmed IPT in a 52-year-old female, successfully managed with surgical resection, is presented. A systematic literature review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify case reports and case series of IPT involving the extrahepatic bile ducts and liver hilum. Searches of PubMed and Embase (from January 1960 to December 2024) yielded 23 original articles that met inclusion criteria. Data on clinical presentation, management, and outcomes were analyzed. A total of 33 cases of hilar and extrahepatic IPT have been reported in the literature. Obstructive jaundice was the most common presentation (79% n=26/32) accompanied by biochemical elevation of liver function tests (91% n=21/23) and bilirubin (77% n=17/22). Surgical resection was the most common treatment (82% n=27/33) with excellent outcomes and only one case of recurrence. However, the follow-up period was relatively short (median of one year). Of five cases initially treated with steroids, three were successfully managed with steroids alone. The other two cases proceeded to surgical resection due to disease progression. Serum immunoglobulin-G4 was high in successfully managed cases and not reported in failed cases. Hilar and extrahepatic IPT is a rare pathology with a similar presentation to neoplastic disease, which can make diagnosis and management challenging. Surgical resection is the mainstay of management, however, in select cases, preoperative biopsy may help avoid unnecessary surgical intervention. Further studies with extended follow-up are needed to optimize diagnostic and therapeutic strategies.