Case Report: A steroid-sparing mechanical management of IgG4-related sclerosing cholangitis mimicking cholangiocarcinoma

Background IgG4-SC typically requires long-term corticosteroid therapy. We report a distinctive case of a 65-year-old woman with biopsy-supported IgG4-SC that closely mimicked malignancy. Case summary The patient presented with 10 kg weight loss and CA19–9 of 315 U/mL. She achieved sustained clinical and biochemical remission after repeated endoscopic mechanical decompression alone, with no recurrent obstructive cholestasis during long-term clinical and biochemical follow-up. However, serum IgG4 remained elevated at long-term reassessment, and complete immunologic remission could not be assumed. Conclusion This case raises the possibility of an “obstruction-dominant” presentation of IgG4-SC and suggests that intensive endoscopic biliary decompression may serve as a temporary or, in selected cases, sustained steroid-sparing strategy in carefully selected high-risk patients, without challenging the current role of corticosteroids as standard first-line therapy.