“…2 In this case, elevated serum CA 19-9 is considered to be caused by cholangitis, as a consequence of primary biliary cholangitis. 3 These findings may lead clinicians to suspect malignancy and to make diagnostic errors. As such, to prevent diagnostic pitfalls, primary biliary cholangitis should be considered as a differential diagnosis for female patients with elevated serum CA 19-9 and lymphadenopathy of unknown origin.…”