<prompt> Double duct sign is diagnostic ofPeriampullary carcinomaGallbladder carcinomaKlatskins carcinomaHepatocellular carcinoma  <response>: In pancreatic carcinomaperiampullary carcinoma , the main pancreatic duct may be narrowed or completely obstructed at the site of the tumour, or the distal bile duct may be narrowed. Concurrent narrowing of both ducts results in the so called double duct signReference : page 1134 Bailey and Loves sho practice of surgery 25th edition 