Illustration of invading carcinoma of the pancreas. This composite drawing shows a malignant tumour of the pancreas (lower centre, yellow) plus multi-faceted stones in the gall bladder (green) which may lead to inflammatory pancreatitis (at centre right). The cause of carcinoma of the pan- creas is unknown, and here an invasive tumour has also infected the duodenum (C-shaped tube, pink). The gall bladder and pancreas have a close assoc- iation; their ducts share a common opening to the duodenum. Gall stones lodged in the bile duct (green) are often the cause of acute pancreatitis which has inflamed the pancreas here, and has led to a round cyst forming.