Jaundice accompanied by a painlessly swollen gallbladder (known as Courvoisiers sign) may also raise suspicion, and can help differentiate pancreatic cancer from gallstones.Medical imaging techniques, such as computed tomography (CT scan) and endoscopic ultrasound (EUS) are used both to confirm the diagnosis and to help decide whether the tumor can be surgically removed (its "resectability"). On contrast CT scan, pancreatic cancer typically shows a gradually increasing radiocontrast uptake, rather than a fast washout as seen in a normal pancreas or a delayed washout as seen in chronic pancreatitis. Magnetic resonance imaging and positron emission tomography may also be used, and magnetic resonance cholangiopancreatography may be useful in some cases. Abdominal ultrasound is less sensitive and will miss small tumors, but can identify cancers that have spread to the liver and build-up of fluid in the peritoneal cavity (ascites). It may be used for a quick and cheap first examination before other techniques. A biopsy by fine needle aspiration, often guided by endoscopic ultrasound, may be used where there is uncertainty over the diagnosis, but a histologic diagnosis is not usually required for removal of the tumor by surgery to go ahead.Liver function tests can show a combination of results indicative of bile duct obstruction (raised conjugated bilirubin, γ-glutamyl transpeptidase and alkaline phosphatase levels). CA19-9 (carbohydrate antigen 19.9) is a tumor marker that is frequently elevated in pancreatic cancer. However, it lacks sensitivity and specificity, not least because 5% of people lack the Lewis (a) antigen and cannot produce CA19-9.
Exceptions to this are the functioning PanNETs, where over-production of various active hormones can give rise to symptoms (which depend on the type of hormone).Bearing in mind that the disease is rarely diagnosed before the age of 40, common symptoms of pancreatic adenocarcinoma occurring before diagnosis include:

Pain in the upper abdomen or back, often spreading from around the stomach to the back. The location of the pain can indicate the part of the pancreas where a tumor is located. The pain may be worse at night and may increase over time to become severe and unremitting. It may be slightly relieved by bending forward. In the UK, about half of new cases of pancreatic cancer are diagnosed following a visit to a hospital emergency department for pain or jaundice. In up to two-thirds of people, abdominal pain is the main symptom, for 46% of the total accompanied by jaundice, with 13% having jaundice without pain. Jaundice, a yellow tint to the whites of the eyes or skin, with or without pain, and possibly in combination with darkened urine, results when a cancer in the head of the pancreas obstructs the common bile duct as it runs through the pancreas. Unexplained weight loss, either from loss of appetite, or loss of exocrine function resulting in poor digestion. The tumor may compress neighboring organs, disrupting digestive processes and making it difficult for the stomach to empty, which may cause nausea and a feeling of fullness.