Cigarette smoking has been associated with an increased incidence of pancreatic cancer. Long-term exposure to certain chemical carcinogens, such as dry cleaning chemicals, or gasoline or metallurgic fumes, also appears to increase the risk of this cancer. Research has yielded conflicting data on the causative roles of alcohol and coffee. Although an increased incidence is observed in patients with chronic pancreatitis and diabetes mellitus, it has been suggest that the onset of pancreatic insufficiency may occur months before the cancer becomes clinically apparent. There are few early signs and symptoms of pancreatic cancer, and this complicates diagnosis.
Many patients wait until the symptoms become worse before visiting a physician.
Seventy percent of all pancreatic cancers appear in the head of the gland. Early diagnosis of a tumor in the head of the pancreas is sometimes possible because of jaundice and pruritus that result from biliary obstruction. Pain is usually the complaint that motivates patients to seek a physician's care. Almost all patients with pancreatic cancer will have pain at some point in their disease, caused by pressure from the tumor or by infiltration of the splenic nerves. Patients with cancer in the body or tail of the pancreas frequently experience back or abdominal pain.