By Gene Emery
BOSTON (Reuters) - Researchers in Italy said on Wednesday they have developed a test that identifies most people with autoimmune pancreatitis, which could make it easier for doctors to distinguish it from pancreatic cancer, one of the deadliest types of cancer.
But the method is not perfect. While it gave a correct diagnosis in 94 percent of cases, 5 percent of people with pancreatic cancer falsely tested positive for the less-serious inflammatory condition.
"Therefore (it) cannot be used alone to distinguish autoimmune pancreatitis from pancreatic cancer," Dr Luca Frulloni of the University of Verona and colleagues wrote in the New England Journal of Medicine.
The pancreas makes hormones that control how the body metabolizes food. People with autoimmune pancreatitis often suffer symptoms such as jaundice or abdominal pain.
Its symptoms are similar to those of advanced pancreatic cancer and it can be difficult, using x-rays known as CT scans or other scans, to distinguish between the two diseases, Dr Antonio Puccetti of the University of Genoa, who also worked on the study, said by email.
As many as 10 percent of patients who have the pancreas removed because they are believed to have pancreatic cancer actually have autoimmune pancreatitis, an easily treated condition.
"Since this disease responds dramatically to steroid treatment, the correct diagnosis is important to avoid unnecessary surgery in some patients," Frulloni said.
On the other hand, pancreatic cancer can progress rapidly. The fear is that some patients with operable cancer may be incorrectly treated with steroids based on the belief that they have autoimmune pancreatitis.
"A diagnosis of pancreatic cancer should be safely ruled out before the use of steroid treatment," said Frulloni. "A diagnostic test is therefore of a great importance from a clinical point of view."
Volunteers with other immunity diseases or pancreatitis caused by alcohol, which is far more common, did not show evidence of the telltale antibody detected by the test.
Frulloni said the results need to be confirmed and there are no plans, as yet, to market the test.
(Editing by Maggie Fox and Eric Beech)