News from ASCO GI Conference: Researchers develop early-detection test for pancreatic cancer

23 Jan 2010

Researchers have developed a novel immunoassay for detecting early-stage pancreatic cancer that
identifies and quantifies blood levels of the PAM4 protein – a unique antigen present in almost 90 percent
of pancreatic cancers and precancers.

“Most patients with pancreatic cancer are diagnosed when the disease is advanced and more difficult to
cure,” said lead author David V. Gold, PhD, a member of the Garden State Cancer Center in New Jersey.
“In this study, we found that the PAM4 protein is quite accurate at identifying patients with pancreatic
cancer and, if validated in larger studies, would be a promising tool for detecting this disease in its earlier,
more treatable stages, before it spreads to other organs.”

The PAM4 antibody (also called clivatuzumab) used in this assay reacts with a protein produced by
pancreatic cancer cells. The protein is not detectable in normal pancreatic cells and is rarely detected in a
non-cancerous condition, called pancreatitis (inflammation of the pancreas), making it highly specific for
pancreatic cancer. (Pancreatic cancer is initially often difficult to distinguish from pancreatitis.)

The researchers evaluated an immunoassay for the PAM4 protein in 68 patients who had pancreatic
cancer surgery and 19 healthy controls. They found that the test was 62 percent sensitive for detecting
stage 1 pancreatic cancer (disease confined to the pancreas), 86 percent sensitive for stage 2 disease
(disease which has spread to nearby organs) and 91 percent sensitive for stage 3/4 cancers (local and
distant spread). The assay was 81 percent sensitive for detecting all stages of pancreatic cancer.

The investigators concluded that these promising data warrant further evaluation to determine how the
test can improve the management of patients with pancreatic cancer. If these results are confirmed, it may
become possible to test people at risk for pancreatic cancer (patients with a history of tobacco use, or
those with genetic or other medical factors) on a yearly basis, to enhance the chance of early detection.
Currently, just 7 percent of pancreatic cancer cases are detected at an early stage, before the cancer has
spread to other parts of the body. The survival rate for early-stage pancreatic cancer is 20 percent,
compared with just 1.8 percent for those diagnosed when the disease has metastasized.

The investigators noted that the clivatuzumab antibody may also prove useful for treating the disease by
acting as a carrier for agents (such as radioactive isotopes) that can target and kill cancer cells.