Clinical Newswire, January 24, 2010 (Orlando, FL, USA) - A novel immunoassay that detects early-stage pancreatic cancer has been developed, according to research presented at the 2010 Gastrointestinal Cancers Symposium. The assay identifies and quantifies blood levels of the PAM4 protein - a unique biomarker present in almost 90% of pancreatic cancer and its precursor lesions.
Pancreatic cancer has been labeled a "silent killer" because in its early stage it often does not cause symptoms, and in later stages symptoms are usually non-specific, which often delays diagnosis. Also, pancreatic cancer is initially often difficult to distinguish from pancreatitis. “Most patients with pancreatic cancer are diagnosed when the disease is advanced and more difficult to cure”, said study lead author David V. Gold, PhD (Garden State Cancer Center Belleville, New Jersey, USA). Currently, only 7% of pancreatic cancer cases are detected at an early stage and the survival rate for early-stage pancreatic cancer is 20%, with survival rate dropping to only 1.8% for those diagnosed when the cancer has metastasized. The researchers aimed to develop a serum assay that detects early-stage pancreatic cancer with high sensitivity and specificity.
The PAM4 antibody (also called clivatuzumab) used in the assay reacts with a protein produced by pancreatic cancer cells that is not detectable in normal pancreatic cells and is rarely detectable in pancreatitis, making it highly specific for pancreatic cancer.
An immunoassay for PAM4 protein was evaluated in 68 patients who had pancreatic cancer surgery and 19 healthy controls. The assay detected early pancreatic cancer with sensitivity rates of 62% and 86% for stages I and II, respectively. The sensitivity for detection of advanced (stage III and IV) pancreatic cancer was higher at 91%. Overall, the sensitivity and specificity for detecting all stages of pancreatic cancer were 81% and 95%, respectively.
The researchers conclude that these promising results warrant further evaluation to determine this test’s impact on the management of patients with pancreatic cancer. According to Dr Gold, “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 clivatuzumab antibody may also prove useful in the treatment of the disease by acting as carrier for agents that target and kill cancer cells.
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