| New
serum protein profile testing accurately distinguishes prostate cancer
from benign conditions Serum protein patterns can distinguish prostate cancer from benign prostate disease, according to an article in the October 16th issue of the Journal of the National Cancer Institute. The new technique, which relies on a simple test using one drop of blood, may be clinically useful in deciding whether to perform a biopsy in men with elevated prostate specific antigen levels. The American researchers were able to differentiate between samples taken from patients diagnosed with cancer and those from patients diagnosed with benign prostate disease. The technique proved effective not only in men with normal and high prostate specific antigen levels, but also in men with marginally elevated levels (4 to 10 ng/mL), a group in whom it is difficult to rule out cancer without a biopsy. In current practice, prostate specific antigen levels are commonly used as a preliminary screen for prostate cancer. However, 70 to 75 percent of men who undergo biopsy because of an abnormal antigen level have benign disease. The new proteomic approach has a higher specificity than traditional prostate specific antigen testing. "For men with marginally elevated prostate specific antigen levels, the specificity of the test is 71 percent, as opposed to a very low specificity for prostate specific antigen in this range," said Emanuel Petricoin III, Ph.D., lead author of the study. "We hope that by using proteomic pattern analysis screening in combination with other screening methods, we can reduce the number of unnecessary biopsies for prostate cancer in the future." The diagnostic test relied on computer software that detects key patterns of small proteins in the blood. Researchers analyzed serum proteins with mass spectroscopy, then used an artificial intelligence program to train a computer to identify protein patterns that differed between patients with prostate cancer and those in whom a biopsy had found no evidence of disease. These patterns were identified using serum samples from 56 patients who had undergone a biopsy and whose disease status was known. Once established, the protein patterns were then used to predict diagnosis in a separate group of patients, whose biopsy results were not known by the researchers. From this group, researchers were able to correctly identify 36 of 38 (95 percent) cases of prostate cancer and 177 of 228 (78 percent) cases of benign disease. The current study follows recent finding by the same research group that protein patterns in serum can be used to detect ovarian cancer. "We have now demonstrated that combining proteomic technology with artificial intelligence-based bioinformatics can be a powerful tool, and is a new paradigm in the detection and diagnosis of both ovarian and prostate cancers," said Lance Liotta, M.D., Ph.D., the senior investigator on the study. "We are extremely
optimistic that this new approach will prove useful in detecting
and diagnosing many other cancers and diseases in the future." |