A new test uses a tumor\'s own genomic information to help pathologists and oncologists diagnose challenging cancer cases, U.S. researchers say. Principal investigator Dr. John Kornberg, chief executive officer/president of Cedar Associates LLC, said the Pathwork Tissue of Origin Test is the only U.S. Food and Drug Administration-cleared, Medicare-covered molecular diagnostic for identifying tissue of origin for difficult cancer cases such as those that have spread or have a complex clinical history. In the study, use of chemotherapy regimens consistent with guidelines for the final tumor-site diagnosis increased significantly from 42 percent to 65 percent, a gain of 23 percent, Hornberger said. Overall survival was projected to increase from 15.9 months to 19.5 months, a mean gain of 3.6 months overall survival, the study found. The average increase in survival adjusted for quality of life was 2.7 months. The Tissue of Origin Test significantly altered clinical practice patterns for treating metastatic cancer,\" Hornberger said in a statement. \"We saw an increase in overall survival and quality-adjusted life years, resulting in an expected cost per quality of life year of less than $50,000 per patient, which is within the generally accepted threshold of less than $100,000 for cost-effectiveness in the United States.\" The findings are being presented at the Study of Lung Cancer Joint Conference on The Molecular Origins of Lung Cancer: Biology, Therapy and Personalized Medicine in San Diego.