TUSTIN, Calif. ( TheStreet) -- Radient Pharmaceuticals' ( RXPC) Onko-Sure does a lousy job of detecting early-stage colon cancer. How bad? Well, let's just say that a coin flip would be more accurate. Newly released performance data reveals that the Onko-Sure blood test, when combined with an older blood test, successfully detected the presence of early (stage 1) colon cancer in 48% of positive samples tested. "Highly promising" is how Radient described the new Onko-Sure data in a statement released Monday. Patients and doctors interested in catching colon cancer early so that it can be more easily treated and cured will surely disagree. The most desirable time to detect cancer in the colon is before fast-growing cells become malignant. Exact Sciences ( EXAS) is developing a test that detects genetic abnormalities in stool samples. In preliminary studies to date, Exact's Cologuard has been able to successfully detect pre-cancerous lesions in 59% of samples tested. The same Cologuard test has been able to detect 100% of stage 1 colon cancer and 96% for colon cancer in stages I-III combined. Those are data that I'd rightfully call "highly promising." By comparison, the combination of Radient's Onko-Sure plus the older blood test managed a sensitivity, or positive detection rate, of just 58% for all four stages of colon cancer. The tests also had a 40% false positive rate, which means they detected the presence of colon cancer in samples where no cancer actually existed. The new Onko-Sure screening data were made public at last week's American Society of Clinical Oncology's Gastrointestinal Cancers Symposium. The results come from the so-called "Mayo Clinic" study, which Radient conducted after buying colon cancer samples from a subsidiary of the Mayo Clinic. Last year, Radient tried to mislead investors into believing that it was working in partnership with Mayo on the Onko-Sure test. Radient past public statements about findings from the Onko-Sure colon-cancer screening study don't accurately describe the actual data released last week. Radient markets Onko-Sure today as a test used by doctors to detect when colon cancer recurs in patients after treatment. The commercial opportunity for cancer recurrence tests is small and Radient has done a very poor job of selling Onko-Sure, evidenced by the company's dearth of revenue and a balance sheet which makes Greece look like a European economic giant.