Few screening tests are more uncomfortable for the patient than a colonoscopy — that oh-so-fun procedure during which the doctor inserts a long lighted tube into the rectum and advances it through the entire colon, typically in search of polyps. Even if use of anesthesia makes it painless, most find it rather anxiety-producing.

Yet it is an effective way to screen patients for colorectal cancer (CRC) and is recommended for most adults over 50.

But now, hopefully, there may be a simpler way to identify colorectal cancer according to BioServe (Laurel, Maryland) and Canadian company Phenomenome Discoveries (PDI; Saskatoon, Saskatchewan).

The two companies this week reported that they have developed a new serum-based diagnostic test for the identification of colorectal cancer, and pre-cancerous states conducive to the development of colorectal cancer.

Kevin Krenitsky, CEO of BioServe, told Diagnostics & Imaging Week that the test is unique: he doesn't know of any others like it on the market.

Krenitsky said adults over 50 are recommended to get a colonoscopy to screen for colorectal cancer, but many adults younger than 50 are also at risk for the disease.

For those patients, he said, the blood test may offer an alternative screening method for the disease. If, however, the serum-based test comes back positive, Krenitsky said the patient would be referred for a colonoscopy immediately as a confirmatory measure.

The new colorectal cancer diagnostic test from BioServe and Phenomenome Discoveries is available in Canada and Japan. Both companies anticipate that the test will be available for distribution in the U.S. in 4Q07. The test is also available for use by researchers worldwide as a fee-for-service research tool that allows research-use-only applications, the companies said. Further plans for broad commercialization to physicians and patients are underway.

"The development of this new and novel diagnostic test for colorectal cancer showcases how BioServe successfully collaborates with partners to gain insights to disease at the deep molecular level to advance the science of personalized and predictive medicine," Krenitsky said. "PDI is at the forefront of molecular biomarker research and discovery, and we look forward to the discovery of similar biomarkers in other diseases as a result of our expanded collaboration with PDI and to the development of more 'wellness' enhancing diagnostics."

Colorectal cancer comprises one-tenth of the global cancer burden, and is the third most common malignancy in the world, the companies said. According to the National Cancer Institute, this year alone there have been about 153,760 new cases of colorectal cancer in the U.S. and 52,180 deaths from the disease.

In developing the test, BioServe identified a large number of patient tissue and serum samples from its Global Repository exhibiting CRC across a spectrum of stages, as well as matched healthy controls. Using PDI's non-targeted metabolomics platform, PDI discovered that a series of novel metabolites were significantly decreased in serum samples collected from colorectal cancer patients compared to controls. From these results, PDI developed a two minute high-throughput screening method capable of simultaneously measuring a key subset of these molecules.

BioServe provided a second independent population of 189 CRC samples and 287 controls, and the rapid test was found to be 78% sensitive and 90% specific in this validation sample set, the companies noted.

The test has now been validated in four independent studies, across which the sensitivity of detection for colorectal cancer positive cases averaged 75%, and the specificity averaged 90%. Trials are planned for late 2007 in Canada and Japan, in which healthcare authorities will evaluate the test's utility as part of a broad-based population-screening regimen.

"Early detection is the single most important factor in improving patient survival. The availability of a simple, serum-based, pre-colonoscopy screening test for CRC will have a positive impact on the low compliance rate of colonoscopy as a screening tool and enable healthcare providers to make more efficient use of the colonoscopy in the management of CRC," said John Hyshka, chief operating officer of PDI.

"BioServe's clinical colorectal cancer data and control samples from its vast Global Repository of over 600,000 human DNA, tissue and serum samples were critical to accelerating our research in colon cancer and developing this breakthrough diagnostic test. Based on our success in CRC, we have expanded our collaboration with BioServe to identify serum biomarkers for other forms of cancer as well as multiple sclerosis."

PDI conducts research focused on the biochemical characterization of disease and restoration of metabolic balance. Key areas of focus include cancer and mental health research. It also offers contract biomarker discovery solutions and personalized metabolic health monitoring.

BioServe develops diagnostic tests for the practice of personalized, predictive and preventive medicine. It also offers the Global Repository, a library of more than 600,000 human DNA, tissue and serum samples linked to detailed clinical and demographic data from 140,000 consented and "anonymized" patients from four continents.