The New York State Health Department approved a blood test for colon cancer screening this past week. Administered by Quest Diagnostics, ColoVantage is a blood test which screens patients for the presence of colorectal cancer.
What is ColoVantage?
ColoVantage is a blood test to detect colorectal cancer. The other name of the test is methylated Septin 9. The test requires a venous blood specimen from a patient, with no advance preparation by the patient. Upon laboratory analysis of the blood, circulating methylated DNA is detected from the SPT 9 gene in the presence of cancer cells. Quest Diagnostics reports this test has 70 percent sensitivity and 89 percent specificity for colorectal cancer detection.
Some statistics about colorectal cancer
According to the American Cancer Society, colorectal cancer ranks third as the most common cancer in the U.S. In 2011, there were over 100,000 new cases of colon cancer and almost 40,000 new cases of rectal cancer. Although the death rate for colorectal cancer has been decreasing in the past few years, almost 50,000 deaths will be attributed to colorectal cancer this year in the U.S. alone.
With increasing numbers of people getting screened, colorectal cancers are found earlier and are treated, causing the death rates to drop. Currently in the U.S. there are over a million colorectal cancer survivors.
Who should consider ColoVantage?
It is important to note that ColoVantage is not a replacement for colonoscopy, which is considered the gold standard in colorectal cancer screening for patients over the age of 50. Jay G. Wohlgemuth, M.D., vice president, science and innovation, Quest Diagnostics, stated that "ColoVantage cannot replace colonoscopy, and it has yet to be validated for colon cancer screening." The American Cancer Society reports that only half of the people over 50 have been screened, and for those who refuse a colonoscopy, ColoVantage offers a noninvasive alternative with a simple blood test and no preparation, unlike the more involved colonoscopy procedure.
If the ColoVantage test results are positive, then the recommendation for the patient is to have a follow up colonoscopy, as anyone who shows positive results on a ColoVantage test is at an increased risk for colorectal cancer. Since this is relatively new, FDA has not yet approved this test as a screening measure and many insurance companies, such as Aetna, consider testing using methylated Septin 9 (ColoVantage) "experimental and investigational."