According to the National Cancer Institute, about 150,000 people in the U.S. will be diagnosed with colorectal cancer this year and 52,000 will die of the disease.

Yet, colorectal cancer can be cured by early removal of suspicious small tumors (polyps) during colonoscopy. That's why the American Cancer Society recommends that everyone have a colonoscopy every 10 years beginning at age 50.

Less than half of Americans follow this advice, however, because they are uneasy about the procedure, which requires an overnight fast, the taking of powerful laxatives, light anesthesia during the procedure, and the insertion of a scope into the rectum. I, too, put off having a colonoscopy until long after age 50 — waiting until worrisome symptoms made me suspect colorectal cancer.

It turned out that the colonoscopy itself was a piece of cake. I awakened surprised to find that the procedure was over and that no discomfort was involved. My previous constant worries were relieved and my spirits buoyed by the good news that no signs of cancer had been found.

I can't deny, however, that the results of taking the laxative the night before were unpleasant and that this part of the pre-op procedure will dampen my enthusiasm for having another colonscopy. But new findings by cancer researchers at Johns Hopkins may make another colonoscopy unnecessary for me.

The Hopkins scientists have found that two proteins in the blood are strongly associated with the presence of colorectal cancer. Their recent study, reported in the journal Cancer Research, compared the new blood test with colonoscopy for the ability of each to detect cancers in 107 patients.

Both the blood test and colonoscopy found cancer in 28 of the patients, and the blood test detected precancerous polyps in 14 of the 18 patients identified by colonoscopy as having such polyps. That is, the new test found all 28 cases of cancer within the group, but missed identifying polyps as the culprit in four of those 28.

The blood test would not replace colonoscopy but it could screen out low-risk people and determine which ones really need colonoscopy. In this way, the blood test for colorectal cancer would play a role similar to that of an exercise stress test, for example, which helps to determines which people with chest discomfort need an invasive procedure like coronary angiography.

The promising results from this small number of patients must be confirmed by the larger studies that are now under way. Completion of the larger clinical trials and possible approval of the test by the Food and Drug Administration will take a couple of years. A strongly positive test might extend the use of colonscopy to younger people.

Meanwhile, it is crucial that all of us age 50 and older continue to undergo the discomfort of the laxative and the indignity of colonoscopy while we hope for a positive outcome of the larger studies that may make the procedure unnecessary for many.