Vacutainer blood bottles.
(photo credit: Wikimedia Commons)
An Israeli-developed automated- screening test for levels of hemoglobin and other substances in the blood of people over age 50 who have not undergone a colonoscopy to detect colorectal cancer in the previous 18 months has been described as a breakthrough by Maccabi Health Services.
The research and development of the product was conducted by Prof. Varda Shalev, head of Maccabitech, the business development arm of the Maccabi Group that includes Maccabi Healthcare Services. The patent-pending product itself – MeScore CRC – is being marketed by Medial Research, a company near Hod Hasharon.
MeScore performs risk stratification and calculates a personal risk score, which has proven a reliable indicator of the need for further testing, Shalev told The Jerusalem Post on Tuesday. The computerized screening tool has been licensed by the Health Ministry in Jerusalem and the CE in Europe and is in the process to receive approval from the US Food and Drug Administration.
Shalev said the product is being tested by the huge Kaiser Permanente health maintenance organization in the US and the University of Oxford, and that various HMOs around the world including Britain’s National Health Service have shown interest.
The system will be offered for sale by Medial to the three other Israeli health funds – Clalit, Meuhedet and Leumit – and not reserved by Maccabi only for itself. The screening will be launched in a the next few months.
Maccabi, the second-largest health fund, maintains that the algorithm-based test, which is conducted on blood samples taken for other conditions, will save the lives of hundreds in Israel annually.
It has long been known that people with full-fledged colorectal cancer lose blood and thus have less hemoglobin.
But there are other reasons for anemia (inadequate amounts of hemoglobin and iron), including excessive menstrual blood and an inadequate diet.
Between 30 percent and 40% of Israelis over the age of 50 decline even to have their stool tested for occult blood – an easy, non-invasive test. People generally undergo invasive colonoscopies to look for precancerous polyps or malignant tumors only if they have a first-degree family member who had colon cancer, had polyps or cancer themselves, or are over 50.
The MeScore algorithm looks at 18 factors including hemoglobin, MCH and thrombocytes in the blood – the same factors tested in occult-blood tests – in blood samples taken from patients over 50 for other reasons. Shalev and her team noticed that many of the people with polyps or colon cancer may have hemoglobin levels within the norm, but lower than usual, so their doctors would not ordinarily call them in for a colonoscopy.
The blood test would catch cases in which the hemoglobin levels are not significantly lower, and takes into consideration the age, sex and other findings in blood tests to rate the risk.
“Everyone has his own norm of hemoglobin and other blood factors,” Shalev said.
Shalev and her colleagues published a study five years ago in the European Journal of Cancer Prevention on variations in hemoglobin before colorectal-cancer diagnosis. With their additional research and clinical trials, they are now preparing an updated journal article on their algorithm.
Shalev said there is no 100% accurate test, with no false-positives and false-negatives, but screening the population’s blood for high-risk factors will mean they will be sent for colonoscopies on time.
“People who do occult-blood tests every year and each time it’s negative will want to stop doing it, but that means they face the risk of colorectal cancer not being detected,” she said.
To cope with the expected greater demand for colonoscopies among people automatically called in by their doctors after their blood is screened, Maccabi has assembled additional gastroenterologists who can do the invasive tests without a long waiting list.
More than 4,000 Israelis are diagnosed with colorectal cancer each year, 1,000 of them in later stages for which the cure rate is lower because the precancerous polyps that could have been removed easily in a colonoscopy turn into malignant tumors that are much harder to remove.