According to the Spanish Association Against Cancer, in our country about 64% of people who suffer from a colorectal tumor survive more than five years. The figure could rise dramatically if a new healing method that has just been tested in mice achieves the same effectiveness in humans in future clinical trials.
The novel technique uses nuclear medicine to remove the tumor. In tests with rodents, researchers have achieved a cure rate of one hundred percent, and without the harmful sequelae that these treatments entail.
The experiment, just published in The Journal of Nuclear Medicine, is the result of the collaboration of specialists from the Massachusetts Institute of Technology (MIT) and the Memorial Sloan Kettering Cancer Center in New York.
Exterminate without damaging
This new method is based on radioimmunotherapy, a combination of radiotherapy and immunotherapy. How does it work? Monoclonal antibodies attached to radioactive materials called radiosondes are injected into the patient’s bloodstream. Upon reaching the patient’s blood, these antibodies bind to cancer cells (photo) and kill them with radiation. However, this method has limited effectiveness and causes harm to the patient.
What does the new rodent trial contribute? According to Steven M.Larson and Sarah Cheal, two of the researchers who have participated in it, “this work is novel because it achieves its objective without radiation damaging healthy tissues.”
To achieve this, specialists use the so-called theranostic agents, a term derived from the union of the words “therapy” and “diagnosis.” These agents – the aforementioned antibodies loaded with radioactivity – find cancer cells in the patient’s body and then destroy them. In this way, they do not harm healthy cells, which minimizes the effects of therapy on the affected person and improves their quality of life.
In this test, glycoprotein A33, a tumor antigen unique to malignant cells and found in 95 percent of primary and metastatic colorectal tumors in humans, was attacked with a specific antibody against it and a second antibody armed with a small molecule radioactive. Result: all mice cured, and no side effects.
Larson and Cheal believe that this system could be used against other types of cancer: “If clinical trials go well, it will increase the repertoire of effective cancer treatments. We have developed the technique keeping in mind that it can be applied to various tumors, such as those of the pancreas , chest, lung and esophagus, to name a few ”.
An increasingly common cancer
According to data from the Spanish Association Against Cancer, “Colon cancer is increasing in incidence in western and developed countries. In Spain between 28,500 and 33,800 new cases are diagnosed each year, about 20,000 in men and 14,000 in women. Colon cancer will affect 1 in 20 men and 1 in 30 women before the age of 74 ”.
Preventing colorectal cancer completely is a utopia, but specialists give guidelines to do so as far as possible. It is important to undergo periodic screening tests from the age of 50, even if there are no symptoms, and earlier if there is a family history.
Several studies have found that the risk of suffering from this tumor increases with being overweight, smoking, lack of physical activity, alcohol consumption and an inadequate diet. Limiting red and processed meats and eating more fruits and vegetables may help lower their incidence.
Image: Human colon cancer cells. Photo from the US National Cancer Institute.
