Colon cancer screening with blood plasma
Each year, 27,000 new cases of colon cancer are diagnosed in Spain. It is the most common malignant tumour if both men and women are taken into account. That is why it is important to establish screening programmes for healthy people.
One of every three colon cancer deaths could be avoided if everybody over the age 50 underwent regular screening tests.
The mSept9 test is one of the most effective tests for the early detection of tumours in blood plasma, and it should be done prior to other more invasive diagnostic tests such as a colonoscopy.
This type of test is done on blood plasma, and it detects the presence of methylated septin 9 (mSept9), a new genetic tumour marker that is found in more than 90% of tumours of the colon. It appears in the blood in the form of free DNA.
The presence of mSept9in the plasma indicates the possibility of new growth related to colon cancer. This marker is very infrequently found in other types of tumours.
This test has a specificity of over 88.4% and a sensitivity of 66.7%, which is much higher than current screening techniques based on the identification of occult blood through immunological methods. This leads to fewer false positive and fewer false negative results.
The analysis does not require any special preparation on the part of the patient. It can be done on a full or empty stomach, and it can be integrated into an analytic monitoring program, coinciding with other determinations.
The test is designed to screen for colon cancer in the general population; i.e., in patients who have no symptoms of cancer. In the majority of European countries there are colon cancer screening programmes for both men and women, starting at age 50.
People who have had colon cancer or who have a family history of risk should follow the special instructions of the family oncologist.
A positive result
This means there is a greater likelihood that colon cancer is present. People with positive results are advised to undergo a colonoscopy for a final diagnosis.
A negative result
This indicates that mSept9 has not been identified, although it is recommended that the individual be tested again two years after a negative result.