Why the idea of a "blood test for cancer" seems logical, but doesn't always work<\/h3>\n
Tumor markers are substances that can be produced by tumor cells or tissues in the body in response to a pathological process. However, they are not unique to malignant tumors.<\/p>\n
Their level may increase with:<\/p>\n
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chronic inflammation<\/p>\n<\/li>\n
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benign neoplasms<\/p>\n<\/li>\n
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infections<\/p>\n<\/li>\n
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hormonal changes<\/p>\n<\/li>\n
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age-related characteristics<\/p>\n<\/li>\n
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the influence of smoking or other lifestyle factors<\/p>\n<\/li>\n<\/ul>\n
That is why a result above the norm does not automatically mean an oncological process.<\/p>\n
According to recommendations World Health Organization<\/span><\/span>, effective screening should be based on methods with proven benefits for the population, not just on laboratory indicators.<\/p>\n
Main problem: low specificity<\/h3>\n
For screening, it is important that the test clearly distinguishes patients from healthy individuals. Most tumor markers have limited specificity.<\/p>\n
This means:<\/p>\n
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possible false positive results<\/p>\n<\/li>\n
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unnecessary examinations<\/p>\n<\/li>\n
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unnecessary invasive procedures<\/p>\n<\/li>\n
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psychological stress<\/p>\n<\/li>\n<\/ul>\n
Specialists Mayo Clinic<\/span><\/span> emphasize that tumor markers are much more effective for monitoring an already established diagnosis than for the initial search for a tumor.<\/p>\n
When tumor markers can still be part of a screening strategy<\/h3>\n
There are situations where cancer marker testing is used in narrow risk groups. But even then, it is not used in isolation.<\/p>\n
\n\n\n\n
\n \nTumor marker<\/th>\n Who may be relevant?<\/th>\n Important conditions<\/th>\n<\/tr>\n<\/thead>\n \n PSA<\/a><\/td>\n Middle-aged and older men<\/td>\n Discussion with a doctor<\/td>\n<\/tr>\n \n AFP<\/td>\n Patients with chronic liver disease<\/td>\n Regular monitoring<\/td>\n<\/tr>\n \n CA-125<\/td>\n Individuals with high hereditary risk<\/td>\n Combination with ultrasound<\/td>\n<\/tr>\n \n CEA<\/a><\/td>\n After tumor treatment<\/td>\n Dynamic control<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n In each case, the decision is made individually.<\/p>\n
Screening and monitoring: two different goals<\/h3>\n
Screening is the search for a disease in people without symptoms.
Monitoring is the control of the condition after diagnosis or in a high-risk group.<\/p>\nTumor markers are most informative for:<\/p>\n
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evaluation of the effectiveness of therapy<\/p>\n<\/li>\n
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early detection of relapse<\/p>\n<\/li>\n
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progression control<\/p>\n<\/li>\n<\/ul>\n
In such cases, changes in dynamics are more important than absolute numbers.<\/p>\n
Why \u00abgiving all tumor markers for prevention\u00bb does not increase safety<\/h3>\n
Preventive testing without an indication may create the illusion of control, but does not guarantee early detection of cancer. A normal result does not exclude the disease, and a moderate increase often turns out to be non-oncological.<\/p>\n
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![\"laboratory](\"https:\/\/medilab.km.ua\/wp-content\/uploads\/2026\/02\/1102.jpg\")
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