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Laboratory diagnostics of oncology: which tests help detect cancer

Every year, millions of people are faced with cancer. But the main thing to know is that cancer is often successfully treated if detected at an early stage. It is laboratory diagnostics that allows us to suspect a malignant process even before symptoms appear. This is not only a detection tool, but also a way to monitor the effectiveness of treatment and prevent relapse.
Why is laboratory diagnostics needed in oncology?
Laboratory tests do not diagnose cancer on their own, but they do allow:
detect the first disturbances in the body's functioning
suspect a neoplasm in the absence of symptoms
assess the extent of tumor spread
monitor the course of treatment and detect relapse
The most important tests for suspected oncological pathology
Complete blood count (CBC)
The first and mandatory step in diagnosis. May indicate:
anemia of unknown origin
persistent increase in ESR (more than 30 mm/h)
decreased platelet levels
atypical cells in a smear
Biochemical blood test
Assesses the functional state of organs. Elevated liver enzymes, alkaline phosphatase, bilirubin, or calcium may be indirect markers of the tumor process.
Urine, feces, sputum analysis
Traces of hidden blood, proteins, and atypical cells characteristic of oncological processes may appear in these biological fluids.
Tumor markers
These are substances that are normally either not found in the body or are present in very small amounts. Their levels increase in some types of malignant tumors. They are not absolute proof of the presence of cancer, but their dynamics are very important in monitoring.

Tumor markers in laboratory diagnostics of oncology
| Tumor marker | Application area | Features of interpretation |
|---|---|---|
| CA-125 | Ovaries | Also increases with cysts, endometriosis |
| PSA | Prostate gland | Used for screening and treatment monitoring |
| CEA | Stomach, intestines, lungs | May increase with smoking and inflammation |
| AFP | Liver, testicles | Important in the initial diagnosis of hepatocellular carcinoma |
| CA 19-9 | Pancreas | Limited sensitivity in the early stages |
| NSE | Lungs (small cell lung cancer) | Sensitive to neuroendocrine tumors |
| SCC | Cervix, esophagus | Also increases in benign dermatological conditions |
Other important studies
Pap test
Cytological examination of a cervical smear allows you to detect precancerous changes and early stages of cancer.
Fecal occult blood test (iFOBT)
Performed during colorectal cancer screening. Detects blood in the stool that is not visible to the naked eye.
Genetic testing
Helps determine hereditary predisposition to certain types of cancer, including breast and ovarian cancer (BRCA1/BRCA2 mutations).
When to get diagnosed
after 40 years of age - for preventive screening
if there is a family history of cancer
when inexplicable symptoms appear: rapid fatigue, loss of appetite, weight loss
when detecting nodes, seals, pain or bleeding of unknown origin
before starting hormone therapy, pregnancy, surgery
How to prepare for tests
to be taken on an empty stomach, preferably in the morning
eliminate fatty foods and alcohol for 24 hours
limit physical activity per day
avoid stress before the exam
tell your doctor about all the medications you are taking
What is important to remember
Laboratory tests are a diagnostic step, not a verdict
Tumor markers may be elevated in non-cancer conditions
no marker is used as the sole method
interpretation of results should only be done by a doctor
Regular preventive check-ups can save lives
Laboratory diagnostics is a safe, affordable, and effective tool that can be crucial in the early detection of cancer. Don't ignore routine examinations—they can save your life.
