Cytokeratin fragment 21-1 (synonyms: CYFRA 21-1; cytokeratin 19 fragments) is a component of the cytoskeleton.
CYFRA 21-1 can be used as a so-called tumor marker. Tumor markers are endogenous substances produced by tumors and detectable in the blood. They can provide an indication of a malignant (malignant) neoplasm and serve as a follow-up test in cancer aftercare.
The procedure
Material needed
- Blood serum; sample transport preferably refrigerated (+2 °C – +8 °C) or frozen (approx. -20 °C).
Preparation of the patient
- Not necessary
Disruptive factors
- None known
Standard values
| Normal value | <3.0 ng/ml |
Indications
- Suspected bronchial carcinoma (lung cancer).
- Suspicion of carcinoma in the head and neck area
- Suspicion of cervical carcinoma (cancer of the cervix)
- Urinary bladder carcinoma (bladder cancer) – only for follow-up.
- Therapy / progress control in the above tumor diseases.
Interpretation
Interpretation of increased values
- Bronchial carcinoma (lung cancer; depending on histology: sensitivity (percentage of diseased patients in whom the disease is detected by using the test, i.e., a positive test result occurs) approximately 40-75%).
- Urinary bladder cancer, muscle invasive (urinary bladder cancer; detectable up to 50% of cases).
- Head and neck carcinomas
- Cervical carcinoma (cervical carcinoma; detectable in 30-40% of cases).
- Ovarian carcinoma (ovarian cancer; detectable in 30-35% of cases).
Interpretation of decreased values
- No diagnostic significance
Further indications
In case of suspicion
- Bronchial carcinoma also determine CEA and NSE.
- Urinary bladder carcinoma also determine CEA and TPA
- Cervical carcinoma also determine CA 125 and SCC
