The clinical significance of cytokeratin 19 fragment (CYFRA 21-1)

        It exists in tumor cells of epithelial origin such as lung cancer and esophageal cancer. It is a more sensitive marker for detecting non-small cell lung cancer (NSCLC).

1. Screening
        Serum CYFRA 21-1 is generally not used for lung cancer screening.

2. Auxiliary diagnosis
        ① Serum CYFRA21-1 is one of the first-choice markers for non-small cell lung cancer, especially squamous cell carcinoma, which has auxiliary diagnostic value.
        ② Serum CYFRA21-1 also has different degrees of positive rates in other malignant tumors, such as bladder cancer, esophageal cancer, nasopharyngeal cancer, ovarian cancer and cervical cancer.
        ③ Serum CYFRA21-1 may also increase to a certain extent in certain benign diseases, such as hepatitis, liver cirrhosis, pancreatitis, pneumonia, tuberculosis, etc., but the positive rate is low. Renal failure can lead to an increase in serum CYFRA21-1.

3. Prognosis assessment
        Serum CYFRA21-1 is an important prognostic indicator for non-small cell lung cancer. Serum CYFRA21-1 continues to rise, indicating a poor prognosis.

4. Efficacy and recurrence monitoring
        ① Serum CYFRA21-1 can be used to monitor the efficacy of non-small cell lung cancer. The continuous increase in the concentration of CYFRA21-1 indicates disease progression.
        ② Serum CYFRA21-1 can be used for follow-up and recurrence monitoring of non-small cell lung cancer. Generally, it should be tested every 3 months within 2 years after treatment, and every 6 months within 3 to 5 years.