Non-small cell lung cancer antigen 21-1 is high at 3.44ng/ml suggesting the possible presence of benign and malignant diseases of the lungs, gastrointestinal tract, urinary system, and gynecology. Non-small cell lung cancer antigen 21-1 refers to cytokeratin 19 fragment, also known as CYFRA21-1, which is the tumor marker of choice for non-small cell lung cancer, mainly found in breast, lung, intestine, bladder, uterus and other epithelial tissue-rich places. The normal value of CYFRA21-1 ranges from 0 to 3.3 ng/ml. 3.44 ng/ml is a mild increase, suggesting that chronic bronchitis, tuberculosis, pneumonia, and benign diseases of gynecology, gastrointestinal tract, urinary system, or malignant tumors such as non-small-cell lung cancer, breast cancer, prostate cancer, etc., may be present. It is recommended that the patient should consult the doctor in time, follow the doctor’s instructions for further examination, analyze the cause of the disease comprehensively by integrating the tumor index, inflammation index, imaging examination and so on, and actively treat the disease.