Non-small cell lung cancer antigen 3.53ng/ml is higher than normal, suggesting the possible presence of pneumonia, tuberculosis, and diseases such as lung cancer and breast cancer. Non-small cell lung cancer antigen is also known as cytokeratin 19 fragment, CYFRA21-1. cytokeratin 19 fragment is mainly found in organs rich in epithelial tissues, such as lungs, uterus, mammary glands, prostate, etc., and is elevated when these organs have benign diseases, such as inflammation, or malignant changes. The normal value of cytokeratin 19 fragment is 0~3.3ng/ml, so 3.53ng/ml is higher than the normal value, which is a mild increase. Mildly elevated cytokeratin 19 fragment is mostly seen in benign diseases such as pneumonia, chronic bronchitis, tuberculosis, gynecological and urological diseases, and also in malignant tumors such as non-small cell lung cancer, colorectal cancer and bladder cancer. It is recommended that the patient should consult the doctor in time, analyze the results of other tumor indicators and follow the doctor’s instructions for further examination and treatment.