A little high non-small cell lung cancer antigen is serious if it is caused by a malignant tumor, and may be serious or less serious if it is caused by a benign disease. Non-small cell lung cancer antigen refers to cytokeratin 19 fragment, also known as CYFRA21-1, which is the tumor marker of choice for non-small cell lung cancer. Cytokeratin 19 fragments are found primarily in organs such as the lungs, breast, gastrointestinal tract, bladder, and uterus, where both benign and malignant lesions can lead to their elevation. Elevated non-small cell lung cancer antigen due to benign disease is mostly mildly elevated. Higher NSCLC antigen is commonly found in benign diseases such as tuberculosis, pneumonia, mastitis, cystitis, etc. However, in the case of severe pneumonia, tuberculosis, etc., the condition may be more serious or even life-threatening; while mastitis, cystitis, etc. are mostly less serious. Non-small cell lung cancer, breast cancer, bladder cancer, prostate cancer, cervical cancer and other malignant tumors may also lead to high non-small cell lung cancer antigen, which is usually more serious and requires radical surgery, radiotherapy and other treatments as soon as possible. It is recommended to combine other tumor markers and imaging results to determine the cause of the disease, and follow the doctor’s instructions for further examination and treatment.