The significance of lung cancer erbb2 gene: positive aids in the diagnosis of lung cancer or suggests the prognosis of cancer staging. 1. Auxiliary diagnosis of lung cancer: erbb2 gene is a proto-oncogene, also known as HER-2 gene or neu gene, which is expressed in malignant tumor diseases such as breast cancer, stomach cancer, ovarian cancer and so on. This gene is usually not expressed or lowly expressed in the normal population. When patients have amplification or overexpression of the above gene, it can assist in the diagnosis of lung cancer. 2. Indication of cancer stage and prognosis: the expression of erbb2 gene in different tissues may have obvious differences. Take non-small cell lung cancer as an example, the positive expression of erbb2 gene in lung cancer with lymph node metastasis is about 43.8%, while in lung cancer without lymph node metastasis the expression is only 7.14%, so this gene can be used to indicate the presence of metastasis of the cancer and to indicate the prognosis. 3. Others: Lung cancer erbb2 gene expression can be used in clinical research and evaluation of many kinds of tumors, and it can also be used to indicate whether there is the possibility of multidrug resistance, which is of great significance for clinical guidance of drug use. erbb2 gene is now commonly used as an independent indicator for judging the prognosis of breast cancer. Lung cancer patients should go to regular hospitals for erbb2 gene test, consult with doctors about the test results and formulate appropriate treatment plans to avoid cancer development and life-threatening situations.