Tumor markers are produced by tumor cells, but normal tissue cells do not produce or produce very little of them, so tumor markers only play an auxiliary role in cancer diagnosis. In addition, tumor markers play a supporting role in monitoring changes in disease and assessing the efficacy of treatment. The final diagnosis of cancer needs to be clarified by histopathological examination. It is not comprehensive to rely on tumor markers alone to determine whether cancer is present, but histopathological testing is also needed to determine whether cancer is present, which can be obtained by puncture biopsy or excisional biopsy.