Oral cancer ulceration and pus discharge indicate that the tumor cells and cancer cells are locally invasive and infiltrative, which is quite severe. Since the mouth communicates and comes into contact with the external environment, bacterial infection is inevitable. Thus, ulceration often coincides with bacterial infection, leading to inflammation and pus discharge, which can infect others. In terms of infection, bacteria can definitely be transmitted through direct contact and bodily fluid contact. However, it is generally believed that tumor cells are not transmitted to others via direct contact or bodily fluids, considering that a normal person has a functioning immune system capable of recognizing and destroying a small number of tumor cells. Additionally, the likelihood of tumor cells from one person being transmitted to another through bodily fluids is considered very low.