Having ulcers in your mouth all the time does not necessarily mean that you have cancer. Because there are many kinds of ulcers in the mouth, the most common one may be herpes simplex in the lip area, because herpes simplex itself is easy to recur, and once it recurs, it may show symptoms of erosion or even ulcers. It may also be aphthous ulcers in the mouth, which is an easily recurring oral ulcer disease and is not directly related to cancer. There is also lichen planus inside the mouth, as lichen planus may have recurrent ulcers once it flares up and does not heal easily. However, lichen planus in the oral cavity has a certain rate of malignancy, so it needs to be treated aggressively for lichen planus in the oral cavity.