The only way to know will be through addition biopsy. If you choose not to have this removed, (some doctors laser things off, some want to watch them) please look at it regularly (I do not mean annually, I mean at least once a month) for changes in color, texture, size, etc. If anything changes, please get another doctor opinion and another biopsy. But there are no other methods right now for determining that dysplasia will convert to malignancy. In oral dysplasia only about 25% of them treated or not ever move further on to malignancy.