For most oral cancer patients the odds of recurrence decline sharply at two years and at five years. Missed micro metastasis rear their heads in the first two years, as do particularly aggressive forms of the disease. By 5 years, most of those kinds of things are out of the way, so survival numbers go up. But no one can know the meaning of most of the genetic predisposition's that make you who you are, to be protected from - or susceptible to, getting a second cancer.