Is severe dysplasia cancer?

Clinically, severe dysplasia refers to active proliferation of cells involving more than 2/3 of the epithelium, accompanied by dysplasia. Severe dysplasia is not cancer, but severe dysplasia is difficult to reverse and may turn into cancer. Many severe dysplasia are called precancerous lesions. Because many severe dysplasias are not easily reversible and may progress to cancer, early management, including prophylactic surgery, should be given to severe dysplasias to prevent further progression to cancer.