The presence of severe dysplasia was a highly significant predictor of active disease status ( P = 0.007); severe dysplasia and carcinoma-in-situ showed a 4.6 and a 4.8 times increased risk, respectively, for active disease compared to mild dysplasia.
SCC development distant from primary lesion sites was only seen in intermediate or major sized lesions, and although nonsignificant ( P = 0.104, Fisher's exact test), there was a definite trend for lesions >200 mm 2 to exhibit further disease, malignant transformation, and SCC development following treatment. 3.6.