Down to a depth of 1.5 mm, microanatomical structures were clearly identifiable on the OCT images. Concerning the ability to differentiate non- and early invasive lesions, OCT reached a sensitivity of 100% and a specificity of 92% or 75% (investigator unblinded or blinded to visual inspection), respectively. False positive findings were mostly hyperplastic lesions with a significant broadening of the epithelial layer. Epithelial thicknesses measured on OCT images and histological slides correlated well (κ=0.63), but were no indicators of either epithelial hyperplasia or different grades of dysplasia. Yet, OCT intensity profiles showed a statistically significant difference between dysplastic and hyperplastic lesions in a subset of cases (n=44).