Depth of Invasion of Aggressive and Nonaggressive Basal Cell Carcinoma

Objective: Dermal invasion is characteristic of more aggressive basal cell carcinoma (BCC) tumors. However, reporting the depth of invasion of BCC is not currently a standard or recommended practice. The purpose of this study was to document the depth of invasion of BCC. Design: Original hematoxylin and eosin-stained slides of biopsied BCCs (N=500) were reviewed. The depth of invasion was measured for each case. Each case was also determined to be aggressive or nonaggressive based on the presence of additional histologic features. Setting: Biopsy specimens from a large private practice were reviewed. Measurements: Descriptive statistics were calculated for all cases. To compare the average depth of invasion of cases with aggressive features versus cases with nonaggressive features, two-tailed, independent t-tests were computed. Results: The overall median depth of invasion was 0.68mm (range: 0.10–5.49). The median depth of invasion of aggressive cases (n=68) was 1.04mm, while the median depth of invasion of nonaggressive cases (n=432) was 0.62mm. The difference between median depth of invasion of aggressive and nonaggressive cases was found to be significant ( p