Overall survival stratified according to tumor thickness.

a95%-CI = 95% confidence interval; bp-values are results of log rank tests excluding cases with missing values. c2 patients had unknown mitosis and in 3 cases censoring occurred before the first event was observed; the model was adjusted for the confounding effects of tumor thickness (n = 234). d2 patients had unknown mitosis rate and in 1 cases censoring occurred before the first event was observed; the model was adjusted for the confounding effects of mitotic rate and BRAF-V600 mutations (n = 195). na = not available.