MKI67 and neoplasm: The proliferation fraction is typically low, with few or no mitoses, and a Ki67 fraction of <20%.4,5,7–19 Nevertheless, otherwise, typical tumors may have 1 or several unusual pathological features without apparent clinical significance; these include focal epidermotropism and Pautrier microabscesses, cytotoxic activation markers, and higher proliferative fractions.4,5,21,22 Wobser et al and Kempf et al demonstrated a uniform, peculiar, dot-like pattern of CD68 expression by the neoplastic cells6,23 and suggested that this was a highly sensitive and specific feature of this tumor.