Characterization of Basal Cell Epithelioma in the Japanese

Clinicopathological and statistical studies were made on one hundred and fifty‐six Japanese cases of basal cell epithelioma. A new formula was presented for the calculation of the growth rate of BCE, as follows, Size of tumor (major axis × minor axis) (mm2) = 1.7363 × T2 + 133.1192 T = Years which had elapsed from the presumed time of onset to the time of the first examination The yearly growth in diameter calculated from the above formula is less than 1.0 mm within ten years after onset, and 1.0 mm to 1.3 mm thereafter. The time needed for BCE to double its size averaged 8.8 years in the present study. In addition to the slow rate of progression, BCE in the Japanese was characterized by its pigmentation; 84% were either partially or totally pigmented, giving the BCE the so‐called black and pearly appearance.