The biopsy specimen from the left cheek measured 0.1 × 0.1 × 0.1 cm. Microscopic sections showed a lobular proliferation of keratinocytes. Some keratinocytes were enlarged and have a foamy vacuolated cytoplasm in the center of the lesion. Other keratinocytes were lost their nucleus and were brightly eosinophilic (Fig. 6.2).