Abstract: Objective To discuss the relationship between infestation of Demodex folliculorum and facial epidermal neoplasm. Methods A retrospective analysis was made with the pathological data of 153 cases collected in the recent four years on facial basal cell carcinoma, squamous cell carcinoma, seborrheic keratosis and trichilemmoma. The infection rate of Demodex folliculorum in the four types of neoplasm was evaluated and the relationship between the infection rate and the location of neoplasm and age was analyzed by V2 test. Results There was a significant difference in the infestation rate of Demodex folliculorum in the four types of epidermal neoplasm(P<0.05), with the highest rate in basal cell carcinoma（56%）, compared with seborrheic keratosis(21%), trichilemmoma(20%), and squamous cell carcinoma(14%). The infestation rate of Demodex folliculorum was significantly different in variant locations of epidermal neoplasm (P<0.05). The highest infestation rate was in cases of nasal neoplasm(71%), compared with other parts. In addition, among twelve cases of Demodex folliculorum positive nasal neoplasm, nine were basal cell carcinoma；ten of thirty-six basal cell carcinoma occurred on nose. Conclusion The highest infestation rate of Demodex folliculorum was in cases of nasal epidermal neoplasm compared with other locations, and the cases of basal cell carcinoma showed the highest infestation rate among the four types of neoplasm.

Key words: Demodex folliculorum, Histopathology, Epidermal neoplasm