Background: Epidermal inclusion cysts (EICs) are a common cutaneous disorder in adults. The etiology of EICs remains obscure. Our clinical experience suggests that smoking may be a risk factor for the development of EICs. OBJECTIVE To determine whether the number and sites of EICs are related to smoking behavior and quantity.
Methods and materials: We retrospectively surveyed patients pathologically diagnosed with EICs at our hospital. A control group comprised patients who underwent surgical procedures for diagnoses other than EICs. Smoking history was obtained through telephone or clinical interviews.
Results: Three hundred one patients with EICs were identified in our archives: 217 men (mean age 37.1, range 9-77) and 84 women (mean age 41.3, range 9-82). Detailed medical records and smoking history were available for 225 patients. Two hundred twenty-five age- and sex-matched patients were enrolled in the control group. Results showed that a higher percentage of men with facial EICs than of control subjects were smokers (p<.01). No such association was found in women with EICs.
Conclusion: Smoking may contribute to the development of EICs.