Association of smoking with common follicular cysts

To the Editor: Hair follicles commonly form 2 types of cysts. Epidermal inclusion cysts (EICs) result from follicular injury or occlusion and occur sporadically. Trichilemmal cysts (TCs) are neoplasms that develop from the outer follicular root sheath. These cysts present either sporadically or in an autosomal dominant pattern due to a variant in the PLCD1 gene.1 Hidradenitis suppurativa is severalfold more prevalent in smokers and, like EICs, related to follicular occlusion.2 Lin et al found that male smokers may be more likely to develop facial EICs.