Postauricular linear basal cell carcinomas related to medical mask cords: a possible association.

Linear basal cell carcinoma (BCC) is a distinct clinical morphological variant of BCC. Although it has been speculated that trauma and the Koebner phenomenon may be linked to linear BCC, the pathophysiology has not yet been shown. Herein, 5 cases of BCC were presented that developed in the postauricular region as a result of trauma caused by the cords of the medical face masks worn during the COVID-19 pandemic.