Ear Keloid as an Unusual Complication of Prolonged Mask Use during the COVID-19 Pandemic

The recent COVID-19 pandemic required many people to wear ear-loop face masks (ELFMs) for protracted periods, and ear injuries have been reported. Here, we report a rare case of a keloid on the right posterior ear that appeared to arise from prolonged ELFM use. A 76-year-old Japanese man presented with a 7.3 x 2.2 x 1.4-cm keloid running from the medial retroauricular sulcus to the posterior lobule. The lack of keloid history suggested the absence of genetic risk factors. The patient reported extensive mask-wearing habits that were augmented by the pandemic. The keloid developed from an ear injury. Although it healed well, it started thickening 2 months later. Because local mechanical forces (eg, pressure/ friction) can promote keloid growth, the ELFM may have provoked the keloid. The patient disclosed a history of uncontrolled hypertension and diabetes mellitus, which associate with severe keloids. The whole keloid was removed via total excision, and the defect was closed primarily and subjected to 15Gy/2Fr radiotherapy. The patient was advised to use a different mask type. Twelve months later, the scar had healed without complications or recurrence and with good cosmetic outcomes. Thus, ELFMs can promote retroauricular keloid formation, possibly by imposing local pressure/friction. ELFMs may also raise local skin temperatures and humidity, thereby fostering infection, which can trigger keloids. Hypertension/ diabetes may further elevate the risk of EFLM-induced keloid. Thus, an auricular keloid is an unusual complication of prolonged ELFM use. Combination therapy can have excellent outcomes. Patients with keloid risk factors should be advised to use face masks without ear loops.