RESUMEN
INTRODUCTION AND IMPORTANCE: Epidermoid cysts are generally seen as benign skin conditions characterized by the formation of nodules that are enclosed and located just beneath the epidermal layer. CASE PRESENTATION: This report presents the case of a 32-years-old woman with a mass that has been progressively growing for 11 years, situated at the right anal verge. The mass, which was asymptomatic throughout its development, was confirmed to be an epidermoid cyst. CLINICAL DISCUSSION: Epidermoid cysts commonly present without clinical symptoms. Ultrasound is increasingly being employed for the initial assessment. However, CT and MRI scans provide more detailed and specific imaging features. Histopathological analysis can aid in the identification of an epidermoid cyst. Treatment is often unnecessary for epidermoid cysts that are small and uncomplicated; however, if intervention is required, a complete surgical removal with an intact cyst wall is typically the straightforward solution. CONCLUSION: Epidermoid cysts are common and can manifest in various locations. When encountering a soft, well-defined mass in an atypical site for epidermoid cysts, it should be included in the differential diagnosis.