What is the cause of a hard bump on the face

There are several possibilities for a hard pack on the face: 1, dermatofibroma: the boundaries are clear and brown, and the texture is hard. The treatment requires surgical excision and histopathological examination of the skin in order to clearly diagnose the disease. 2, seborrheic keratosis: the cause is not clear, and may be related to sunlight and other factors, light brown or dark brown patches, the surface is slightly rough. It can be treated by carbon dioxide laser cautery, or surgical excision. 3, acne: the appearance of a nodular rash performance. Treatment can be applied to the treatment of fire needle acupuncture, to achieve the purpose of clearing heat and detoxification, activating blood circulation and removing blood stasis.