Sebaceous cysts appear on the skin as small lumps or bumps just under the skin which move freely. They are generally painless and slow growing, however if they become infected they can become problematic causing inflammation and pain. Cysts are enclosed encapulations of wastes which contain sebum (oil) and keratin (dead skin cells and proteins). They may cause a discharge of a semi-solid pasty material and the smell omitted is generally cheesy and foul.
They are commonly caused as a result of swollen hair follicles or skin trauma. Sebaceous cysts most often disappear on their own and are not dangerous and complications arise if they become infected and cause abcesses . If the cyst is squeezed or irritated this may result in infection, pain, tenderness and inflammation. They are most commonly found around the facial area, neck, upper arms, ears, shoulders, back and occassionally the genital area, these are all areas which have hair growth.