Sebaceous cysts, commonly known as “pimples,” are cysts that form when sebaceous glands accumulate in the gland due to obstruction of the sebaceous ducts. This is one of the most common benign skin tumors, and many people have had the experience of having a cyst, especially young people in their prime growth spurt. Sebaceous cysts are most common on the scalp and face, followed by the trunk. Because of their varying depths and contents, they vary in size from small ones the size of a grain of rice to large ones the size of an egg. They are often diagnosed as lipomas, fibroids, etc. Sebaceous cysts grow very slowly, but patients can still feel that they are gradually increasing in size. Pink tumors are formed when the sebaceous glands of the skin are blocked and the secretions of the sebaceous glands cannot be drained and gradually expand. When a mass is formed, it is mostly located under the skin and half of it protrudes from the skin surface in a round shape. In the middle of the mass, there is often a black spot where the sebaceous glands are blocked. The whole mass can move with the skin, but not under the skin. This is what distinguishes it from other masses. Generally speaking, a mass appears on the body mostly by chance. It is often overlooked because it has no obvious symptoms. It is only when the mass grows or becomes painful that the patient pays attention to it and goes to the hospital. Sometimes the lump is infected, and a foul-smelling discharge may come out, or something like a grayish-white powder may be squeezed out. If there is pus flow, you need to go to the hospital for treatment, drainage, drug changes, anti-inflammatory, etc., to toss a long time.