In the clinic, we often encounter patients who find some bulging lumps on their bodies, some of which look like a ball to the touch, and a black hole is often seen on the surface.
Squeezing hard can discharge some milky white bean curd-like semi-solid, smelling sour and unpleasant. This condition is most likely an epidermal cyst. (The first picture is a dermatoglyphic cyst on the back, the most common one occurring in this area. The second set of pictures shows an elderly woman with a cyst in her right groin that had grown for decades, the size of an egg, and underwent complete surgical removal) What is the difference between an epidermoid cyst and a sebaceous cyst? Some doctors are used to telling patients that this is a sebaceous cyst, which is not accurate. Sebaceous cysts mostly occur on the scalp and are also called hair cysts (below). And most of the ones we see growing on the body in clinical practice are epidermal cysts. Can epidermal cysts become malignant? What are the risks? Epidermal cysts are benign cysts that do not usually become malignant (very rarely they can become squamous cell carcinoma). However, its main risk is that it will continue to become infected and form an abscess. It is like a ticking time bomb. Once an infection occurs, the cyst can become red and swollen from its original size and increase in size several times. Untreated, it can form a larger abscess with significant pain. In this case, only an incision and drainage is performed in the hospital and the medication is changed. At first, the cyst needs to be cleared and drained every day, and it takes at least ten days to fully recover. The process of changing medication in between is rather painful. After the treatment, due to the large local trauma, it is also easy to form a very obvious scar that affects the appearance. What are the causes of epidermolysis bullosa? Where do they occur? Epidermal cysts can be primary, which means they occur naturally. It can also form as a result of trauma or acne that causes the epithelium of the hair follicle to implant into the dermis. It may remain unchanged for a long time or it may grow continuously. It can occur in any area. However, the best locations to develop are, the face, neck, chest and back, and buttocks. How are epidermal cysts treated? It is best to remove the cyst when there is no inflammatory redness and when the cyst is small. This is easy to remove cleanly and the surgical wound is not too large. Once the redness occurs, the outer wall of the cyst becomes very brittle and difficult to remove cleanly. There are two types of surgery: complete excision and microincision removal. For smaller cysts, it is best to remove the cyst directly and completely. In the patient pictured below, the dermatomal cyst on the left small lid, which had significantly affected the appearance, was repaired with cosmetic sutures after complete excision. Correspondingly, the larger the cyst, the more pronounced the scar left after excision. As in the patient below, who was operated on by me. If the cyst is relatively large and it is difficult to remove it directly, it is also possible to make small openings on the surface and squeeze out the contents, to remove the cyst wall as much as possible. However, this has a higher recurrence rate. To summarize, the risk of malignancy in dermatomal cysts is very low and may be almost negligible. However, secondary infection is a headache. Therefore, it is best to remove it early to eliminate future problems.