Cysts

Cysts

Cysts are a type of skin growth characterized by a sac-like structure containing fat, dead skin cells, hair, sweat glands, or other bodily secretions. These contents are housed within a cyst wall, which is composed of skin components such as hair follicles, fat gland ducts, or sweat gland ducts. Cysts can form as a result of blockage in these ducts, or from skin cells embedding themselves into the dermis layer after skin injury or during fetal development. Cysts formed due to the latter mechanism are present from birth.

There are several types of cysts, each with distinct characteristics based on their location and composition. Some cysts with walls similar to skin include Epidermal Cyst, Milium, Steatocystoma Multiplex, Vellus Hair Cyst, and Dermoid Cyst. Cysts that form from sweat gland ducts are classified as Apocrine and Eccrine Hidrocystoma.

Epidermal Cyst

The most common type of cyst, arising from hair follicle components in the skin. It contains keratin, a substance similar to nail clippings, within the cyst. These cysts can vary in size, have a round shape, and are the same color as the surrounding skin. They are attached to the skin surface but not the underlying tissues and may have an opening on the skin where they are attached. When the skin is stretched, a bump can be seen on the cyst, and white, paste-like contents may be squeezed out. However, this method should not be used for diagnosis, as it can cause inflammation, pain, and swelling. Epidermal Cysts can be found in individuals of any age, gender, or body part, but they are most commonly found on the face, neck, chest, and upper back.

Milium

Also known as "milk spots," these cysts have walls and components similar to Epidermal Cysts but are smaller in size. They appear as small, hard, white bumps resembling pimples, located just beneath the skin surface with a diameter of about 1-2 mm. These cysts can occur at any age, from newborns to the elderly, and affect both males and females equally. They can be found all over the body but are most common on the face, particularly on the nose in newborns and around the eyes and cheeks in children. Additionally, Milium often occurs in areas where the skin has been damaged previously, such as in regions with peeling skin, after facial scrubs, following radiation or sunburn exposure, or after certain skin diseases that cause clear fluid-filled blisters. It can also develop in areas treated with long-term topical steroid use. In most cases, milk spots may appear as the skin heals from various types of damage.

Steatocystoma Multiplex

This is a cyst that occurs in the sebaceous duct. The cyst wall is similar to that of an epidermal cyst, but the substance within the cyst is not keratin but fat produced by the sebaceous gland. This type of cyst is often found in teenagers and adults, both male and female. They appear as small bumps under the skin, varying in size but usually not exceeding 5 mm, and can be found on any part of the body. However, they are most commonly found on the chest, upper arms, and thighs. If the cyst is shallow, it appears as a yellowish bump; if it is deep, it appears as a bump the same color as the skin. A notable feature of this type of cyst is that when punctured, a yellow, butter-like oil flows out. These cysts often appear as multiple bumps at once.

Vellus Hair Cyst

This is a small cyst with a wall and contents similar to those of an epidermal cyst and steatocystoma multiplex. However, it also contains small vellus hairs. This makes the cyst appear as a dark bump. These cysts often appear as multiple bumps throughout the body.

Dermoid Cyst

This is a rare type of cyst, usually present from birth or during childhood. It is the cyst with the most skin-like composition. The cyst wall contains skin cells, hair, sweat glands, and sebaceous glands. The cyst appears as a round lump under the skin, about 1-4 cm in size, and may have hair protruding from it. Common locations for these cysts include the tail of the eyebrow, the nose, and the scalp. If the cyst is located in the midline of the body, such as the nose and the occipital region, it may have an opening connected to the brain.

Since the cyst wall consists of skin cells, there is a chance it can become cancerous, just like regular skin. However, the incidence of cancer from these cysts is very low, so there is no need to be overly worried. Complications from these cysts are usually due to inflammation and secondary infection, which often occurs when the cyst ruptures from being punctured or squeezed, or when it is in a position that experiences frequent friction. This causes the contents of the cyst to leak out and stimulate an inflammatory response in the body, allowing bacteria on the skin to penetrate and grow within the cyst, causing it to enlarge, become red, and painful. For dermoid cysts, in addition to the risk of inflammation and infection similar to other types of cysts, if the cyst has an opening connected to the brain, an infection in the cyst may spread to the brain, causing an abscess. Therefore, regardless of the type of cyst, one should avoid puncturing, scratching, or frequently touching the cyst, as this can lead to infection without realizing it.

Treatment

Since cysts have a low chance of becoming cancerous, there is no need to surgically remove them. However, cysts should be removed in cases where they are frequently inflamed or infected, or if they are in a location prone to friction. For small and superficial cysts, such as milia, treatment may involve puncturing and using a pimple extractor to remove the contents of the cyst. Other types of cysts can be treated by surgically removing the cyst mass. In the case of steatocystoma, since the contents of the cyst are oily, treatment may involve using a needle to drain the oil and peeling off the cyst wall. If a cyst is inflamed and infected, it needs to be treated with antibiotics along with incision and drainage to remove the pus. For dermoid cysts that are in a position that may be connected to the brain, a thorough examination along with a computed tomography scan is necessary, and precautions should be taken to prevent complications.

Cysts should not be a major concern as the chances of turning into cancer are very low. No matter what type of cyst you have or if you are unsure whether it is a cyst, it is advisable to see a dermatologist for diagnosis and peace of mind. The most important thing to take care of is to avoid squeezing or puncturing the cyst yourself, as this can lead to infection and scarring.

Best wishes from Obstetrics and Gynecology Center, Vibhavadi Hospital