The scalp, like other parts of our skin, can sometimes suffer from abnormalities, such as the appearance of cysts. Although most of these formations are benign and harmless, it is natural to wonder about their nature and the possible dangers they represent. When these small lumps appear, how do you know whether they are simply the result of a clogged hair follicle or the sign of a more serious problem? Discover the causes of scalp cysts, the signs which should give you cause for concern and measures to be adopted when they appear. What's more, it's important to note that the presence of a cyst can sometimes be linked to a hair losswhich require a consultation at the Centre Clauderer, for example.
What is a scalp cyst?
A scalp cyst is a benign formation which develops under the skin, generally resulting from blockage of the sebaceous glands or hair follicles. Cysts may be filled with fluid, sebum or other materials, such as keratin, a protein present in the skin, hair and nails.
What are the different types of scalp cyst?
There are several types of cysts that can appear on the scalp. Here are the most common :
- Epidermal cyst (or sebaceous cyst): this is probably the most common type of cyst on the scalp. It results from an accumulation of keratin inside a cavity. Epidermal cysts form when epithelial cells, which normally migrate to the surface of the skin to be expelled, move deeper into the skin and multiply in an enclosed space. Over time, these cells produce keratin, the hard, whitish substance found in skin, nails and hair. It is this accumulation that creates the palpable, visible mass of the cyst.
- The pilar cyst (or trichilemmal): the hair cyst, also known as a trichilemmal cyst, originates in the hair follicle. Unlike the epidermal cyst, it is derived from the outer sheath of the hair follicle, which is the part responsible for hair growth. This specificity makes it particularly common on the scalp, although it can appear elsewhere on the body, in particular where hair density is high. Although the majority of pilaris cysts are harmless and benign, they may cause discomfort, particularly due to their size or location. In addition, like other types of cyst, they can become infected or inflamed, causing pain, redness and swelling.
- The dermoid cyst: this type of cyst is less common and generally forms during embryonic development. It may contain tissue such as skin, hair and sometimes teeth or bone. They are generally benign but may require surgery to remove.
- The inflammatory pilaris cyst: this is a variant of the hair cyst that becomes inflamed and can be painful. It is often caused by a rupture in the cyst, leading to inflammation in the surrounding tissue.
Scalp cyst: risk of cancer?
It's natural to be concerned about the appearance and nature of lumps or bumps on the scalp or elsewhere on the body, particularly when they appear suddenly or change over time. However, it is crucial to understand that the majority of scalp cysts are benign and are not associated with cancer.
Although most scalp cysts are harmless, it is advisable to consult a healthcare professional if there are any changes in size, shape or colour or if the cyst becomes painful, to ensure that they do not pose a risk to your health.
What are the symptoms of a cyst on the scalp?
A cyst on the scalp is generally a benign lesion that can go unnoticed for a long time, as it can be painless and unobtrusive. However, depending on its size, location and condition (for example, if it is inflamed or infected), certain symptoms may appear. Here are the most common symptoms associated with a scalp cyst:
- A palpable mass: the most obvious sign is a lump or mass on the scalp, often rounded, which may feel soft or firm to the touch.
- Movement under the skin: cysts are generally mobile under the skin when touched or pressed.
- Pain: although most cysts are painless, they can become painful if inflamed, irritated or infected.
- Redness or inflammation: if a cyst becomes infected or inflamed, the skin covering it may become red and warm to the touch.
- A flow: in some cases, a cyst may rupture and release its contents, which may be a thick, white or purulent substance if the cyst is infected.
- Itching : although less common, itching can sometimes accompany a scalp cyst.
- Rapid growth: some cysts, particularly pilaris cysts, may grow suddenly or continuously.
How is a cyst on the scalp diagnosed?
Diagnosis of a cyst on the scalp usually begins with a clinical assessment followed by other diagnostic procedures if necessary. The health professional observes the size, shape, colour and other visible features of the cyst.
The doctor will take into account the patient's family and medical history, as well as how long the cyst has been present and how it has developed. If the cyst shows unusual or worrying signs, the doctor may decide to perform a biopsy, i.e. take a sample of tissue for microscopic examination.
How do you treat a cyst on the scalp?
Treatment of a cyst on the scalp depends on its size, location, type and the presence or absence of associated symptoms (such as pain or infection):
- Careful monitoring: if the cyst is small, asymptomatic and does not look suspicious, the doctor may simply recommend monitoring it without immediate intervention, to ensure that it does not change in size or appearance.
- Surgical excision: this is the most common and effective method of treating scalp cysts. The dermatologist or surgeon surgically removes the cyst under local anaesthetic. This dermatological surgery generally prevents the cyst from recurring, as the entire cyst capsule is removed.
- Drainage: if the cyst is infected and forms an abscess, it may need to be drained. However, this method does not remove the cyst capsule, thus increasing the risk of recurrence. A complete scalp excision may be recommended at a later stage.
If the cyst is infected, antibiotics may be prescribed. Even though most scalp cysts are benign, it is always a good idea to have them assessed to rule out any potential concerns and ensure they are properly managed.