A cyst is a sac-like structure that develops in the body, typically filled with fluid, air, or semi-solid material. The relationship between a cyst and hair loss depends entirely on the cyst’s nature and location. The connection follows two pathways: one involves internal chemistry causing widespread thinning, and the other involves physical growth causing localized hair loss. Understanding this difference helps guide appropriate consultation with a health professional.
Internal Cysts Causing Systemic Thinning
The most common internal cause of cyst-related hair loss originates with Polycystic Ovary Syndrome (PCOS). This endocrine condition involves a hormonal imbalance where ovarian cysts contribute to the overproduction of androgens, such as testosterone and dihydrotestosterone (DHT). These cysts are typically small, fluid-filled sacs that form when an egg fails to mature and release during the menstrual cycle. The presence of these multiple follicles influences the hormonal environment and hair health.
The elevated levels of androgens act directly on genetically susceptible hair follicles across the scalp. This hormonal exposure triggers a process known as miniaturization, where the hair follicle gradually shrinks over successive growth cycles. The hair produced becomes progressively shorter, finer, and lighter in color until the follicle eventually becomes inactive. This process results in a type of hair loss known as androgenic alopecia, or female pattern hair loss.
This systemic process presents as diffuse thinning across the entire scalp, rarely causing sudden bald patches. The characteristic pattern often involves a noticeable widening of the part line, particularly near the crown and frontal area. This thinning is a chronic condition that progresses slowly due to the ongoing disruption of the hair growth cycle. The hormonal shifts that cause scalp hair to thin can sometimes lead to excessive hair growth on the face or body.
Scalp Cysts Causing Localized Hair Loss
A second connection involves growths that develop directly on the scalp. These are typically benign skin cysts, such as pilar or epidermoid cysts, originating from the hair follicle or skin cells. Pilar cysts, also called trichilemmal cysts, are filled with keratin and frequently appear on the scalp as firm, mobile lumps beneath the skin. Hair loss here is not due to hormonal changes but is a direct result of physical and inflammatory mechanisms.
The primary mechanism for localized hair loss is the physical mass of the cyst itself, which can displace or compress surrounding hair follicles. If the cyst grows large enough, the sustained pressure can disrupt the follicle’s ability to anchor the hair shaft and sustain the growth phase. This can result in a localized, non-scarring patch of hair loss directly over the growth.
A more serious cause occurs if a scalp cyst becomes inflamed, infected, or ruptures. Such events trigger a significant inflammatory response in the surrounding tissue. If the inflammation is severe and prolonged, it may destroy the hair follicle stem cells, leading to scar tissue formation. This destruction of the hair follicle and replacement by scar tissue is known as cicatricial alopecia, which results in permanent baldness in that specific patch.
Determining the Specific Cyst Connection
Differentiating between systemic and localized cyst-related hair loss requires a thorough clinical evaluation by a healthcare provider. The physical examination of the scalp is the first step, as the pattern of hair loss provides a strong initial clue. Diffuse thinning with a preserved frontal hairline usually points toward a hormonal or systemic cause like PCOS, while a distinct, circular bald patch directly over a palpable mass suggests a localized scalp cyst.
If a hormonal cause is suspected, a blood test panel is often ordered to measure levels of androgens, such as total and free testosterone, and dehydroepiandrosterone sulfate (DHEA-S). Elevated levels of these hormones can confirm hyperandrogenism, which is a hallmark of PCOS. The healthcare provider may also check other related markers, including thyroid function, iron stores, and sometimes an insulin screen, to rule out other common causes of hair thinning.
For suspected internal cysts, an ultrasound examination may be used to visualize the ovaries and confirm the presence of the multiple small follicles characteristic of polycystic ovarian morphology. Conversely, for a localized scalp mass, diagnosis often relies on the physical characteristics and location of the lesion. In cases where the diagnosis is unclear or scarring is present, a small scalp biopsy may be necessary to examine the tissue under a microscope and determine if the hair follicles have been destroyed.
Resolving Hair Loss Through Cyst Treatment
Treatment for cyst-related hair loss addresses the underlying cause, whether it is an internal hormonal imbalance or a physical mass on the scalp. For systemic hair loss linked to PCOS, the goal is to reduce the androgen’s influence on the hair follicles. This is commonly achieved through hormonal therapies, such as oral contraceptive pills, which help regulate the menstrual cycle and increase sex hormone-binding globulin, thereby lowering free testosterone.
Medications known as anti-androgens, such as Spironolactone, are also frequently prescribed to block the effects of androgens on the hair follicle, which can slow the progression of thinning and sometimes promote hair regrowth. Addressing insulin resistance, which often accompanies PCOS, through lifestyle changes or medication like Metformin, can also indirectly help moderate androgen levels. These treatments require consistency and patience, as noticeable hair density improvements can take six months or longer.
For hair loss caused by a localized scalp cyst, the primary treatment is surgical removal or drainage of the growth. Common pilar and epidermoid cysts are typically removed through excision, a minor surgical procedure that removes the entire cyst wall to prevent recurrence. If the cyst caused hair loss through temporary pressure or inflammation, hair regrowth usually begins within a few months after removal. However, if the cyst caused significant infection or rupture leading to permanent scarring, the hair loss in that specific area may be irreversible because the hair follicles have been destroyed.