A pilar cyst grows from the outer root sheath of a hair follicle, sits on the scalp in roughly 90% of cases, feels firm to the touch, and has no visible pore. A sebaceous cyst — which in almost every case is really an epidermoid cyst — grows from surface skin cells, can appear anywhere on the body, feels softer, and usually has a small dark central opening called a punctum that releases foul-smelling material if squeezed. Neither is cancerous. Both can become infected, and both are treated the same way: by removing the cyst together with its wall.
Pilar cysts develop from hair follicle tissue and concentrate on the scalp, while epidermoid cysts can form anywhere and favour the face, neck, chest and upper back. The contents differ enough to be a useful clue, with pilar cysts holding dense compact keratin that barely smells and epidermoid cysts holding a softer keratin and lipid mixture that smells strongly when it ruptures. Pilar cysts run in families through an autosomal dominant pattern linked to the PLCD1 gene on chromosome 3, whereas most epidermoid cysts are sporadic and follow blockage or trauma rather than inheritance.
The term sebaceous cyst is a long-standing misnomer, since genuine sebaceous gland cysts are rare and belong to a separate condition called steatocystoma. Pilar cysts affect women more often than men and typically appear between the ages of twenty and sixty, while epidermoid cysts affect both sexes roughly equally and peak between puberty and around forty. Neither type is contagious.
Both respond well to complete surgical excision, with published recurrence rates of under four percent when the entire cyst wall comes out, and incomplete removal of that wall is the single most common reason a cyst returns. Malignant transformation is rare for both, though rapid growth, new pain, or a lump that becomes fixed to the tissue beneath it should be assessed promptly. Squeezing or popping either type at home is a bad idea, because it raises infection risk while leaving the wall behind, which guarantees the cyst refills.
The distinction comes down to five things: where they form, what tissue they originate from, what they contain, whether they smell, and whether genetics is involved.
Pilar cysts form on the scalp about 90% of the time, arising from the outer root sheath of a hair follicle, and they fill with dense compact keratin. They rarely have a central opening, they produce little odour, and they show a strong hereditary tendency. They are more common in women, by a ratio usually cited somewhere between two and four to one, and people who get them often get several rather than just one. Their walls lack a granular layer, and they calcify comparatively often, which is why an old pilar cyst can feel surprisingly hard.
Epidermoid cysts, by contrast, turn up on the face, neck, trunk, back and genitals, arising from the epidermis or from the infundibulum of a hair follicle. They fill with a softer, cheese-like mixture of keratin and lipid, they frequently show a visible punctum at the surface, and they smell distinctly foul when that material is released. They are usually solitary or few in number, they affect men and women roughly equally, and hereditary cases are confined to rare syndromes. Their walls do contain a granular layer, and they calcify less often than pilar cysts do.
At the microscopic level the distinction becomes definitive rather than probabilistic. Pilar cysts are lined with epithelium resembling the outer root sheath and undergo trichilemmal keratinisation, producing dense homogeneous keratin with no granular cell layer. Epidermoid cysts are lined with stratified squamous epithelium that mirrors normal skin, do produce a granular layer, and yield laminated softer keratin mixed with lipid debris. This is why pathology after excision is the only fully reliable way to name a cyst, and why we send every specimen for examination.
If you want a broader view of how these two fit within the full range of skin growths, our guide to 25 types of skin lesions and our overview of 17 types of cysts set out the wider landscape.
Location is the single most reliable first clue. A smooth, firm, mobile lump on the scalp is a pilar cyst until proven otherwise. A similar lump on the face, neck, chest or back with a small dark central opening is far more consistent with an epidermoid cyst.
Beyond location, four other features point toward a pilar cyst. It tends to feel firm, almost hard, rather than doughy. It has no visible central pore. There is often more than one, sometimes five or ten scattered across the scalp. And a parent, sibling or child has frequently had the same thing removed. If a pilar cyst becomes irritated it still produces little or no odour, which distinguishes it further.
Five features point the other way, toward an epidermoid cyst. It sits on the face, neck, chest, upper back or groin rather than the scalp. It feels soft to moderately firm with a slightly doughy give. There is a visible small dark dot at the surface. There is often a history of acne in the same area. And if it is squeezed or ruptures, the discharge smells strongly and unmistakably foul. It also tends to be a single isolated lump rather than one of a cluster.
The most common self-assessment error is assuming that any scalp lump must be a sebaceous cyst, when on the scalp pilar cysts are considerably more common. The reverse mistake happens too, with people assuming a firm neck lump is a pilar cyst when it is more likely an epidermoid cyst or a lymph node. In practice a clinician can usually separate the two on physical examination alone, assessing size, consistency, mobility, tenderness and the presence or absence of a punctum. Imaging or biopsy is rarely needed for a straightforward presentation. If the cyst has been removed before, the pathology report from that excision is the most definitive record of which type it was.
Our guide to the types of scalp cysts goes into more detail if the lump in question is on your head.
The term implies the lump is filled with sebum from an oil gland, and almost none of them are. What people call a sebaceous cyst is nearly always an epidermoid cyst: a sac lined with skin cells, filled with the keratin those cells shed as they mature.
True sebaceous cysts do exist, but they belong to a separate and much rarer condition called steatocystoma, which genuinely does contain oily sebum. If you have dozens of small, soft, oil-filled bumps across your chest, arms or underarms, the diagnosis worth reading about is steatocystoma multiplex, which follows a different course and a different treatment plan entirely.
The old label persists because it has been in patient-facing use for more than a century and because it is what almost everyone searches for. Clinically nothing hinges on it, which is why our sebaceous cyst removal page uses the familiar term while describing the correct procedure.
Pilar cysts form when cells from the outer root sheath of a hair follicle proliferate abnormally and create a closed sac that fills with keratin. Unlike epidermoid cysts, which are often triggered by something external, pilar cysts are primarily driven by genetics.
The genetics deserve a proper correction, because a claim repeated across most articles online has no traceable source. You will frequently read that 70% of people with pilar cysts have a family history, but that figure appears to have been copied from site to site without attribution to any study. The real evidence is both better and more interesting.
Leppard and Sanderson first described autosomal dominant inheritance in 1976, and in their follow-up series of 115 individuals drawn from 60 families, autosomal dominant inheritance was demonstrated in 46 of those 60 families. Then, between 2019 and 2020, researchers identified the mechanism itself. Every one of 21 pilar cysts studied carried a somatic PLCD1 p.S745L mutation, and 16 of the 17 people with multiple cysts also carried a germline PLCD1 p.S460L variant, as reported in Scientific Reports. PLCD1 sits on chromosome 3 and functions as a proposed tumour suppressor. Unusually, both mutations were found on the same chromosome copy rather than on opposite alleles, which contradicts the classic two-hit model and helps explain why the condition behaves as a dominant trait.
The finding most useful to patients is this: roughly one third of apparently sporadic pilar cysts turn out to be familial with incomplete penetrance. A great many people who are confident nobody in their family has them do in fact carry a genetic predisposition. Where a parent carries the relevant variant, each child has approximately a 50% chance of inheriting it.
Beyond genetics, follicle density explains geography. The scalp carries a very high concentration of hair follicles, which is why pilar cysts concentrate there. Age and hormonal factors play some part, given that these cysts appear most often between twenty and sixty and affect women more often than men, though the mechanism behind the sex difference is not settled. Repeated mechanical irritation from tight hairstyles, helmets or habitual scratching may contribute at the margins, but this is far less well established than the genetic driver.
What does not cause pilar cysts is worth stating plainly. They do not come from poor hygiene, diet, or any contagious exposure. No virus or bacterium is responsible. Where a genetic predisposition exists, no lifestyle change reliably prevents them.
Epidermoid cysts are not contagious. They cannot be passed on through skin contact, shared towels, razors or any other form of exposure. They are also not hereditary in the ordinary sense, although a few rare genetic syndromes do cause multiple epidermoid cysts to develop.
Most arise from a blocked hair follicle, where an obstructed opening traps skin cells that would normally shed, allowing them to accumulate into a sac. Skin trauma is the next most common route, with cuts, surgical incisions, acne lesions and puncture wounds all capable of driving surface skin cells deeper into the dermis, where they continue dividing. Certain strains of human papillomavirus have been associated with epidermoid cyst formation in some individuals, particularly in palmoplantar cases, though this is far from a universal cause. A history of moderate to severe acne raises the risk, most likely because acne-related inflammation disrupts follicular architecture.
Genetic syndromes account for a small but clinically important minority. Gardner syndrome, which involves mutations in the APC gene, and Gorlin syndrome are both associated with multiple epidermoid cysts alongside other features. Gardner syndrome in particular matters, because multiple epidermoid cysts appearing in a child or teenager, especially with a family history of bowel cancer, warrants a gastroenterology referral rather than simply removing the cysts. These presentations are distinct from ordinary sporadic cysts and need specialist management.
The contrast with pilar cysts is instructive. Where pilar cysts are inherited and follow families through generations, most epidermoid cysts are sporadic, occurring without any family pattern and tied far more closely to environmental or mechanical triggers.
Pilar cysts are by a wide margin the more common scalp cyst. Around 90% of all pilar cysts occur on the scalp, and they represent the most common cutaneous cyst found there, according to Medscape. Epidermoid cysts can certainly appear on the scalp, but they turn up there far less often than on the face, neck and trunk.
If someone has several lumps on the scalp, the probability that they are pilar cysts is very high, and a family history pushes that probability higher still. A single scalp lump with no family history could be either type, and clinical examination or excision with pathology remains the reliable way to confirm.
Calcification offers one more clue. Pilar cysts calcify more readily than epidermoid cysts, which can make an older one feel unusually hard. A hard, long-standing lump on the scalp that has been present for years is almost certainly a pilar cyst.
No, and the difference is a genuinely useful diagnostic clue. Pilar cysts produce little or no odour, while epidermoid cysts are well known for a distinctly foul smell when they rupture or are squeezed.
The reason lies in the contents. Pilar cysts hold dense, compact keratin with a homogeneous paste-like consistency, and that material has minimal odour because it lacks the lipid component responsible for the smell. Epidermoid cysts contain a mixture of keratin debris and lipids, sometimes including cholesterol crystals, and when that material meets air and bacteria it breaks down into volatile fatty acids. The result is the cheesy, rancid smell that most people who have encountered it describe as unmistakable.
This matters practically when a cyst ruptures or drains on its own. A scalp lump producing foul-smelling discharge is more likely to be an epidermoid cyst than a pilar cyst, even though the scalp is so strongly associated with pilar cysts. Odour alone should never carry a diagnosis, but alongside location, consistency and family history it is a genuinely informative data point.
Pilar cysts are significantly more common in women than in men, with clinical estimates putting the ratio somewhere between two and four to one, though the exact figure varies across studies. The reason for this difference is not fully established, but hormonal influences on hair follicle biology are the most likely explanation.
By age, they appear most commonly in adults between twenty and sixty. They are uncommon in children and adolescents, which distinguishes them from several other cyst types that can appear earlier in life. They occur across all ethnic backgrounds with no clearly established predisposition.
The strongest single predictor remains family history. Someone with a parent or sibling who has had pilar cysts carries a meaningfully elevated risk, and in some families multiple members across two or three generations will have had scalp cysts removed.
People who develop pilar cysts frequently develop several rather than one. Having five, ten or more scattered across the scalp at the same time is not unusual, and this multiplicity is itself one of the more reliable pointers toward the diagnosis.
Newer research has started to describe how these cysts behave over time. A retrospective study of 27 patients at a tertiary plastic surgery centre, published in 2025, found that patients with multiple lesions were older, with a median age of 54 against 38.5, and had substantially larger cysts, with a median size of 30 mm against 9 mm. Age and diabetes mellitus independently predicted larger lesions, while histological infection trended toward association with diabetes and hypertension. No association emerged with smoking, Fitzpatrick skin type or headscarf use. The sample is small, so this is a signal rather than settled fact, but it supports something surgeons observe routinely: waiting makes the operation bigger, and metabolic health appears to matter more than most patients assume.
No. A pilar cyst cannot transform into an epidermoid cyst. They are distinct entities with different cellular origins, and one does not convert into the other. The confusion arises because both get called sebaceous cysts in everyday language, which makes them sound like the same thing at different stages.
What can happen is a change within the pilar cyst itself. Around 3% of trichilemmal cysts become proliferating trichilemmal tumours, according to the Cleveland Clinic. This is not a conversion into a sebaceous cyst but a variant of the pilar cyst showing more active cell growth. These grow quickly rather than slowly, can exceed five centimetres, can ulcerate, and can behave in a locally aggressive way. They require complete surgical excision and always go for pathological examination.
Malignant transformation of an ordinary pilar cyst into trichilemmal carcinoma is genuinely rare, typically associated with long-standing large cysts or prior trauma to the area. The practical takeaway is about pattern rather than probability: if a known pilar cyst starts growing rapidly, becomes fixed to underlying tissue, or changes texture, get it evaluated. A stable pilar cyst that has looked the same for years does not warrant urgent concern.
If the lesion is crusted, bleeding or failing to heal rather than smooth and dome-shaped, the relevant reading is our guide to skin cancer on the scalp, because that pattern points somewhere different.
Many epidermoid cysts stay stable for years or even decades without causing any problem, and leaving a small asymptomatic one alone is a perfectly reasonable choice. Clinical practice generally supports watchful waiting for cysts that are not growing, not infected and not cosmetically bothersome.
That said, several risks accumulate over time. Infection is the most common, where the cyst contents become colonised by bacteria and develop into a painful abscess, announced by redness, warmth, swelling, tenderness and pus. An infected cyst usually needs drainage and antibiotics, and often cannot be cleanly excised until the infection has settled.
Rupture is the next concern. The wall can give way spontaneously or after minor trauma, releasing contents into the surrounding tissue and triggering an inflammatory response that is frequently more painful than the cyst ever was, and which can leave scarring behind.
Gradual enlargement is slower but no less real. A cyst measuring one centimetre today may reach three or four over several years, which makes eventual removal a more involved procedure with a longer scar. Cysts that rupture and reform repeatedly develop surrounding scar tissue that complicates clean surgical removal and raises the recurrence risk when they finally do come out.
Cosmetic considerations tend to be what tips the decision. A cyst on the face, neck or chest becomes more visible as it grows, and the scarring left by repeated episodes of inflammation is often more disfiguring than a planned surgical excision would have been. That asymmetry is the strongest practical argument for elective removal while a cyst is small.
For anyone weighing this up locally, our Mississauga cyst removal clinic offers consultations for both pilar and epidermoid cysts.
No. Attempting to pop, squeeze or drain a pilar cyst at home is unsafe and is not recommended by any clinical guideline. The same applies to epidermoid cysts.
The core reason is that squeezing does not remove the cyst wall. That wall is the sac lining, and it is what produces the keratin contents in the first place. Expressing the contents while leaving the wall in place guarantees the cyst refills, usually within weeks to months. The only way to prevent that is to excise the entire wall intact.
Infection risk is the second reason. Breaking the skin over a cyst without sterile technique creates a direct route for bacteria, and pilar cysts on the scalp are particularly vulnerable because hair harbours bacteria. An infected pilar cyst is considerably more painful and harder to treat than an intact one.
There is also a specific hazard people underestimate. Aggressive squeezing can rupture the cyst wall internally rather than through the skin, releasing keratin into the surrounding dermis. This sets off a foreign-body inflammatory reaction that is painful, produces significant swelling, and can leave permanent scarring. It is frequently mistaken for infection, which is why antibiotics so often disappoint in this situation — the problem is sterile inflammation, not bacteria.
Finally, many older pilar cysts contain calcified deposits that simply cannot be expressed through the skin no matter how much pressure is applied.
The correct approach for a bothersome pilar cyst is surgical excision by a qualified provider, typically under local anaesthetic, taking fifteen to thirty minutes, and removing the wall completely. Options across the region include our Barrie cyst removal clinic and locations throughout the GTA.
Costs are broadly comparable for the two types, because the surgical technique is essentially the same. What actually moves the price is cyst size, location, whether the cyst is infected, and whether the procedure happens in the public system, a private clinic or a hospital.
OHIP generally does not cover removal of a cyst that is purely cosmetic. Coverage becomes possible when the cyst is symptomatic, meaning infected, recurrently inflamed, painful, bleeding, rapidly enlarging or interfering with function. That determination is clinical and typically requires a family physician referral, and the trade-off is waiting time, with multi-week to multi-month waits being common.
Privately, cyst removal at a minor surgery clinic in the Greater Toronto Area generally runs from a few hundred dollars for a small simple lesion up to well over a thousand for large, multiple or complex cysts. Pathological examination of the excised tissue may add a separate laboratory fee. Several factors push the price upward: cysts larger than about three centimetres that need wider excision, infected cysts requiring drainage and a staged removal, cysts in cosmetically sensitive areas like the face or the hairline where closure technique is more demanding, calcified pilar cysts that are harder to remove intact, and cysts surrounded by scar tissue from earlier ruptures. Working the other way, small superficial cysts with intact walls sit at the lower end, several cysts removed in one session often attract reduced per-unit pricing, and cysts that qualify as medically necessary may be covered outright.
The cost difference between removing a pilar cyst and an epidermoid cyst of the same size is generally minimal. The approach is the same in both cases: local anaesthetic, incision, dissection of the wall, closure. Pilar cysts on the scalp may call for a slightly different closure technique because the skin is hair-bearing, but that rarely changes the price meaningfully.
For current figures and a fuller breakdown, our 2026 guide to cyst removal cost in Ontario works through the variables, and our pricing page lists what we charge.
Recovery timelines are broadly similar for both cyst types, and most people return to normal daily activities within twenty-four to forty-eight hours of a straightforward excision.
The first three days bring mild soreness, some swelling and occasional bruising around the incision, and over-the-counter acetaminophen or ibuprofen is usually enough. Between days three and seven the swelling subsides, and non-absorbable sutures come out somewhere between seven and fourteen days depending on the site, with the face at the earlier end and the scalp, back and trunk at the later end. Across weeks two to four the incision continues healing and a small scar forms. Most excision sites are fully healed within four to six weeks, though scar maturation continues quietly for up to a year.
Scalp surgery has its own character. Scalp wounds heal well thanks to a rich blood supply, but that same blood supply means more bleeding during and immediately after the procedure than you would see on the trunk or limbs. Patients are typically advised to avoid vigorous hair washing for forty-eight hours, to skip strenuous exercise for five to seven days, and to keep the area dry until sutures come out.
Several things extend recovery: cysts that were infected and needed drainage before excision, large cysts requiring wider incisions, cysts surrounded by scar tissue from previous ruptures, and calcified pilar cysts that need more dissection to free.
Recovery from an epidermoid cyst removal on the face or neck may involve slightly more visible bruising or swelling in the first week, simply because the tissue there is thinner and more vascular, but the functional timeline is the same.
The scar itself follows a predictable arc. It stays firm and pink for the first couple of months, which is normal and not a sign anything has gone wrong, then softens and fades across the following three to twelve months. Daily sunscreen on the scar for at least six months makes a genuine difference to the final appearance, and it is the easiest thing a patient can do to improve their own result. If an older removal left a mark you dislike, our scar revision guide covers what can be done about it.
Call the clinic if you notice spreading redness, pain that increases rather than decreases after day three, pus, a fever above 38 °C, or wound edges beginning to separate.
Yes, but the risk is low when the procedure is done properly. The determining factor is whether the entire cyst wall came out intact. If any part of the wall is left behind, the remaining cells regenerate the cyst.
The published evidence here is more precise than the figures usually quoted online. A prospective randomised trial comparing minimal excision with traditional elliptical excision for epidermal inclusion cysts recorded recurrence rates of 2.8% and 3.3% respectively, a difference that was not statistically significant, while minimal excision produced shorter wounds averaging 2.3 cm and roughly half the operative time, at 6.4 minutes against 11.3. Punch excision sits somewhat higher at around 6%. Incision and drainage alone performs worst of all, because it empties the cyst while leaving the wall exactly where it was. A 2026 systematic review in Cureus reached the same conclusion at a higher level of evidence, finding that complete excision consistently beats incision and drainage on recurrence, while minimally invasive and CO₂ laser-assisted approaches deliver good cosmetic outcomes with acceptable recurrence.
What this means practically is that a smaller incision is not a worse operation, provided the surgeon removes the whole capsule. The question worth asking in consultation is about capsule removal, not about incision length.
Beyond incomplete excision, two other things produce what looks like recurrence. Cyst rupture during surgery spills contents into the wound, and although thorough irrigation reduces the risk, residual wall fragments can regrow. And entirely new cysts can form at different follicles elsewhere on the scalp, which is not a recurrence of the original at all but a fresh growth driven by the same underlying genetics. Anyone with a strong family history should understand that successfully removing existing cysts does not stop new ones appearing, and periodic monitoring is sensible.
Pilar cysts do not typically resolve on their own. Unlike inflammatory skin conditions that fluctuate with the immune response, a pilar cyst is a structural growth with a defined wall that keeps producing keratin. Left alone it persists indefinitely and often enlarges slowly across years.
Removal is generally recommended when the cyst is cosmetically bothersome or visible, when it causes pain, tenderness or pressure — particularly under helmets, hats or tight hairstyles — when it has become infected or inflamed, when it is growing noticeably, when it has ruptured or drained more than once, or simply when the patient wants it gone for peace of mind. That last reason is entirely legitimate and needs no medical justification.
Watchful waiting is reasonable when the cyst is small, under about a centimetre, stable and causing no symptoms, when it sits somewhere that does not get irritated, when the patient is not bothered by it, and when there is no sign of infection or rapid growth.
There is no medical urgency to remove a stable, asymptomatic pilar cyst. But there is a practical argument for acting sooner rather than later: elective removal while the cyst is small and uncomplicated is technically easier, heals faster, and leaves a smaller scar than removal after repeated infections or years of enlargement. The 2025 data showing that older patients present with substantially larger lesions reinforces the point.
The same general principle applies to epidermoid cysts. A stable, small one can be monitored. A growing, infected or repeatedly inflamed one is better managed by excision. Our step-by-step guide to pilar cyst removal covers what the procedure involves, and pilar cysts on the scalp covers appearance and progression in more detail.
In most cases a clinician diagnoses both types on physical examination alone, with no blood tests, scans or biopsies required.
The examination covers visual inspection of location, size, shape, colour and the presence or absence of a punctum, followed by palpation to assess consistency, mobility, tenderness and whether the lump is attached to deeper structures. History matters too: when the lump appeared, how quickly it has grown, whether family members have had similar lumps, and what has already been tried.
Additional testing has a narrow role. Ultrasound is occasionally ordered for large or deep cysts, to confirm the lesion is fluid-filled and to map its relationship to surrounding structures before surgery. For epidermoid cysts it carries a reported sensitivity of about 80% and specificity of about 95%, showing a well-circumscribed avascular mass with posterior acoustic enhancement, according to the European Journal of Radiology Open30040-1/fulltext). CT and MRI are rarely needed for simple cysts but come into play for very large scalp lesions or where there is any question of erosion into underlying bone. Fine needle aspiration is generally not recommended, because it leaves the wall behind, carries a high recurrence rate, and adds little diagnostic value when the clinical picture is already clear.
Pathology after excision is the gold standard, and it is the only way to confirm a pilar cyst versus an epidermoid cyst with complete certainty. The pathologist looks above all for the granular layer: present means epidermoid, absent alongside dense laminated keratin means trichilemmal. The examination also rules out atypical or malignant cells and identifies secondary changes such as calcification or infection.
Anyone with a skin lesion that does not fit a clear clinical picture, grows rapidly, or shows irregular features should be evaluated promptly rather than monitored. Our skin cancer screening service in Toronto and our comparison of skin cancer screening options across the city cover what that assessment involves.
Surgical excision is the standard treatment for both, with only minor variations based on location and cyst characteristics.
The procedure runs as follows. The area is cleaned and local anaesthetic is injected around the cyst. A small incision is made over it, sized to allow the intact sac to come out. The wall is then dissected free from the surrounding tissue, ideally without rupturing it. The intact cyst is removed and the wound irrigated. The incision is closed with sutures, removed at seven to fourteen days, or with absorbable sutures in some locations. The excised cyst goes to pathology for confirmation. The whole thing typically takes fifteen to thirty minutes under local anaesthetic in an outpatient setting.
Scalp surgery for pilar cysts carries a few specific considerations. The rich blood supply means faster healing but brisker bleeding, so careful haemostasis matters. Only a small area of hair usually needs trimming, and it is generally invisible once surrounding hair falls back into place, so full head shaving is rarely necessary. Multiple cysts can often be removed in one session through separate small incisions, and larger or calcified cysts may need a layered closure.
Face and neck surgery for epidermoid cysts is planned differently. Incisions follow relaxed skin tension lines to minimise visible scarring, and the punctum is usually excised with a small ellipse, since it is continuous with the cyst wall and leaving it behind invites recurrence. Fine sutures removed early, at around five to seven days on the face, give the best cosmetic result.
An actively infected cyst is not excised immediately. The standard sequence is incision and drainage first, opening the cyst and allowing it to drain and heal, with antibiotics prescribed where there is surrounding cellulitis or systemic signs of infection. Definitive excision of the wall follows once the infection has fully resolved, typically four to six weeks later. Attempting to excise an infected cyst during the acute phase raises the risk of incomplete removal, wound breakdown and spreading infection, and it produces a worse scar.
Small asymptomatic cysts that are neither growing nor causing problems can simply be monitored. Patients choosing that route should avoid squeezing the cyst, protect it from trauma, and report any change in size, pain or appearance.
It is worth being direct about what does not work. Topical creams, essential oils and over-the-counter preparations do not dissolve cyst walls or eliminate cysts, because nothing applied to the skin surface reaches an intact capsule. Warm compresses can ease the discomfort of an inflamed cyst without curing it. Steroid injections can temporarily reduce inflammation in an irritated cyst but do not remove it. These have a place in managing acute inflammation and no place as a cure.
If you are weighing up who should perform the procedure, our comparison of a plastic surgeon versus a dermatologist for cyst removal sets out the trade-offs, and you can read about our surgical team and their credentials.
Not every lump under the skin is a cyst, and several look-alikes are worth ruling out before assuming.
A lipoma feels soft and doughy, sits deeper in the tissue, has no punctum and does not become infected. It is a benign fatty tumour rather than a keratin-filled sac, which makes it an entirely different tissue type despite the superficial resemblance. Our guide to lipoma clinics in Toronto covers lipoma-specific considerations.
An abscess develops over days rather than years and is hot, exquisitely tender and often accompanied by fever, which separates it fairly reliably from a cyst that has been sitting quietly for months. A dermatofibroma is firm and dimples inward when pinched, usually appearing on the leg. A pilomatricoma feels hard and chalky, appears most often in children and young adults, and favours the face and arms. A dermoid cyst is present from birth or early childhood, typically near the eyebrow or on the midline. A ganglion cyst sits near a joint or tendon, contains clear jelly, and may fluctuate in size from week to week.
Skin cancer is the diagnosis nobody wants to miss, and it announces itself differently from any cyst: crusting, bleeding, failure to heal, a change in colour, or an irregular border. Any of those features warrants prompt assessment rather than watchful waiting, and our skin cancer treatment page explains what happens next.
Neither pilar nor epidermoid cysts are cancer, and the overwhelming majority never become cancer.
For pilar cysts, about 3% become proliferating trichilemmal tumours, which are usually benign but locally aggressive, and frank malignant transformation to trichilemmal carcinoma is rarer still. For epidermoid cysts, reported rates of transformation to squamous cell carcinoma vary widely across the literature, from around 0.01% in large population series up to about 1% in selected surgical cohorts. That wide range reflects selection bias rather than genuine disagreement, since surgical series inevitably over-represent unusual cysts that were removed precisely because something looked odd.
What matters more than the percentage is the pattern behind it. Long-standing, large, repeatedly inflamed cysts in older patients account for most reported cases. That is a strong argument for removing a cyst that keeps flaring rather than living with it for twenty years, and an equally strong argument for sending every specimen to pathology rather than assuming a benign result.
The first is that sebaceous cysts are full of oil. Almost never; they contain keratin, and the genuinely oil-filled version is a steatocystoma, which is a different condition.
The second is that you can squeeze one out and be done with it. Squeezing empties the contents but leaves the wall, which refills. It also risks rupture into the dermis, inflammation, infection, and a worse scar than surgery would have left.
The third is that cysts come from poor hygiene. They do not. Pilar cysts are genetic, epidermoid cysts follow follicular blockage or trauma, and washing more prevents neither.
The fourth is that home remedies dissolve cysts. Nothing applied topically reaches or removes an intact cyst wall.
The fifth is that antibiotics will fix an inflamed cyst. Often the inflammation is a sterile foreign-body reaction to leaked keratin rather than a bacterial infection, so antibiotics help when there is genuine infection and do very little otherwise.
One more is worth adding: pilar cysts are not confined to older people. They typically present between twenty and sixty, and the 2025 series described earlier included patients as young as seventeen.
Get the lump assessed if it is growing noticeably faster than it used to, if it has become painful, red or hot, if it has ruptured or is discharging, if it bleeds or crusts or fails to heal, if it feels fixed to deeper tissue rather than moving freely, or if it is one of several new lumps that have appeared over a short period.
It is also entirely reasonable to have a cyst removed simply because it bothers you, catches on a comb, rubs against a collar or gets nicked by a razor. Cosmetic concern is a legitimate reason for treatment, and you do not need to justify it medically.
Is a pilar cyst the same as a sebaceous cyst? No. They are different types of benign skin growth, differing in cellular origin, location, contents, odour and genetics. The term sebaceous cyst gets used as a catch-all in everyday language, which is where most of the confusion comes from.
Can a pilar cyst be cancerous? Pilar cysts are almost always benign. Around 3% become proliferating trichilemmal tumours, and malignant transformation to trichilemmal carcinoma is rarer still, usually associated with large, long-standing cysts or prior trauma. A rapidly growing, painful or fixed scalp lump should be evaluated rather than assumed benign.
Do pilar cysts run in families? Yes. They follow an autosomal dominant pattern linked to the PLCD1 gene on chromosome 3. Where a parent carries the variant, each child has roughly a 50% chance of inheriting it, and around a third of apparently sporadic cases turn out to be familial with incomplete penetrance.
Can epidermoid cysts spread to other people? No. They are not contagious and cannot be transmitted by any form of contact. They arise from blocked follicles, skin trauma, or in rare cases genetic syndromes, none of which involve an infectious mechanism.
Why do sebaceous cysts smell so bad? The odour comes from a mixture of keratin debris and lipids that breaks down into volatile fatty acids when exposed to air and bacteria. Pilar cysts contain denser keratin without the lipid component and generally do not smell.
How long does cyst removal surgery take? Most straightforward excisions take fifteen to thirty minutes under local anaesthetic in an outpatient setting. Larger cysts, infected cysts or cysts surrounded by scar tissue take longer.
Will a cyst come back after removal? If the entire wall is excised intact, recurrence is uncommon, at roughly 3% across published series. If the wall is left behind or ruptures during surgery, regrowth is more likely. People with a genetic predisposition may also develop new cysts elsewhere on the scalp after successful removal of existing ones.
Is it safe to leave a sebaceous cyst untreated? A small, stable, asymptomatic epidermoid cyst can be safely monitored. The risk is that it slowly enlarges, becomes infected, or ruptures over time. Removal while it is small and uncomplicated is technically simpler and heals with less scarring than removal after repeated infections.
What is the fastest way to get rid of a pilar cyst? Surgical excision is the only method that reliably eliminates one. No topical treatment, supplement or home remedy removes the cyst wall, and attempting to drain it at home does not work while raising infection risk.
Do pilar cysts hurt? Most are painless. They can become tender if bumped, irritated by hats or helmets, or infected. A suddenly painful pilar cyst that was previously asymptomatic signals inflammation or infection and warrants evaluation.
Can children get pilar cysts? They are uncommon in children and adolescents, appearing most often between twenty and sixty. A scalp lump in a child is more likely to be a different type of growth and should be assessed by a clinician.
What is the difference between a pilar cyst and a lipoma? A pilar cyst is a keratin-filled sac originating from a hair follicle, almost always on the scalp, and it feels firm. A lipoma is a benign fatty tumour that can occur anywhere on the body and feels soft and doughy. Both are benign, but they are entirely different tissue types.
Does OHIP cover cyst removal in Ontario? Not for cosmetic removal. Coverage may apply where the cyst is infected, painful, rapidly growing or otherwise symptomatic, usually via a family physician referral and with a waiting period. Private removal is available immediately.
Do I need my head shaved for scalp cyst removal? Almost never. A small area of hair around the cyst may be trimmed, and surrounding hair typically covers it immediately.
Can several cysts be removed in one appointment? Usually yes, particularly multiple scalp pilar cysts. Your surgeon will advise based on the number, size and spacing of the lesions.
The Minor Surgery Center removes pilar, epidermoid and other benign cysts under local anaesthetic, in-clinic, with every specimen sent for pathology. Consultations are free, and most cysts can be assessed and removed in a single visit.
We see patients across Toronto, Mississauga, North York, Vaughan and Oakville, Markham, Scarborough, Whitby, Newmarket, Milton, Concord, Woodbridge and Barrie. If you are north or east of the city, our guide to cyst removal in York Region explains the options, and you can see the full list of our clinics with addresses and hours.
To have a lump looked at, book a free consultation or call (647) 614-1611.
Further guides worth reading include our overview of 17 types of cysts, our explainer on 25 types of skin lesions, our guide to the types of scalp cysts, our page on finding a skin specialist in Toronto, and our comparison of skin cancer screening clinics across Toronto.
Al Aboud DM, Yarrarapu SNS, Patel BC. Pilar Cyst. StatPearls, NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK534209/
Trichilemmal Cyst (Pilar Cyst): Background, Pathophysiology, Etiology. Medscape. https://emedicine.medscape.com/article/1058907-overview
Cleveland Clinic. Pilar Cyst. https://my.clevelandclinic.org/health/diseases/23092-pilar-trichilemmal-cyst
Hereditary Trichilemmal Cysts are Caused by Two Hits to the Same Copy of the Phospholipase C Delta 1 Gene (PLCD1). Scientific Reports, 2020. https://www.nature.com/articles/s41598-020-62959-z
Clinicopathological factors associated with trichilemmal cysts. 2025. https://pmc.ncbi.nlm.nih.gov/articles/PMC12719779/
Zito PM, Scharf R. Epidermal Inclusion Cyst. StatPearls, NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK532310/
Surgical Excision Versus Incision and Drainage for Epidermoid (Sebaceous) Cysts: A Systematic Review. Cureus, 2026. https://www.cureus.com/articles/453994-surgical-excision-versus-incision-and-drainage-for-epidermoid-sebaceous-cysts-a-systematic-review
Comparison of the Surgical Outcomes of Minimal Excision and Elliptical Excision Techniques in Treating Epidermal Inclusion Cysts: A Prospective Randomized Study. Shiraz E-Medical Journal. https://brieflands.com/journals/semj/articles/55936
Hoang VT, et al. Overview of epidermoid cyst. European Journal of Radiology Open, 2019. https://www.ejropen.com/article/S2352-0477(19)30040-1/fulltext
Leppard BJ, Sanderson KV. The natural history of trichilemmal cysts. British Journal of Dermatology, 1976;94(4):379-390. https://pubmed.ncbi.nlm.nih.gov/1268052/
Brownstein MH, Arluk DJ. Proliferating trichilemmal cyst: a simulant of squamous cell carcinoma. Cancer, 1981;48(5):1207-1214.
Bolognia JL, Jorizzo JL, Schaffer JV. Dermatology. Elsevier. Referenced for histopathological distinctions between pilar and epidermoid cysts.
James WD, Elston DM, Treat JR. Andrews' Diseases of the Skin: Clinical Dermatology. Elsevier. Referenced for clinical presentation and treatment guidelines.
This article is for general information and does not replace individual medical advice. If you have a lump you are concerned about, book an assessment with a qualified clinician.
