Pilar Cysts: What are my options?
Pilar Cysts vs Alopecia Areata
I’ve selected this question below for this week’s question of the week. It allows us to review some concepts in the diagnosis and treatment of pilar cysts also known as trichilemmal cysts and formerly sebaceous cysts.
Question
Do I have Alopecia Areata or do I have Alopecia Areata from pilar cysts? I have attached some photos and provided a full background story.
I have always had Pilar cysts growing up. I had one on my left front scalp back in 2021. I started noticing it getting very inflamed. I went to the doctor in January 2021 and they injected me with triamcinolone to reduce the inflammation (10 mg/cc x 1.0 cc injected total across 1 lesions) the cyst went flat.
Once they did that and I noticed complete hair loss in the area. After two weeks, the cyst got inflamed again so I went back to the doctor in February 2021 and he decided to make an incision and drain the cyst out for me (it was not surgically removed). Once he drained it out, after about two weeks or three weeks I started noticing hair regrowth in the area and the cyst never came back and my hair grew fine.
Fast forward, it is now 2023 RECENTLY I noticed in the same. area where that cyst occurred and the shot of triamcinolone was given to me, a small piece of hair loss in that same area has re-occured. My dermatologist went ahead and injected me with 5 mg/cc, Total volume used was 0.1cc.
Questions on this procedure done above:
1. did the hair grow back the first time because the cyst was drained (I am aware that cysts that cause hair follicles to be blocked so maybe the fact it was drained made a difference for hair to grow back?) or was it due to the steroid shot that was given about a month or so prior to reduce inflammation?
2. is the cyst (no longer palpable and my dermatologist can no longer "feel it") causing this hair loss and the re-occurence of alopecia areata in the area?
Current Situation: Fast forward, it is December of 2022 and I noticed another one of my Pilar cysts, a new one develops in a different area (middle of the top of my scalp this time) starts to get inflamed, I start to notice hair loss again as it gets inflamed and then all of a sudden about a week or two later the cyst goes back down on its own and becomes completely flat with complete hair loss in the region where the cyst is. I went to a dermatologist in the US and she said since the cyst went back down on its own, I shouldn't remove it surgically because even when she touches the area she doesn't feel anything except a bald spot, she claims she feels no cyst anymore, so instead she suggested I should just take a shot of kenalog for hair regrowth. she injected me with (Kenalog 5mg/cc 0.2ccs was injected into the lesion.) this was done in December 2022. it is now January 18th, 2023 and I have seen very little hair regrowth ( and I had her use a dermascope to look at it and her words were "I see some hairs regrowing, nothing overwhelming but there is some growth and I am hopeful for the future".
Questions + Concerns: 1. It has been over a month at this point when I got the steroid shot, should I go back and get more? if so, at what dose? or should I wait even longer to see if hair continues to grow? WHAT DO I DO NEXT? 2. Is the hair loss caused by the cyst? 3. should I get a biopsy of the area to see if the cyst causes the hair loss? (because I went to a dermatologist in US and she said the hair loss and cyst is not related but that doesnt make sense to me because everytime my cysts get inflamed that is when I get hair loss in the region of where the cyst is.) 4. will the shot of kenalog she gave me work for hair growth even though I didn't remove the cyst (since cysts cause hair follicles to be blocked?) She says that she can no longer feel a cyst on the head when she touches the bald spot, therefore she is skeptical to even open up the area and cause any scarring incase she doesn't find anything when she does this?)
original appearance of pilar cyst.
original appearance of pilar cyst.
appearance of pilar cyst after steroid injection
Answer
Thanks for the question. These are pilar cysts and there is no evidence in what you have written or shown for alopecia areata so I won’t discuss that further. Alopecia areata does not appear to even be in this discussion. If there are features of alopecia areata you see in other areas, be sure to review with your doctors. I don’t see evidence for alopecai areata in what has been presented here. Yes, they can look similar. But there are 10 different things that cause circular areas of hair loss like this.
So, we’re dealing with pilar cysts, also called trichilemmal cysts. About 5 % of the population has them and they an often be multiple. Often there is a family history in mom or dad too - but there does not have to be. Some just crop up sporadically with no such family history. They are more common in females than males but both get them. Young females are particularly a common group.
The key on what to ‘do next’ for anyone depends on a few things:
a) does the cyst come back (reform) after injections?
b) do they come back with one drainage?
c) are they causing hair loss when they occur? and is it permanent or temporary
d) are they causing pain?
e) how inflamed do they get?
f) how much trouble to they cause?
The reality is that once someone has a cyst, there is a good chance it is not going away unless the entire cyst is removed from the scalp. I’m not talking about being drained - but actually removed. Removal (when inflammation is low) is often the best plan for a lot of people. Not everyone needs them removed- but many prefer to. Now, if the cyst is small and not causing hair loss and not causing pain or irritation it’s fine to leave it. But it’s unlikely to go away. Many people live with tiny bumps and domes in the scalp and they are hidden away. They don’t cause problems in most cases.
So for many people, pilar cysts are just left alone if they don’t are not causing problems. If they get inflamed and puffs up, one can try a steroid injection like you did, to see if they settle down again and return to a quiet state. But if they don’t settle or just keep getting inflamed (or infected), surgery may be the best plan. You’ll know over time how much trouble a given pilar cyst causes - and the best plan. Your doctors can help with that.
Your story really should be reviewed with a dermatologic surgeon. You have new cysts forming and you have recurrent cysts in prior areas that were drained. It’s not surprising that prior areas are getting the cyst again - because unless the entire “wall” of the cyst is removed, it can just fill up again and possibly even rupture. We really want to prevent that because sometimes repeated rupture can lead to scarring in the scalp. If cysts are repeatedly getting inflamed, it’s often sign that serious discussion about removal should take place
Surgery can be helpful once the inflammation has settled. Generally speaking, the best time to remove a pilar cyst is when it’s not inflamed. With surgery, the chance is around 2 % that the cyst will come back again in that same spot. That’s assuming the entire capsule of the cyst was removed. If the entire wall was not removed, there is a 25-50% chance this will keep coming back. So with drainage of the cyst, the wall does not get removed at all, and so there’s a very high chance it will just reform again in the future. For an occasional patient, drainage along (rather than surgery) does solve the problem and gives long term relief. But for many, the cyst just comes back with things like drainage or steroid injections. The purpose of a trial of drainage is to give relief of the pain, stop inflammation and settle things down. The purpose of the steroids is to chase away inflammation that contributes to redness and pain and swelling. But drainage does not cure these cysts - nor do injections. They just help settle things down.
You have asked which of the two helped the hair come back. It’s likely both.
It makes sense at this point to have a plan in place for what to do for the current cysts and any future cysts that form. It’s likely there could be another cyst in your lifetime. This is something you are your doctors can decide. Often, if they don’t bother a person, they are left or removed immediately when not inflamed (before the cycles of inflammation and rupture start). You’ll know over time what feels right for you but the key is to remove them when they are quiet (if one decides to remove them).
As for the present ones, it is a combination of pressure and inflammation that is causing the hair loss. Hairs don’t grow well when all this inflammation is around and don’t grow well when under pressure. If there has been any infection of the cyst over time, that’s going to affect things too.
I usually advise my patients to watch carefully over time what their cysts tend to do. If they remain small and stay quiet, then watchful waiting is a good idea. If a person’s cyst tends to grow and rupture or grow and become inflamed or grow and cause hair loss, then removal of new cysts rather soon in their evolution may be a good idea.
As for the cysts that are present, it would appear that the newest one has settled nicely. It has a high chance to return again at some point but also currently has a high chance to regrow hair. For many of my own patients, I inject again in 2 months (often with 2.5 to 5 mg per mL) and have the patient use topical minoxidil over the area for 4 months (if there are no ‘contraindications’ or reasons not to). This second cyst area has a high chance of hair regrowth but it has a high chance of coming back in the future. You’ll need to decide with your doctor if you want to just wait and see what happens in the future and excise it if it does come back.
As fas as the first area goes, this is behaving exactly as we expect. The area settles and then slowly fills up again and comes back. Periodic steroid injections are an option but if you find it happens too often or you find the hair is not growing back completely, then removal may need to be considered.
A word about steroid injections before we leave this topic. For some patients, 10 mg per mL is a good dose and for others 5 mg per mL is a better dose and less likely to trigger hair loss. This is something you and your doctors can review. All in all it would appear you have been getting very little in the way of steroid so I don’t think the dose is likely much of an issue for you.
In summary, it’s a combination of inflammation and pressure that is causing the hair loss - with the bigger contribution generally being the inflammation at this point for you. Steroid injections settle both. Incision and drainage relieves the pressure.
You are your doctors can decide if periodic steroid injections and drainage is the right plan for you or whether surgical removal is the best plan. If the areas are filling up too quickly or are causing hair loss or too much days of pain or tenderness or there is a worry about any kind of permanent hair loss (from repeated inflammation), then excision often becomes the right plan.
if this always grows back fine and it’s once every 10 years that you are dealing with inflamed cyst issues, then a conservative approach may be best. If it’s every 3-6 months that you’re dealing with cyst issues and it’s affecting how you feel and look, then a more aggressive approach may be right to you.
All this takes some good discussion with a knowledgable physician.
There is no right or wrong answer for pilar cysts. Some patients live with them if they don’t cause issue. Others get them removed if they are tending to become inflamed or infected or carry a risk of temporary or permanent hair loss. Some get them removed quickly when the pop up and others get them removed after many years. You’ll know what feels right for you.
The goal now is for you to develop a plan that suits you the best. Some patients will say “I’m going to inject this now and if it comes back ever again I’m going to have it removed” Other patients will say, “unless it causes hair loss or becomes inflamed I’m just going to leave it alone. If it does’t bother me then I’m not going to bother it.”
it would appear that your cysts are teaching you and your doctors that they tend to return and carry a risk of temporary hair loss when they do occur. This makes discussions about removal in the future all the more important. But these are really important discussions that you and your doctors will want to have. It’s great that regrowth is ocurring. It can take 3-5 months for regrowth to occur. - assuming inflammation has settled.