Scalp Biopsies Helpful to Confirm or Refute Suspicions
Scalp biopsies are very brief procedures that result in a tiny core of tissue being taken from the scalp and tend off to a pathologist for analysis. Scalp biopsies are not necessary for every patient with hair loss since most of the time the diagnosis of a patient's hair loss can be made by listening to their story, examining their scalp up close and reviewing relevant blood tests.
When one can't be certain of the diagnosis, a biopsy might be considered. There are many hair loss conditions that resemble each other and a biopsy is helpful to differentiate between these mimickers. For example, some forms of lichen planopilaris (a scarring hair loss condition) can look nearly identical to some forms of androgenetic alopecia (a non scarring hair loss condition). In addition, some forms of diffuse alopecia areata (an autoimmune condition) can resemble telogen effluvium (a hair shedding condition). A biopsy can help sort things out.
Reasons for a Scalp Biopsy
In general, I perform a biopsy in about 1 out of 7 patients that come into my office. One can see that the number is not 7 out of 7 and not even 5 or 6 out of 7. A scalp biopsy is performed for many reasons
1. To differentiate between two "look-alike" conditions
2. To refute the current diagnosis that the patient is thought to have
Using a Biopsy to Refute the Current Diagnosis
I sometimes perform a scalp biopsy to refute a diagnosis that the patient or his or her doctor thinks they have (i.e. the current so called "working diagnosis"). There are times, where a diagnosis just doesn't make sense. It simply doesn't fit. A biopsy can be helpful in these situations to re-direct the patient and their physicians to the proper diagnosis. Interestingly, in some of these situations a biopsy has already been done - and I still won't agree with the results. Let's take a look at a few examples of how a biopsy can be used to "refute" a diagnosis.
1. I frequently perform a scalp biopsy in young men under 25 who have been given a diagnosis of telogen effluvium or chronic telogen effluvium.
Telogen effluvium and chronic telogen effluvium are hair shedding conditions. Telogen effluvium can occur in men and certainly does occur in men. However, it is far less common than in women. When I see a young male patient who thinks they have telogen effluvium (or whose physician thinks they have telogen effluvium), I'm always on high alert. I need to answer three questions before the patient leaves:
Does the patient really have a "TE"?
Does the patient have "TE" PLUS another diagnosis (like androgenetic alopecia, "AGA")
Does the patient not have "TE" but rather really a diagnosis of "AGA" (male balding) ?
It is not well known that there are many mimickers or 'lookalike' conditions that frequently lead to incorrect diagnoses of telogen effluvium in men. A good example of this is the early stages of male balding (AGA) in men. Men with early balding experience increased hair shedding which looks very similar to a telogen effluvium. Many such men are given a diagnosis of TE when in fact the correct diagnosis is AGA. To complicate matters slightly, some men have an initial TE that ultimately speeds up their arrival of genetic hair loss. The most important question that should be asked in any male with a diagnosis of suspected telogen effluvium is: does this patient actually have androgenetic alopecia instead of telogen effluvium OR does this patient ALSO have androgenetic alopecia together with telogen effluvium?
I would like to point out that telogen effluvium can occur as a sole diagnosis in men. However, more times than not in the patients I see, TE is not the only diagnosis that is present in a young male patient.
2. I frequently perform a scalp biopsy in individuals under 40 who have been given a diagnosis of "scarring alopecia" if clinically there does not appear to be a scarring alopecia.
It comes as a surprise to many people that a biopsy is not the the final answer in the field of hair medicine. It's not the ultimate 'last step' in diagnosing hair loss. That would be nice. But it's not. In some parts of medicine (like cancer diagnoses for example), a biopsy is frequently the last step en route to solidifying a diagnosis (whatever the pathologist says in his or her report is the final answer).
A biopsy is a tool that given power information. But the patient's story itself also represents a powerful tool - and details of their story can sometimes trump a biopsy result. One should never perform a biopsy "just to perform a biopsy." This often leads to confusion with the final diagnosis. In the same line of thinking, one should never hand over their biopsy to a pathologist unless that pathologist has significant experience in diagnosis hair loss by histology. That too leads to confusion. I have filing cabinets full of examples of these examples, but I'll share a good example here.
Consider the 37 year old woman who comes to see me devastated about a diagnosis of scarring alopecia that was made by biopsy. I first listen to her story. There is a history of slow and steady hair loss. There is a bit of itching in the scalp. There's no real scalp burning or scalp pain. She experiences more hair shedding that normal - and there's a bit more hair on her bathroom floor than normal. Her blood tests are pretty normal. When I look at her scalp I see that she's lost most of the hair in the centre of the scalp. It's a bit red in areas, but nothing too unusual. When I use by dermatoscope to look at her scalp, I see hairs of all different diameters. But nothing else is all too concerning. I pause and read the biopsy report. It shows reduced density with inflammation in the scalp. There is scarring (perifollicular fibrosis) around the hair follicles. A diagnosis of scarring alopecia is noticed in the report.
This situation is not so uncommon. At first glance it seems pretty straight forward. A biopsy shows scarring and so a patient is given a diagnosis of scarring alopecia. What I'd like readers to appreciate today is that many of these patients don't actually have a diagnosis of scarring alopecia. Some of course do.
What is often not appreciated is that biopsies of patients with androgenetic alopecia (male balding and female hair loss) frequently shows scarring (i.e. perifollicular fibrosis) and frequently shows the presence of inflammation. There's more to diagnosing scarring alopecia than just these two points. These two pieces of information alone do not give a diagnosis of scarring alopecia. What I need to read in the report, and what the pathologist needs to comment on - is features that would sway the diagnosis more towards a definite diagnosis of scarring alopecia. These include a) reduced density of sebaceous glands b) specific changes in the hair follicle (necrotic keratinocytes, lichenoid change in the case of LPP and FFA), as well as other features too (presence or absence of mucin, presence or absence of inflammation in the blood vessels).
In summary, one can immediate tell if a biopsy report they are reading is a 'good' biopsy report or a 'poor' biopsy report. A poor biopsy report can still be right, but is less likely to be right if it just doesn't fit with the patient's clinical features. If I see a patient whose history, examination and blood test suggests that what we are dealing with is unlikely to be a scarring alopecia, I perform a second biopsy even if a first biopsy is suggesting a diagnosis of scarring alopecia.
3. I frequently perform a scalp biopsy in patients who have been given a diagnosis of telogen effluvium, chronic telogen effluvium or androgenetic alopecia if they have marked scalp symptoms such as itching, burning or pain regardless of whether I see scarring on on the scalp.
The early stages of scarring alopecia happen beneath the scalp and then 'show up' on the surface a bit later. It's not the other way around. The earliest stages of scarring alopecia are often associated with the immune system becoming active deep under the scalp followed by the development of scar tissue deep under the scalp. Soon into the course of a scarring alopecia, it comes difficult for hairs to grow and so many hairs shed. Later on the presence of deposits of scar tissue act like cement and make it impossible for a hair to push back up. The result for the patient is permanent hair loss and patches of scarring on the surface of the scalp.
The key point here is that the very earliest stages of scarring alopecia don't look strikingly like a scarring alopecia. They can look either normal, or be associated with a bit of increased shedding, (i.e. an trigger a physician to think it's a diagnosis of telogen effluvium). In some cases the whole set of events brings the patient's hair loss to focus where they may never have noticed any hair loss before. The patient may have had some minor degree of balding (androgenetic alopecia) present for years without them even knowing. Not surprisingly when they now go to visit the doctor, the immediate response is "Oh, you have some genetic balding." It will take a bit longer for the patient to actually receive the correct diagnosis "You have some genetic balding as well as some scarring alopecia."
The presence of scalp symptoms like burning and tenderness should cause all patients and their physicians to take note. There are many many reasons for these types of symptoms and certainly not all represent scarring alopecias. But unless one recognizes the possibility that a patient with symptoms of scalp burning and scalp tenderness 'could' have a scarring alopecia - these conditions will continue to be under-diagnosed and under-recongized around the world.
There are many situations where a biopsy is appropriate. But a biopsy should never be performed 'just because.' It's a bad idea to perform a biopsy 'just because' a friend also had one. It's a bad idea to have a biopsy 'just because' one feels it completes the work up. A biopsy should be done with a purpose. A biopsy result is not a stand alone result. It needs to be interpreted with the entire clinical picture. For this reason, I never accept a consult for a patient who 'want me to look a their biopsy result and tell me what I think." A biopsy result can only be interpret fully when I know everything about a patient!
A biopsy is a great tool to refute a diagnosis. When a 22 year old male walks in and tells me they have been told by 4 dermatologists they have telogen effluvium, by first thought is "wow that would be uncommon but let's see if he's right." My second thought is frequently ... "perhaps we need a biopsy to get back on track." This is the same line of thinking with many patients who come through the door with biopsies showing 'scarring alopecia' when it's clear that it just does not make sense.
Biopsies are a wonderful tool, but need to be used properly.
Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Whistler office at 604.283.1887