Do I need a scalp biopsy?

Most patients don’t need a scalp biopsy

The diagnosis of hair loss is often reached by listening to the patent’s story and then examining the scalp up close. For most people that’s it. 99 % of people in the world with hair loss can be diagnosed without ever needing a biopsy. Even in a specialized hair loss clinic like we have where I meet patients with lots of atypical and unusual stories and rare diagnoses - only 15 % of patients that walk through my office door really need a scalp biopsy.

Some patients will still really want me to do a biopsy after I explain their diagnosis to them. They might say to me “Don’t you want to confirm the diagnosis, Dr. Donovan?”

Depending on the patient, I may joke and say to them “That’s such a good idea!” ….. I will go back to examining their scalp again and then reply “Ok, I confirmed it!”

(Not everyone appreciates the meaning of this gesture - so I reserve that for only for a rare patient. But for many patients it puts them at ease that we have the diagnosis and can move on to discussing treatment).

The point of doing that is to emphasize that we don’t always need a biopsy to be 100 % sure of the diagnosis.

There are lots of examples in medicine where we have other tests available to us but we don’t need to order those tests just for the sake of ordering them.

For example, If a patient comes into the emergency room feeling unwell and the health care team finds out that the patient has a blood sugar level that is super high, he or she has a diagnosis of diabetes. End of story. We don’t need a fasting blood sugar, or any fancy tests (like hemoglobin A1C). That patient in the emergency room has diabetes. Sure, we can order other tests to get more test results that show the same thing. But it’s not needed.

So who might benefit from having a scalp biopsy ?

Criteria and Indications for having a scalp biopsy

A scalp biopsy may be helpful if ANY of the following are found to be true:

1. The diagnosis can not be confidently determined after careful review the patient’s medical history, examination of the scalp and review of blood tests.

   In many cases, the diagnoses still being considered by the hair specialist can look identical and a biopsy is needed to differentiate between them. For example, in a patient with chronic hair shedding that is not getting better, a biopsy might be helpful to determine if the cause of the shedding is due to telogen effluvium, androgenetic alopecia, alopecia areata diffusa, or lichen planopilaris. These 4 conditions can usually be distinguished with careful attention to the patient’s history and scalp examination finings - but not always ! To give another example, sometimes patients with red, itchy or tender scalps benefit from a scalp biopsy because conditions such as scarring alopecia, lupus, psoriasis, contact dermatitis, seborrheic dermatitis can look similar.

2. The patient has received a DIFFERENT DIAGNOSIS from two or more specialists and a biopsy can potentially help differentiate between the two different conditions.

   For example, if one specialist feels the patient has genetic hair loss and a second specialist feels the patient has telogen effluvium, a scalp biopsy might help determine which specialist is correct so that the patient can get started on the correct treatment. A patient needs an accurate diagnosis before the correct treatment plan can be started.

   If the two specialists feel there are two different diagnoses but a biopsy can not tell them apart, a biopsy is useless. For example, if one specialist feels that the correct diagnosis is frontal fibrosing alopecia but the second specialist feels the diagnosis is lichen planopilaris, a biopsy is not going to sort out who is correct because the biopsy findings are identical.

3. The patient has received specific diagnosis through a biopsy in the past but the hair specialist examining the patient today feels that a brand new diagnosis has now surfaced. For example, if a patient has been told they have androgenetic alopecia, but the hair specialist examining the patient today feels that the patient once had a diagnosis of androgenetic alopecia but now has a second new condition present, a biopsy is potentially going to be helpful.

4. The patient has already had one or more scalp biopsies but the diagnoses suggested by the pathologist do not seem consistent with the clinical picture and clinical diagnoses that are being considered. For example, if the biopsy returns showing evidence of a scarring alopecia but it does not seem that this could possibly be true based on the patient’s story and what the scalp looks like, a repeat biopsy might be indicated.

5. The patient received a diagnosis in the past but is not responding to treatment in a manner that would be expected for that diagnosis. For example, if a patient received a diagnosis of telogen effluvium due to a thyroid disorder and hair shedding is continuing for many months after the thyroid issues were completely corrected, one might consider revisiting the diagnosis again. A biopsy may be indicated.

Common Myths and Misconceptions

A biopsy is NOT necessarily needed “just because” the following are found to be true:

1. There are no triggers found for the hair loss. I have often heard it said that if there are no triggers to the patent’s story of hair loss, they need a biopsy. That’s just nonsense. Many hair loss conditions do not have identifiable triggers. If the diagnosis can be made with proper history, scalp examination and blood tests, a biopsy is not needed for all cases of hair loss that lack a triggering event. If the cause of the hair loss can not be precisely determined following careful review of the history and thorough examination , a biopsy is probably required.

2. Severe hair loss. I have often heard it said that if there is severe hair loss the patent needs a biopsy. That too is incorrect. In fact, severe hair losss is often much much easier to diagnosis that early hair loss!!! It’s the early stages hair loss that are so so tough to diagnose NOT the severe end stage hair loss. severe hair loss is easier to diagnose because all the clues are present on the scalp for the doctor to see!e

   If the diagnosis can be made with proper history, scalp examination and blood tests, a biopsy is not needed for all cases of severe hair loss. If the cause of the hair loss can not be precisely determined following careful review of the history and thorough examination , a biopsy is probably required.

3. Acute hair loss. I have often heard it said that those with sudden hair loss need a biopsy. No, that is simply incorrect. If the diagnosis can be made with proper history, scalp examination and blood tests, a biopsy is not needed for all cases of acute hair loss. If the cause of the hair loss can not be precisely determined following careful review of the history and thorough examination , a biopsy is probably required.