acoustic neuroma vs. wart, skin tag, etc.

[km5]

Hello everyone,
I have written previously about my 23-yr-old son's AN measured at 4 mm.  We have been watching and waiting as we now believe that he has had the exact same hearing loss since he was 5.  The AN has not grown during 2 MRIs, another one is scheduled.  Son says his right ear high frequency hearing has been the same (not good) for years.
A question in my mind has come up:  Our family has a lot of moles, skin tags, dermatofibromas (one parent and two children have them).  We just generally have little small things growing on our skin.
What makes a radiologist so sure that a growth in the shape of a pea in the ear canal is in fact an acoustic neuroma?  My understanding is that until it is taken out in a surgical procedure it can't be analyzed for sure.  Could it just as easily be something else, particularly since it may have been with our son since birth?
Thank you all again for your thoughts.
Katherine

[leapyrtwins]

Katherine -

these are great questions to ask your doctor.

Also, is it possible that your son is NF2?

Jan

[Migoi]

It is my understanding that the term 'acoustic neuroma' can best be thought of as a fairly broad term meaning a non-cancerous growth affecting the acoustic (and/or the vestibular and facial) nerve.

These neuromas can have as their source different cell structures. Some arise in the schwann cells, those cells forming the lining or insulation layer, of the nerves. Or, as in my case, the neuroma can have as it's source the cells from the meninges (the lining of the brain). If it comes from the schwann cells it can be called a schwannoma. If from the meninges cells it can be called a meningioma.

Mine was a meningioma but can still accurately be called an acoustic neuroma due to its location...completely within the IAC (internal auditory canal, if I got my initials correct) and it was affecting the acoustic, vestibular and facial nerves. We did not know it was a meningioma rather than a schwannoma until the lab report came back after the surgery.

The only real difference in my case was that because it was a meningioma it wasn't as "stuck" to the nerves as schwannomas can be and I had better outcomes post surgery because they didn't have to hack at the actual nerves as much to get it out. The other difference is that in my yearly followup MRI's we look closely at my whole head instead of just the IAC area since there is a slight possibility of developing another meningioma.

You certainly should ask your doctor, because I'm not one nor do I play one in health care town hall meetings, but I would think that treatment options would be based on growth rates, location, and affects on functioning of various nerves in the area.

At the symposium there were two doctors from the University of Michigan, Steve Telian and B. Gregory Thompson who are using MRI's from machines with a higher quality magnet on very small tumors to be able to see exactly which nerve the AN is on. They are also carefully screening certain patient and operating on smaller tumors with the goal of greater hearing preservation.

I mention this because if there is a possibility of your son's AN having a source other than meninges cells or schwann cells (I don't know if there are other cells in that area that could develop growths) then one of the super duper MRI's might be able to distinguish well enough the location to make that determination.

No answers... but I would think the following questions might be a place to start when you next visit with the docs...

1. Are there other cell types in the area besides meninges and schwann cells that could the the source of the growth?
2. Are there different treatment options depending on the source cells of the growth?
3. Is there a non-surgical way of determining the source cells of the growth?

Again, no answers, and certainly not a comprehensive list of possible questions...just a possible place to start.

Info overload avoidance hint... write down the questions you want to ask prior to arriving at the doctor's office and take notes as he's answering. If he's going too fast, ask him to slow down... it's your head (or your son's in this case), you (or your son) needs to be in charge of the pace of what happens.

good luck and take care... tim b

[Lilan]

Tim gave a very detailed answer with some smart questions. I would add that the things you mention in your post are skin growths -- and an AN does not arise in an area with skin. So literally, no, I don't think it could be a wart or skin tag.

Could it be something other than an AN? Yes, but as I learned from experience, it doesn't matter all that much, in that any type of "growth" in that area ultimately acts like an AN (putting pressure on the same nerves), leading to the same symptoms and same outcomes and same treatment options (though radiation was not an option for my type of tumor, a hemangioma, it still would be for some of the other possible variations, like a meningioma, I believe.)

ANs are the usual assumption because they are by far the most common tumor in that area, and they have a characteristic shape. A CT scan can provide additional information if there's a reason to look for something else. As young as he is, and if he's had hearing loss for awhile, I wonder if they will investigate NF2, as Jan suggested, or other rare types of tumors like even a hemangioma (which are present from birth?) But if you are WW and symptoms are not progressing, maybe you can just go on like that!

I know you must be terribly worried about your son -- I kept thinking the only thing that must be worse than contemplating this surgery for yourself is contemplating it for a child! But if you view surgery as a "worst-case," based on my own experience, I am quite sure your young, healthy son would do just fine even if he wound up having to go that route!



 

[km5]

Thank you all for your thoughtful responses.  What you are all saying is so logical:  the ear canal is not "skin" so it's not likely that it's a "skin growth."  I don't think it's a NF2 because only one ear has ever been affected, and the exact same loss has been constant throughout his life.  It's now one year, and he has another appt with ENT to get approval for MRI.  We might as well have MRI again as we are paying exorbitant Cobra insurance costs to keep our dear boy insured now that he has finished college.  The ENT, however, was quite proud that he recognized the AN symptoms (I do applaud him for that) and that he also has a personal relationship with Dr. Brackman at House, who wanted to cut it out right away.  Luckily we did some additional probing and consulting with Dr. Chang at Stanford, and then the light bulb came on re our son having the same hearing loss since he was a little boy.  When we found his audiograms at 5 yrs old we knew we had plenty of time to prolong a decision.
So, I am a big fan of lateral thinking...and keep trying to come up with other angles...thus, the question, how do we even know it's an AN?  Thank you all again.
Katherine

[jerseygirl]

Katherine,

Dermafibromas on the skin and an AN may signal NF1. Nf2 is bilateral acoustic shwannomatosis  which thankfully your son does not qualify for. Nf1, however, has a lot of skin involvement and AN is very rare in this syndrome. It is always unilateral. I suggest that your son be evaluated at a local Neurofibromatosis center. They will be able to give you more information. I am not sure where you live but usually they are in a big hospitals. Good luck!


               Eve

[Lilan]

Thus, the question, how do we even know it's an AN?


I forgot to mention this earlier, but there are also signs on the gad-MRI that tell the radiologists things about what it might be. If you read things about diagnosis, there's a lot of stuff like "hypointense on T-1-weighted images" and whatnot that all gives them a clue as to which type of tumor it is.