I found some interesting statistics

[TOM101]

http://www.patient.co.uk/doctor/Acoustic-Neuromas.htm

This is the kind of statistics I was looking for to determine watch and wait. In the UK they did autopsys and discovered 8,000 cases per million of AN's. We are told 1 in 100000.  If there are 8000 not discovered then what are our chances?
What we dont know is if they had any symptoms. Are there any watch and waits that had their tonsils  out with radiation in the 40's or 50's ? Iwould like to hear from you to compare notes, as this article states that this is a definate risk factor for AN. Todays tonsil cancer articles that I have read talk about Schwann cells in the tonsils.

[Tumbleweed]

Thanks so much for posting a link to this research, Tom! I found it fascinating.

One of the things that struck me was that complete tumor removal is possible in 95% of the cases in the UK. Seeing as recurrence after surgery only occurs in about 2% of patients, this would indicate that many patients who don't have their tumor completely removed nevertheless don't see regrowth -- or at least not during the term of the study cited.

I also found the suggestion that hay fever may be a cause of ANs very interesting. I had terrible hay fever right around the time I estimate (based on 2mm/year growth projections) my AN started. Who else on this forum has or has had pronounced hay fever?

Thanks again,
TW

[jerseygirl]

This is absolutely fascinating! Thanks for posting it. Most of the studies, especially long term, come from UK. They seem to do a better job than US in tracking and evaluating AN incidence (not treatment!).

TW, I had terrible hay fever in the past. It became better over the years but my childhood was a nightmare because of it. Very interesting!

         Eve

[Tod]

It is a very interesting article.

I am struggling with the studies referenced in the footnotes:

An autopsy study by Leonard and Talbot (1970), suggested a prevalence of 0.8 % or 8,000 per 1,000,000. If one accepts the clinical incidence of acoustic neuromas as being between 13 per 1,000,000, it is reasonable to assume that many neuromas escape diagnosis.

I really have trouble reconciling a difference on an order of magnitude between the two studies without resorting to believing that the 1970 study is very flawed. In searching Google Books, I found an analysis that criticizes that study and others as being "biased to temporal bones with pre-existing hearing disorders." In other words, the results were not generalizable to the population. On the other hand, another, apparently less biased, autopsy study suggests a similar rate of occurrence. So maybe it is not so flawed.

As I look around for other articles, I keep finding references to this study and Anderson et al (2000) MRI study and I found an interesting presentation http://www.scribd.com/doc/37367737/Acoustic-Neuroma-web-Presentation. This may be helpful to some, but despite some positive findings  on W&W, it does close with a clear bias towards treatment.

-Tod

[Tumbleweed]

Tod, thanks so much for the link!

One of the things I found interesting in this presentation you provided the link for is the statement, "Deterioration in PTA and speech discrimination occurred regardless of whether radiological growth was demonstrated or not." In other words, people lost more hearing even if their tumor didn't grow.

Also: "Growth rate at 1 year follow up was a strong predictor for eventual need for treatment." What I glean from this is that if your AN has shown growth in the first year after diagnosis, you should probably get treated in a timely fashion because you're eventually going to need to be treated anyway. And based on the first excerpt immediately above, the longer you wait to get treated, the more likely it is you'll lose more hearing. This jibes with what Dr. Chang told me when I was in W&W a few years ago. He told me at that time that the sooner I got treated, the more hearing I could retain.

The presentation also reported that, of patients with an AN  between 2 and 3.9 cm at the time of surgery (surgical resection), 26% had their facial-nerve function deteriorate from Grade 1-2 (House and Brackmann) to Grade 3-4. With radiosurgery, there was between a 1.3 to 4.2% chance of facial palsy.

In the Sterkers study, 91% of patients had their tumors totally excised and 6% had recurrence. I wonder if this is outdated data (no dates were cited for Sterkers, but the presentation stated at the end that some of the data from all the studies cited date back to the late 1960s "and do not completely reflect outcomes using current imaging and procedures"). But at face value, it brings into question the rationale of choosing surgery "to just get it removed and be done with it." 94% chance of not having recurrence is still great odds, but people who choose surgery over radiation just so they can have finality should realize it's not necessarily a done deal. The report also cited between 2 and 8% chance of recurrence with radiosurgery. No matter which form of treatment you choose, there is a small chance of regrowth.

Best wishes,
TW

[annamaria]

It must be kept in mind that the often quoted statistics of 1 in 100000 diagnosed cases (or, some even quote 5 per 100000 diagnosed cases) is a YEARLY INCIDENCE FIGURE, not an absolute figure. It should be properly stated as "1 in 100000 per YEAR".

Now, assume that life expectancy is 80 YEARS.  Then, ACCUMULATED over the 80 years, the chance that one person got an AN would be 80-in-100000 (or even 400-in-100000 if we use the higher figure). [That cumulative risk is roughly 1-in-1000]

With this in mind, in 1 million people, one would expect to find 800 (or even 4000 if one used the higher figure.) That is reasonably close to the 8000 cited in the thread, if one assumed that only a portion of ANs are actually diagnosed when one is alive (some being found only in autopsies.)

Annamaria

[CHD63]

Tom .....

I am not wait and watch.  My 2.6 cm AN was removed via retrosigmoid approach in February, 2008.  However, I did have "radium treatments" following a tonsillectomy/adenoidectomy in the 1950s.  I also had severe hay fever as a teenager/young adult ...... it disappeared after the birth of my first child.  I suddenly lost the hearing in my left ear in November, 2007.  I had had balance issues for several months prior to that.  An MRI in November of 2006 showed no tumor; MRI in January of 2008 showed a 2.1 cm AN; post-op pathology a month later said the tumor was 2.6.

Thanks for posting the article ..... very fascinating ..... guess I was pretty typical given my history.

Clarice