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Vestibular schwannoma, 25x18x18 mm, 30 years old
triplewave
Posted: Sunday, October 22, 2017 11:43 PM
Joined: 10/22/2017
Posts: 1


I’m 30 years old and was recently diagnosed with a 25x18x18 mm vestibular schwannoma. The first sign of the problem was 2 separate episodes of sudden hearing loss 2 weeks apart, one lasting 3 days and the second lasting 6 days (treated with prednisone the 2nd time). My hearing is back to normal now (100% based on my latest audiogram). The only other symptom I've had is a feeling of pressure on my skull near where the tumor is, which may be imagined. I talked to several surgeons last week. The general consensus is that radiosurgery is an option, but I should go with microsurgery. I'm on the fence since radiosurgery has a much greater chance of preserving my hearing (especially CyberKnife, which seems to have an advantage over GammaKnife for hearing preservation), but microsurgery is more likely to control the tumor without additional treatment and doesn't carry the risk of radiation causing problems 15-50 years from now. I'm trying to answer several more questions now: 1. Is there any merit to the argument that we simply don’t know what effects radiation will have on my brain 15-50 years from now (dementia, cancer, other neurological/cognitive problems)? Will I live my entire life thinking that every cognitive change/issue I experience is somehow a long term effect of the radiosurgery? 2. How much radiation exposure is the surrounding tissue actually receiving compared to common radiation sources (airplane flights, CT scans, etc.)? Most doctors talk about a ~12Gy dose to the tumor, but I don't really know how to put the GK/CK dose to the surrounding tissue into the perspective of something like the XKCD radiation dose chart (xkcd.com/radiation). 3. IIUC, the facial and hearing nerves (and all nerves touching the tumor) would be irradiated at the same dose as the tumor since they lie on its surface, and they may become devascularized from the treatment. Does this have any effect on the function of the nerves, or is this just a problem in the case where I need surgery later? 4. One surgeon is concerned that given my young age, the tumor is likely to be growing more aggressively than average and thus the chance of radiosurgery killing the tumor less likely than the 92-93% average (across all ages, for my tumor size) that I've heard. Looking for research that would address this claim.
9/3/17 - Sudden hearing loss on left side. Hearing returned 3 days later. 9/17/17 - Sudden hearing loss on left side. Started taking prednisone. Hearing returned 5 days later. 10/5/17 - Diagnosed with 25x18x18 mm left side AN (age 30)
radsrus
Posted: Monday, October 23, 2017 3:55 AM
Joined: 10/10/2008
Posts: 4435


Of course surgeons told you you should have surgery.; There is not any good data showing better outcomes with surgery. With CK you get about 92-98% control, and it would be hard to improve on that with surgery. You would have to have a study involving thousands of randomized patients to show a difference. Surgery has a significant risk of facial nerve injury. 1. There is no evidence that the very low dose received by the normal brain is harmful. Whether you will think that there is a problem is more dependent on your psychological make-up. 2. Dose to surrounding brain (usually cerebellum) is extremely low. The team does have to be sure that they restrict the dose to the brainstem, but is easily done with proper technique in almost all cases. If that cannot be accomplished, then they may be better off doing surgery, but that cannot be known until they start planning the CK treatment. 3. We have very limited experience with surgery after CK since we have only had one CK failure, but the surgeon did not record it as being a problem. We have never seen facial nerve injury other than a couple of cases of temporary hemifacial spasm. We have never seen any other cranial nerve injuries. The deeper argument is this - why would you accept a risk of about 15-20% of facial nerve injury right now to avoid a 2% risk of needing surgery later. 4.We have treated people of all ages, and have not found any difference in outcomes. Surgeons are always likely to recommend surgery, and they often introduce scare tactics into the discussion, either deliberately or as a result of a sincere belief they took from their training.

Clinton A. Medbery, III, M.D. Southwest Radiation Oncology buddy@swrads.org
radsrus
Posted: Monday, October 23, 2017 3:55 AM
Joined: 10/10/2008
Posts: 4435


Get on the Acoustic Neuroma Association website.

Clinton A. Medbery, III, M.D. Southwest Radiation Oncology buddy@swrads.org
 

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