Hi guys!
My wife and I attended the Acoustic Tumors "Current Management Strategies and 3-D Live Surgical Simulation" seminar. First - WOW! Some of the research is surprising! A study from Stangerup et al. Otol Neurotol 2006 found that tumor growth was greatest in the first year of detection, then dropped off significantly after that. Most tumors stopped growing by the 5th year. 17 percent of intracanalicular tumors grow. 30 percent of extrameatal tumors grow.
An important note!!! Despite the fact that tumors largely stopped growing, hearing continued to be affected.
In a study of 1,144 patients treated with just observation, hearing loss continued through 10 years. The greatest hearing loss is in the first few years of diagnosis. But...without treatment...60 percent of the patients remained in class I hearing (70 to 100 percent word recognition) through 5 years. 50 percent after 10 years.
So so much information given. Tumor size has a direct correlation to hearing saved. In order of importance/consideration:
Hearing status preop - If hearing is already affected greatly then smaller chance at preserving useable hearing.
Tumor Size - Major drop in in hearing salvage with increasing size above 1.5cm.
Tumor Location - Which vestibular nerve the growth is on, how far lateral/medial, and modiolar invasion.
Age, Health status, and NF2 factors finished the list.
If left untreated (via Chpra, Kondziolka, Niranjan, Lunsford, Flickinger)...
74 percent started with serviceable hearing, after 10 years, 44.5% had serviceable hearing. So similar to other studies.
Another study with tumor growth vs hearing (Sughrue Kane Kaur Barry Rutkowski Pitts Cheung Parsa)
Best predictor of hearing loss tumor growth >2.5mm/yr
Median time to deaf >2.5mm/yr = 7 years.
Median time to deaf <2.5mm/yr = 14.8 years.
Intracanalicular = 11.6 years.
0.1-1 cm into CPA = 10.3 years.
>1 cm into CPA = 9.3 years.
No different for NF2.
Examples were given for real cases. 22 yo woman with no health issues with mild unilateral hearing loss with tinnitus. 9 mm intracanalicular tumor. Recommendation is surgery soon to preserve hearing since risk to hearing will begin fairly soon (>1.5cm).
48 yo man 4 years slowly progressive hearing loss, tinnitus. 1.7cm tumor, poor hearing salvage potential. All options (surgery, radiation, observation) have similar value since hearing is not likely to be saved long term. This man chose cyberknife, 18 Gy in 3 sessions. 4 month post had grade II HB facial paresis. Hearing was down, tumor same size.
3rd example was 72 yo woman. Moderate hearing loss, progressive over 7 years. 2.8cm tumor, moderate hypertension, diabetes, appears elderly for her age, moderate brain atrophy with microangiopathy. Off balance, minimally worse with quick movement, moderate tinnitus. Recommendation was radiation. Observation risked brainstem with growth. Well, tumor grew or swelled to 3.5cm. Patient became unable to walk w/o assistance. Pt level of consciousness/cognitive function declined, loss of urinary control. Acute hydrocephalus. CSF shunt done. Just goes to show that not all cases are clear cut. They later debrided tumor to minimal along facial nerve. Walking and cognition returned to pre-morbid.
THEN...we got to watch them perform the surgery on 3 cadavers (just the heads) in 3-D on a big screen! There was no tumor, but they showed us all the approaches, and where the nerves are located, how they separate the nerves for tumor resection. All I can say is WOW! They showed us two blood vessels close to each other. One was minor and should be cauterized to prevent bleeding. The one right behind is major and should not be touched. If it is inadvertantly affected, risk of stroke! Amazing stuff!
Ernie
