Hi, Julie:
Welcome to our forum. Others have already addressed the issues of headaches and candidacy for radiation treatments, so I'll talk about radiation vs surgery. Of course, radiation is not invasive (except very minimally so if you have GammaKnife (GK), due to the 3 screws that are used to secure a metal crown to your head during the procedure). For medium-size tumors in particular, I believe the general consensus is that there is a significantly greater risk of facial paralysis or numbness following surgery compared to with radiation; radiation poses negligible risk -- about 1% chance -- in that regard. With surgery, you run additional risks of cerebrospinal fluid leakage (draining down the Eustachian tube on the operated side and out the nose), hydroencephalitis, chronic headaches (roughly a 10 to 15% chance with retrosigmoid -- or behind-the-ear -- surgical approach), and (relatively rarely) cognitive and behavioral changes (presumably caused by prolonged anesthesia or the prolonged retraction of the cerebellum with some surgical approaches). Radiation virtually poses none of these risks, although some people report headaches after treatment.
Radiation doesn't remove a tumor, however, so you're stuck with a dead tumor in your head. In roughly 25% of cases, the tumor may shrink significantly. But that takes time. And in the meantime, the tumor may first swell to a larger size, putting more pressure on cranial nerves and possibly the brainstem, which may cause an increase in symptoms (although they almost always disappear within several months). Many people report having no side effects or only moderate fatigue after radiation, while others report having severe fatigue, vertigo or disequilibrium, increased tinnitus and partial (or in some cases, severe or total) hearing loss. Usually, the symptoms you might get after radiation are limited to only those you had before treatment, only worsened. Also, it's important to realize that a tumor takes a couple years or more to die after being irradiated, during which time it is still doing its evil deeds.
If you find yourself leaning towards radiation, you should research GK and CK (CyberKnife) and traditional FSR (fractionated stereotactic radiation). They all differ in the homogeneity of radiation delivered, accuracy, and statistical results. My own bias is towards CK, as that's what I had. CK delivers the most homogeneous dose of radiation and offers a slightly better chance of hearing preservation compared to GK. GK and CK are the most accurate, thereby minimizing collateral damage of healthy tissues.
I hope that helps,
TW